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Men's Health Concerns
Beat hypertensionLower your blood pressure with simple lifestyle changes to protect yourself from this hidden health problem. According to research or other evidence, the following self-care steps may be helpful:
- Sidestep salt
- Avoid using too much table salt, limit salty fast foods, and read labels to find low-sodium foods in your grocery store
- Watch what you eat
- Choose a diet low in cholesterol and animal fat, and high in fruits, vegetables, whole grains, legumes, and low-fat milk products, with some nuts and seeds
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Boost heart health with supplemental garlic
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600 to 900 mg a day of a standardized garlic extract can improve heart and blood vessel health, and also has a mild blood pressurelowering effect
About hypertension
Approximately 90% of people with high blood pressure have essential or idiopathic hypertension, for which the cause is poorly understood. The terms hypertension and high blood pressure as used here refer only to this most common form and not to pregnancy-induced hypertension or hypertension clearly linked to a known cause, such as Cushings syndrome, pheochromocytoma, or kidney disease. Hypertension must always be evaluated by a healthcare professional. Extremely high blood pressure (malignant hypertension) or rapidly worsening hypertension (accelerated hypertension) almost always requires treatment with conventional medicine. People with mild to moderate high blood pressure should work with a doctor before attempting to use the information contained here, as blood pressure requires monitoring and in some cases the use of blood pressure-lowering drugs.
As with conventional drugs, the use of natural substances sometimes controls blood pressure if taken consistently but does not lead to a cure for high blood pressure. Thus, someone whose blood pressure is successfully reduced by weight loss, avoidance of salt, and increased intake of fruits and vegetables would need to maintain these changes permanently in order to retain control of blood pressure. Left untreated, hypertension significantly increases the risk of stroke and heart disease.
What are the symptoms?
Essential hypertension is usually without symptoms until complications develop. The symptoms of complications depend on the organs involved.
Dietary changes that may be helpful
Primitive societies exposed to very little salt suffer from little or no hypertension. Salt (sodium chloride) intake has also been definitively linked to hypertension in western societies. Reducing salt intake in the diet lowers blood pressure in most people. The more salt is restricted, the greater the blood pressure-lowering effect. Individual studies sometimes come to differing conclusions about the relationship between salt intake and blood pressure, in part because blood pressure-lowering effects of salt restriction vary from person to person, and small to moderate reductions in salt intake often have minimal effects on blood pressureparticularly in young people and in those who do not have hypertension. Nonetheless, dramatic reductions in salt intake are generally effective for many people with hypertension.
With the prevalence of salted processed and restaurant food, simply avoiding the salt shaker no longer leads to large decreases in salt intake for most people. Totally eliminating salt is more effective, but is quite difficult to achieve. Moreover, while an overview of the research found There is no evidence that sodium reduction presents any safety hazards, reports of short-term paradoxical increases in blood pressure in response to salt restriction have occasionally appeared. Therefore, people wishing to use salt reduction to lower their blood pressure should consult with a doctor.
Vegetarians have lower blood pressure than do people who eat meat. This occurs partly because fruits and vegetables contain potassiuma known blood pressure-lowering mineral. The best way to supplement potassium is with fruit, which contains more of the mineral than do potassium supplements. However, fruit contains so much potassium that people taking potassium-sparingdiuretics can consume too much potassium simply by eating several pieces of fruit per day. Therefore, people taking potassium-sparing diuretics should consult the prescribing doctor before increasing fruit intake. In the Dietary Approaches to Stop Hypertension (DASH) trial, increasing intake of fruits and vegetables (and therefore fiber) and reducing cholesterol and dairy fat led to large reductions in blood pressure (in medical terms, 11.4 systolic and 5.5 diastolic) in just eight weeks. Even though it did not employ a vegetarian diet itself, the outcome of the DASH trial supports the usefulness of vegetarian diets because diets employed by DASH researchers were related to what many vegetarians eat. The DASH trial also showed that blood pressure can be significantly reduced in hypertensive people (most dramatically in African Americans) with diet alone, without weight loss or even restriction of salt. Nonetheless, restricting salt while consuming the DASH diet has lowered blood pressure even more effectively than the use of the DASH diet alone.
Sugar has been reported to increase blood pressure in animals and humans in short-term trials. Though the real importance of this experimental effect remains unclear, some doctors recommend that people with high blood pressure cut back on their intake of sugar.
Right after consuming caffeine from coffee or tea, blood pressure increases briefly. In trials lasting almost two months on average, coffee drinking has led to small increases in blood pressure. The effects of long-term avoidance of caffeine (from coffee, tea, chocolate, cola drinks, and some medications) on blood pressure remain unclear. A few reports have even claimed that long-term coffee drinkers tend to have lower blood pressure than those who avoid coffee. Despite the lack of clarity in published research, many doctors tell people with high blood pressure to avoid consumption of caffeine.
Several double-blind trials have shown that adding 6.57 grams of fiber per day to the diet for several months leads to reductions in blood pressure. However, other trials have not found fiber helpful in reducing blood pressure. The reason for these discrepant findings is not clear.
Food allergy was reported to contribute to high blood pressure in a study of people who had migraine headaches. In that report, all 15 people who also had high blood pressure experienced a significant drop in blood pressure when put on a hypoallergenic diet. People who suffer migraine headaches and have hypertension should discuss the issue of allergy diagnosis and elimination with a doctor.
Reusing vegetable oils for frying, especially oils with high concentrations of unsaturated fatty acids (such as sunflower or safflower oil) has been associated with an increased risk of high blood pressure. Presumably, this increased risk is due to some of the degradation products (such as lipid peroxides or polymers) that result from the excessive heating of these oils. Frying with more stable oils, such as olive oil, is not associated with an increased risk of high blood pressure.
Exposure to lead and other heavy metals has been linked to high blood pressure in some, but not all, research. If other approaches to high blood pressure prove unsuccessful, it makes sense for people with hypertension to have their bodys burden of lead evaluated by a healthcare professional.
In a double-blind trial, supplementation with a tomat extract significantly lowered both systolic and diastolic blood pressure, compared with a placebo, in people with hypertension. The amount of extract used was 250 mg per day (providing 15 mg per day of lycopene plus other carotenoids) for eight weeks.
Lifestyle changes that may be helpful
Smoking is particularly injurious for people with hypertension. The combination of hypertension and smoking greatly increases the risk of heart diseaserelated sickness and death. All people with high blood pressure need to quit smoking.
Consumption of more than about three alcoholic beverages per day appears to increase blood pressure. Whether one or two drinks per day meaningfully increases blood pressure remains unclear.
Daily exercise can lower blood pressure significantly. A 12-week program of Chinese Tai Chi was reported to be almost as effective as aerobic exercise in lowering blood pressure. Progressive resistance exercise (e.g., weight lifting) also appears to help reduce blood pressure. At the same time, blood pressure has been known to increase significantly during the act of lifting heavy weights; for this reason, people with sharply elevated blood pressure, especially those with cardiovascular disease, should approach heavy strenuous resistance exercise with caution. In general, people over 40 years of age should consult with their doctors before starting any exercise regimen.
Most people with high blood pressure are overweight. Weight loss lowers blood pressure significantly in those who are both overweight and hypertensive. In fact, reducing body weight by as little as ten pounds can lead to a significant reduction in blood pressure. Weight loss appears to have a stronger blood pressure-lowering effect than dietary salt restriction.
Other therapies
Healthcare practitioners may also recommend lifestyle modifications, such as moderate weight reduction and a decrease in salt intake. Though essential hypertension has no cure, treatment can modify its course and reduce the risk of complications.
Vitamins that may be helpful
Both preliminary and double-blind trials have reported that supplementation with Coenzyme Q10 (CoQ10) leads to a significant decrease in blood pressure in people with hypertension. Much of this research has used 100 mg of CoQ10 per day for at least ten weeks.
EPA and DHA, the omega-3 fatty acids found in fish oil, lower blood pressure, according to an analysis of 31 trials. The effect was dependent on the amount of omega-3 oil used, with the best results occurring in trials using unsustainably high levels: 15 grams per daythe amount often found in 50 grams of fish oil. Although results with lower intakes were not as impressive, trials using over 3 grams per day of omega-3 (as typically found in ten 1,000 mg pills of fish oil) also reported significant reductions in blood pressure. One double-blind trial reported that DHA had greater effects on blood pressure than EPA or mixed fish oil supplements. DHA is now available as a supplement separate from EPA.
Potassium supplements in the amount of at least 2,400 mg per day lower blood pressure, according to an analysis of 33 trials. However, potassium supplements greater than 100 mg per tablet require a prescription, and the low-dose potassium supplements available without a prescription can irritate the stomach if taken in large amounts. Moreover, some people, such as those taking potassium-sparing diuretics, should not take potassium supplements. Therefore, the use of potassium supplements for lowering blood pressure should only be done under the care of a doctor.
Some, but not all, trials show that magnesium supplementstypically 350500 mg per daylower blood pressure. Magnesium appears to be particularly effective in people who are taking potassium-depleting diuretics. Potassium-depleting diuretics also deplete magnesium. Therefore, the drop in blood pressure resulting from magnesium supplementation in people taking these drugs may result from overcoming a mild magnesium deficiency.
Calcium supplementationtypically 8001,500 mg per daymay lower blood pressure. However, while an analysis of 42 trials reported that calcium supplementation led to an average drop in blood pressure that was statistically significant, the actual decrease was small (in medical terms, a drop of 1.4 systolic over 0.8 diastolic pressure). Results might have been improved had the analysis been limited to studies of people with hypertension, since calcium has almost no effect on the blood pressure of healthy people. In the analysis of 42 trials, effects were seen both with dietary calcium and with use of calcium supplements. A 12-week trial of 1,000 mg per day of calcium accompanied by blood pressure monitoring is a reasonable way to assess efficacy in a given person.
In a double-blind trial, women with low blood levels of vitamin D (measured as 25-hydroxyvitamin D3) were given a calcium supplement, plus either 800 IU of vitamin D per day or a placebo for eight weeks. Compared with the placebo, vitamin D significantly reduced systolic blood pressure by an average of 9.3%, but did not affect diastolic blood pressure.
In a double-blind study, supplementation with 2 mg of sustained-release melatonin each night for four weeks significantly reduced nighttime systolic blood pressure, compared with a placebo, in people with nocturnal hypertension. Normally, blood pressure declines at night. People with hypertension who do not have this nighttime blood pressure decline are at increased risk of developing and dying from heart disease. Melatonin supplementation may therefore be beneficial for this subgroup of people with hypertension.
In a double-blind study of postmenopausal women, supplementing with 10 grams of soy protein twice a day for six weeks significantly reduced diastolic blood pressure by an average of 5 mm Hg, compared with a diet not containing soy protein. In another study, men and women with mild to moderate hypertension consumed 500 ml (approximately 16 ounces) of soy milk or cow's milk twice a day for three months. After three months, the average systolic blood pressure had decreased by 18.4 mm Hg in the soy group, compared with 1.4 mm Hg in the cow's milk group. The reductions in diastolic blood pressure were 15.9 mm Hg with soy milk and 3.7 mm Hg with cow's milk. In another study of people with hypertension who were consuming a low-protein, low-fiber diet, supplementing with a combination of soy protein and psyllium (a fiber source) lowered systolic blood pressure by an average of 5.9 mm Hg. The blood pressure reduction with soy protein alone or with fiber alone was less pronounced than that with combination treatment. Other research has also shown a blood pressurelowering effect of soy protein.
Five double-blind trials have found that vitamin Csupplementation reduces blood pressure, but the reduction was statistically significant in only three of the five, and in most cases reductions were modest. Some doctors recommend that people with elevated blood pressure supplement with 1,000 mg vitamin C per day.
In a double-blind study of people with high blood pressure, 200 IU of vitamin E per day taken for 27 weeks was significantly more effective than a placebo at reducing both systolic and diastolic blood pressure. This study was done in Iran, and it is not clear whether the results would apply to individuals consuming a Western diet.
A deficiency of the amino acid taurine, is thought by some researchers to play an important role in elevating blood pressure in people with hypertension. Limited research has found that supplementation with taurine lowers blood pressure in animals and in people (at 6 grams per day), possibly by reducing levels of the hormone epinephrine (adrenaline).
The amino acid arginine is needed by the body to make nitric oxide, a substance that allows blood vessels to dilate, thus leading to reduced blood pressure. Intravenous administration of arginine has reduced blood pressure in humans in some reports. In one controlled trial, people not responding to conventional medication for their hypertension were found to respond to a combination of conventional medication and oral arginine (2 grams taken three times per day.)
Herbs that may be helpful
In a double-blind trial, people with mild hypertension took a tincture of Achillea wilhelmsii, an herb used in traditional Persian medicine. Participants in the trial used 1520 drops of the tincture twice daily for six months. At the end of the trial, participants experienced significant reductions in both systolic and diastolic blood pressure compared to those who took placebo. No adverse effects were reported.
Garlic has a mild blood pressure-lowering effect, according to an analysis of ten double-blind trials. All of these trials administered garlic for at least four weeks, typically using 600900 mg of garlic extract per day. Onionclosely related to garlicmay also have a mild blood pressure-lowering effect, according to preliminary research.
Two controlled clinical trials have shown that hibiscus can lower blood pressure. In one, people with high blood pressure who went off their medications were given either 2 teaspoons (5 to 6 grams) Hibiscus sabdariffa infused in 1 cup (250 ml) water or black tea three times per day.67 After 12 days the hibiscus group had significantly lower blood pressure than the black tea group. In another trial 10 grams of Hibiscus sabdariffa tea was compared to the drug captopril for four weeks in people with high blood pressure.68 Blood pressures fell an equal amount in both groups, suggesting this herbal tea may be as potent as some blood pressure medications.
European mistletoe (Viscum album) has reduced headaches and dizziness associated with high blood pressure, according to preliminary research. Mistletoe may be taken as 0.5 ml tincture three times per day. The blood pressure-lowering effect of mistletoe is small and may take weeks to become evident. Due to possible serious side effects, European mistletoe should only be taken under the careful supervision of a physician trained in its use.
Indian snakeroot (Rauwolfia serpentina) contains powerful alkaloids, including reserpine, that affect blood pressure and heart function. Indian snakeroot has been used traditionally to treat hypertension, especially when associated with stress and anxiety. Due to possible serious side effects, Indian snakeroot should only be taken under the careful supervision of a physician trained in its use.
In animal studies oleuropein, one of the constituents of olive leaf, has decreased blood pressure and dilated arteries surrounding the heart, when given by injection or intravenously. Olive leaf has been used traditionally to treat people with hypertension, but controlled human trials are needed before a blood pressure-lowering effect can be established.
A double-blind trial reported that reishi mushrooms significantly lowered blood pressure in humans. The trial used a concentrated extract of reishi (25:1) in the amount of 55 mg three times per day for four weeks. It is unclear from the clinical report how long it takes for the blood pressure-lowering effects of reishi to be measured.
Hawthorn leaf and flower extracts have been reported to have a mild blood pressurelowering effect in people with early stage congestive heart failure. In a double-blind study, supplementation with a hawthorn extract significantly decreased diastolic blood pressure in people with type 2 diabetes. The amount used was 1,200 mg per day of an extract standardized to 2.2% flavonoids corresponding to 6 per day of dried flowering tops.
Human trials investigating the use of Coleus forskohlii in blood pressure reduction have yet to be conducted. However, forskolin, the active ingredient in Coleus forskohlii, has lowered blood pressure in a small, preliminary trial with people suffering from cardiomyopathy. Extracts of coleus standardized to contain 1520% forskolin are available, but further trials are needed to determine effective levels for treating people with hypertension.
Most herbal reference books suggest that ginseng should not be used by people with hypertension. However, the results of a preliminary trial suggest that red ginseng root (Panax ginseng radix rubra) has either no effect on, or may actually slightly lower, blood pressure in hypertensive people. However, many herbalists continue to believe that people with hypertension should avoid Asian ginsen and American ginseng, and, while not a true ginseng, Siberian ginseng (eleuthero) as well.
Holistic approaches that may be helpful
Anxiety in men (but not women) has been linked to development of hypertension. Several research groups have also shown a relationship between job strain and high blood pressure in men. Some researchers have tied blood pressure specifically to suppressed aggression.
Although some kind of relationship between stress and high blood pressure appears to exist, the effects of treatment for stress remain controversial. An analysis of 26 trials reported that reductions in blood pressure caused by biofeedback or meditation were no greater than those seen with placebo. Though some stress management interventions have not been helpful in reducing blood pressure, those trials that have reported promising effects have used combinations of yoga, biofeedback, and/or meditation. Some doctors continue to recommend a variety of stress-reducing measures, sometimes tailoring them to the needs and preferences of the person seeking help.
Preliminary laboratory studies in animals and humans suggest that acupuncture may help regulate blood pressure. Most, but not all, preliminary trials also suggest that acupuncture may be an effective way to lower blood pressure. Whether blood pressure goes back up after acupuncture is discontinued remains an unsettled question.
Auricular (ear) acupressure has been reported to be an effective treatment for hypertension, though in one case the improvement was not significantly better than use of traditional herbal medicines.
Spinal manipulation may lower blood pressure (at least temporarily) in healthy people, according to most preliminary and controlled trials. However, some research suggests the effect is no better than the blood pressure-lowering effect of sham (fake) manipulation. In hypertensive people, temporary decreases in blood pressure have also been reported after spinal manipulation. However, most, but not all, trials suggest that manipulation produces only short-term decreases in blood pressure in hypertensive people.
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Vitamin Shoppe has all your supplemental needs.
         
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Cholesterol
Take control of your cholesterol to lower your heart disease risk. According to research or other evidence, the following self-care steps may be helpful:
- Cut the bad fats
- Foods that contain saturated fat, hydrogenated fat, and cholesterol (such as animal products, fried foods, and baked snacks) can raise cholesterol
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full high cholesterol article for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and lifestyle changes that may be helpful.
About high cholesterol
Although it is by no means the only major risk factor, elevated serum (blood) cholesterol is clearly associated with a high risk of heart disease.
Most doctors suggest cholesterol levels should stay under 200 mg/dl. As levels fall below 200, the risk of heart disease continues to decline. Many doctors consider cholesterol levels of no more than 180 to be optimal. A low cholesterol level, however, is not a guarantee of good heart health, as some people with low levels do suffer heart attacks.
Medical laboratories now subdivide total cholesterol measurement into several components, including LDL (bad) cholesterol, which is directly linked to heart disease, and HDL (good) cholesterol, which is protective. The relative amount of HDL to LDL is more important than total cholesterol. For example, it is possible for someone with very high HDL to be at relatively low risk for heart disease even with total cholesterol above 200. Evaluation of changes in cholesterol requires consultation with a healthcare professional and should include measurement of total serum cholesterol, as well as HDL and LDL cholesterol.
The following discussion is limited to information about lowering serum cholesterol levels or increasing HDL cholesterol using natural approaches. Because high cholesterol is linked to atherosclerosis and heart disease, people concerned about heart disease should also learn more about atherosclerosis.
What are the symptoms?
This condition does not produce symptoms. Therefore, it is prudent to visit a health professional on a regular basis to have cholesterol levels measured.
Dietary changes that may be helpful
Eating animal foods containing saturated fat is linked to high cholesterol levels and heart disease. Significant amounts of animal-based saturated fat are found in beef, pork, veal, poultry (particularly in poultry skins and dark meat), cheese, butter, ice cream, and all other forms of dairy products not labeled fat free. Avoiding consumption of these foods reduces cholesterol and has been reported to reverse even existing heart disease.
Unlike other dairy foods, skimmed milk, nonfat yogurt, and nonfat cheese are essentially fat-free. Dairy products labeled low fat are not particularly low in fat. A full 25% of calories in 2% milk come from fat. (The 2% refers to the fraction of volume filled by fat, not the more important percentage of calories coming from fat.)
In addition to large amounts of saturated fat from animal-based foods, Americans eat small amounts of saturated fat from coconut and palm oils. Palm oil has been reported to elevate cholesterol. Research regarding coconut oil is mixed, with some trials finding no link to heart disease, while other research reports that coconut oil elevates cholesterol levels.
Despite the links between saturated fat intake and serum cholesterol levels, not every person responds to appropriate dietary changes with a drop in cholesterol. A subgroup of people with elevated cholesterol who have what researchers call large LDL particles has been reported to have no response even to dramatic reductions in dietary fat. (LDL is the bad cholesterol most associated with an increased risk of heart disease.) This phenomenon is not understood. People who significantly reduce intake of animal fats for several months but do not see significant a reduction in cholesterol levels should discuss other approaches to lowering cholesterol with a doctor.
Yogurt, acidophilus milk, and kefir are fermented milk products that have been reported to lower cholesterol in most, but not all, double-blind and other controlled research. Until more is known, it makes sense for people with elevated cholesterol who consume these foods, to select nonfat varieties.
Eating fish has been reported to increase HDL cholesterol and is linked to a reduced risk of heart disease in most, but not all, studies. Fish contains very little saturated fat, and fish oil contains EPA and DHA, omega-3 fatty acids that appear to protect against heart disease.
Vegetarians have lower cholesterol and less heart disease than meat eaters, in part because they avoid animal fat. Vegans (people who eat no meat, dairy, or eggs) have the lowest cholesterol levels, and switching from a standard diet to a vegan diet, along with other lifestyle changes, has been reported to reverse heart disease in controlled research.
Dietary cholesterol
Most dietary cholesterol comes from egg yolks. Eating eggs has increased serum cholesterol in most studies. However, eating eggs does not increase serum cholesterol as much as eating foods high in saturated fat, and eating eggs may not increase serum cholesterol at all if the overall diet is low in fat.
Egg consumption does not appear to be totally safe, however, even for people consuming a low-fat diet. When cholesterol from eggs is cooked or exposed to air, it oxidizes. Oxidized cholesterol is linked to increased risk of heart disease. Eating eggs also makes LDL cholesterol more susceptible to damage, a change linked to heart disease.
Whether or not egg eaters are more likely to die from heart disease is a matter of controversy. In one preliminary study, egg eaters had a higher death rate from heart disease, even when serum cholesterol levels were not elevated. However, another preliminary study found no evidence of an overall significant association between egg consumption, and risk of heart disease or stroke, except in people with diabetes. Until more is known, limiting egg consumption may be a good idea, particularly for people with existing heart disease or diabetes.
While coconut oil is high in saturated fat, some evidence suggests it does not cause unhealthy changes in blood cholesterol levels compared with other saturated fats. In a controlled study of people with high cholesterol, coconut oil resulted in higher total and LDL cholesterol levels compared with safflower oil (a polyunsaturated oil), but lower levels compared with butter, while HDL levels were similar for all three diets. Another controlled study compared coconut oil with canola oil, and found that coconut oil raised total and LDL cholesterol in people with high cholesterol who were not taking cholesterol-lowering drugs, but did not affect these levels in people who were taking these drugs. HDL levels were not reported in this study.
Fiber
Soluble fiber from beans, oats, psyllium seed, glucomannan, and fruit pectin has lowered cholesterol levels in most trials. Doctors often recommend that people with elevated cholesterol eat more of these high-soluble fiber foods. However, even grain fiber (which contains insoluble fiber and does not lower cholesterol) has been linked to protection against heart disease, though the reason for the protection remains unclear. It makes sense for people wishing to lower their cholesterol levels and reduce the risk of heart disease to consume more fiber of all types. Some trials have used 20 grams of additional fiber per day for several months to successfully lower cholesterol. Psyllium has also been found to enhance the effect of the cholesterol-lowering drug simvastatin.
Oat bran is rich in a soluble fiber called beta-glucan. In 1997, the U.S. Food and Drug Administration passed a unique ruling that allowed oat bran to be registered as the first cholesterol-reducing food at an amount providing 3 grams of beta-glucan per day, although some evidence suggests this level may not be high enough to make a significant difference.4Several double-blind and other controlled trials have shown that oat bran and oat milk supplementation may significantly lower cholesterol levels in people with elevated cholesterol, but only weakly lowers them in people with healthy cholesterol levels.
Flaxseed, another good source of soluble fiber, has been reported to lower total and LDL cholesterol in preliminary studies. A double-blind trial found that while both flaxseed and sunflower seed lowered total cholesterol, only flaxseed significantly lowered LDL. Amounts of flaxseed used in these trials typically range from 3050 grams per day. A controlled trial found that partially defatted flaxseed, containing 20 grams of fiber per day, significantly lowered LDL cholesterol, suggesting that at least one of the cholesterol-lowering components in flaxseed is likely to be the fiber in this product, as opposed to the oil removed from it. Controlled trials of flaxseed oil alone have shown inconsistent effects on blood
cholesterol.
Alpha-linolenic acid
Doctors and researchers are interested in alpha-linolenic acid (ALA)the special omega-3 fatty acid found in large amounts in flaxseeds and flaxseed oil. ALA is a precursor to EPA, a fatty acid from fish oil that is believed to protect against heart disease. To a limited extent, ALA converts to EPA within the body. However, unlike EPA, ALA does not lower triglyceride levels (a risk factor for heart disease). Preliminary research on the effects of ALA from flaxseed has produced conflicting results.
In 1994, researchers conducted a study in people with a history of heart disease, using what they called the "Mediterranean" diet. The diet was significantly different from what people from Mediterranean countries actually eat, in that it contained little olive oil. Instead, the diet included a special margarine high in ALA. Those people assigned to the "Mediterranean" diet had a remarkable 70% reduced risk of dying from heart disease compared with the control group during the first 27 months. Similar results were also confirmed after almost four years. Although cholesterol levels fell only modestly in the "Mediterranean" diet group, the positive results suggest that people with elevated cholesterol attempting to reduce the risk of heart disease should consider such a diet. The diet was high in beans and peas, fish, fruit, vegetables, bread, and cereals; and low in meat, dairy fat, and eggs. Although the authors believe that the high ALA content of the diet was partially responsible for the surprising outcome, other aspects of the diet may have been partly or even totally responsible for decreased death rates. Therefore, the success of the "Mediterranean" diet does not prove that ALA protects against heart disease.
Soy
Tofu, tempeh, miso, and some protein powders in health food stores, are derived from soybeans. In 1995, an analysis of many trials proved that soy reduces both total and LDL cholesterol.6 Since then, other double-blind and other controlled trials have confirmed these findings. Trials showing statistically significant reductions in cholesterol have generally used more than 30 grams per day of soy protein. However, if soy replaces animal protein in the diet, as little as 20 grams per day has been shown to significantly reduce both total and LDL cholesterol. Isoflavones found in soy beans appear to be key cholesterol-lowering ingredients of the bean, but animal research suggests other components of soy are also important.
Sugar
Eating sugar has been reported to reduce protective HDL cholestero and increases other risk factors linked to heart disease. However, higher sugar intake has been associated with only slightly higher risks of heart disease in most reports. Although the exact relationship between sugar and heart disease remains somewhat unclear, many doctors recommend that people with high cholesterol reduce their sugar intake.
Coffee
Drinking boiled or French press coffee increases cholesterol levels. Modern paper coffee filters trap the offending chemicals and keep them from entering the cup. Therefore, drinking paper-filtered coffee does not increase cholesterol levels. Espresso coffee has amounts of the offending chemicals midway between those of other unfiltered coffees and paper-filtered coffee, but there is little research investigating the effect of espresso on cholesterol levels, and studies to date have produced conflicting results. The effects of decaffeinated coffee on cholesterol levels remain in debate.
Alcohol
Moderate drinking (one to two drinks per day) increases protective HDL cholesterol. This effect happens equally with different kinds of alcohol-containing beverages. Alcohol also acts as a blood thinner, an effect that should lower heart disease. However, alcohol consumption may cause liver disease (e.g., cirrhosis), cancer, high blood pressure, alcoholism, and, at high intake, an increased risk of heart disease. As a result, some doctors never recommend alcohol, even for people with high cholesterol. Nevertheless, those who have one to two drinks per day appear to live longer and are clearly less likely to have heart disease. Therefore, some people at very high risk of heart diseasethose who are not alcoholics, who have healthy livers and normal blood pressure, and who are not at high risk for cancer, particularly breast cancerare likely to receive more benefit than harm, from light drinking.
Olive oil
Olive oil lowers LDL cholesterol, especially when the olive oil replaces saturated fat in the diet. People from countries that use significant amounts of olive oil appear to be at low risk for heart disease. A double-blind trial showed that a diet high in monounsaturated fatty acids from olive oil, lowers cardiovascular disease risk by 25%, as compared with a 12% decrease from a low-fat (25% fat) diet. The trial also found that low-fat diets decrease HDL cholesterol by 4%, which is undesirable, since HDL cholesterol is protective against heart disease. Diets high in monounsaturated fatty acids from olive oil do not adversely affect HDL levels. Although olive oil is clearly safe for people with elevated cholesterol, it is, like any fat or oil, high in calories, so people who are overweight should limit its use.
Trans fatty acids and margarine
Trans fatty acids (TFAs) are found in many processed foods containing partially hydrogenated oils. The highest levels occur in margarine. Margarine consumption is linked to increased risk of unfavorable changes in cholesterol levels and heart disease. Margarine and other processed foods containing partially hydrogenated oils should be avoided.
However, special therapeutic margarines are now available that contain substances, called phytostanols, that block the absorption of cholesterol. The FDA has approved some of these margarines as legitimate therapeutic agents for lowering blood cholesterol levels. The best-known of these products is Benecol. The cholesterol-lowering effect of these margarines has been demonstrated in numerous double-blind and other controlled trials.
Garlic
Garlic is available as a food, as a spice in powder form, and as a supplement. Eating garlic has helped to lower cholesterol in some research, though several double-blind trials have not found garlic supplements to be thusly effective. Although some of the negative reports have been criticized, the relationship between garlic and cholesterol lowering remains unproven. However, garlic is known to act as a blood thinner111 and may reduce other risk factors for heart disease. For these reasons, some doctors recommend eating garlic as food, taking 900 mg of garlic powder from capsules, or using a tincture of 2 to 4 ml, taken three times daily.
Nuts
Preliminary research consistently shows that people who eat nuts frequently have a dramatically reduced risk of heart disease. This apparent beneficial effect is at least partially explained by preliminary and controlled research demonstrating that nut consumption lowers cholesterol levels. Of nuts commonly consumed, almonds and walnuts may be most effective at lowering cholesterol. Macadamia nuts have been less beneficial in most studies, although one controlled trial found a cholesterol-lowering effect from macadamia nuts. Hazelnuts and pistachio nuts have also been reported to help lower cholesterol.
Nuts contain many factors that could be responsible for protection against heart disease, including fiber, vitamin E, alpha-linolenic acid (found primarily in walnuts), oleic acid, magnesium, potassium, and arginine. Therefore, exactly how nuts lower cholesterol or lower the risk of heart disease remains somewhat unclear. Some doctors even believe that nuts may not be directly protective; rather, people busy eating nuts will not simultaneously be eating eggs, dairy, or trans fatty acids from margarine and processed food, the avoidance of which would reduce cholesterol levels and the risk of heart disease. Nonetheless, the remarkable consistency of research outcomes strongly suggests that nuts do help protect against heart disease. Although nuts are loaded with calories, a preliminary trial surprisingly reported that adding hundreds of calories per day from nuts for six months did not increase body weight in humans an outcome supported by other reports. Even when increasing nut consumption has led to weight gain, the amount of added weight has been remarkably less than would be expected, given the number of calories added to the diet. Given the number of calories per ounce of nuts, scientists do not understand why moderate nut consumption apparently has so little effect on body weight.
Number and size of meals
When people eat a number of small meals, serum cholesterol levels fall compared with the effect of eating the same food in three big meals. People with elevated cholesterol levels should probably avoid very large meals and eat more frequent, smaller meals.
Lifestyle changes that may be helpful
Exercise increases protective HDL cholesterol, an effect that occurs even from walking. Total and LDL cholesterol are typically lowered by exercise, especially when weight-loss also occurs. Exercisers have a relatively low risk of heart disease. However, people over 40 years of age, or who have heart disease, should talk with their doctor before starting an exercise program; overdoing it may actually trigger heart attacks.
Obesity increases the risk of heart disease, in part because weight gain lowers HDL cholesterol. Weight loss reduces the bodys ability to make cholesterol, increases HDL levels, and reduces triglycerides (another risk factor for heart disease). Weight loss also leads to a decrease in blood pressure.
Smoking is linked to a lowered level of HDL cholesterol and is also known to cause heart disease. Quitting smoking reduces the risk of having a heart attack.
The combination of feelings of hostility, stress, and time urgency is called type A behavior. Men, but not women, with these traits are at high risk for heart disease in most, but not all, studies. Stress or type A behavior may elevate cholesterol in men. Reducing stress and feelings of hostility has reduced the risk of heart disease.
Other therapies
People with high cholesterol are commonly advised to reduce their consumption of dietary cholesterol and saturated fats.
Vitamins that may be helpful
Glucomannan is a water-soluble dietary fiber that is derived from konjac root. Controlled and double-blind trials have shown that supplementation with glucomannan significantly reduced total blood cholesterol, LDL cholesterol, and triglycerides, and in some cases raised HDL cholesterol. Effective amounts of glucomannan for lowering blood cholesterol have been 4 to 13 grams per day.
Test tube and animal studies indicate that policosanol is capable of inhibiting cholesterol production by the liver. Extensive preliminary and double-blind research in Cuba and other countries in Latin America has demonstrated that taking 10 to 20 mg per day of policosanol extracted from sugar cane results in significant changes in blood cholesterol levels, including total cholesterol (17 to 21% lower on average), LDL cholesterol (21 to 29% lower), and HDL cholesterol (7 to 29% higher). However, virtually all of this research was conducted by a single research group from Cuba. Follow-up double-blind studies performed in the United States, Canada, and Germany found that sugar cane-derived policosanol in amounts of 10 to 80 mg per day taken for 12 weeks had no effect on serum cholesterol levels in people with initially high cholesterol levels. Until additional independent studies are performed, the effect of policosanol on serum cholesterol levels must be considered uncertain.
The combined results of nine double-blind trials indicate that supplementation with HMB (beta-hydroxy-beta-methylbutyrate effectively lowers total and LDL cholesterol. All trials used 3 grams per day, taken for three to eight weeks.
Vitamin C appears to protect LDL cholesterol from damage. In some clinical trials, cholesterol levels have fallen when people with elevated cholesterol supplement with vitamin C. Some studies report that decreases in total cholesterol occur specifically in LDL cholesterol. Doctors sometimes recommend 1 gram per day of vitamin C. A review of the disparate research concerning vitamin C and heart disease, however, has suggested that most protection against heart disease from vitamin C, is likely to occur with as little as 100 mg per day.
Pantethine, a byproduct of vitamin B5 (pantothenic acid), may help reduce the amount of cholesterol made by the body. Several preliminary and two controlled trials have found that pantethine (300 mg taken two to four times per day) significantly lowers serum cholesterol levels and may also increase HDL. However, one double-blind trial in people whose high blood cholesterol did not change with diet and drug therapy, found that pantethine was also not effective. Common pantothenic acid has not been reported to have any effect on high blood cholesterol.
Chromium supplementation has reduced total cholesterol, LDL cholesterol and increased HDL cholesterol in double-blind and other controlled trials, although other trials have not found these effects. One double-blind trial found that high amounts of chromium (500 mcg per day) in combination with daily exercise was highly effective, producing nearly a 20% decrease in total cholesterol levels in just 13 weeks.
Brewers yeast, which contains readily absorbable and biologically active chromium, has also lowered serum cholesterol. People with higher blood levels of chromium appear to be at lower risk for heart disease. A reasonable and safe intake of supplemental chromium is 200 mcg per day. People wishing to use brewers yeast as a source of chromium should look for products specifically labeled "from the brewing process" or "brewers yeast," since most yeast found in health food stores is not brewers yeast, and does not contain chromium. Optimally, true brewers yeast contains up to 60 mcg of chromium per tablespoon, and a reasonable intake is 2 tablespoons per day.
High amounts (several grams per day) of niacin, a form of vitamin B3, lower cholesterol, an effect recognized in the approval of niacin as a prescription medication for high cholesterol. The other common form of vitamin B3niacinamidedoes not affect cholesterol levels. Some niacin preparations have raised HDL cholesterol better than certain prescription drugs. Some cardiologists prescribe 3 grams of niacin per day or even higher amounts for people with high cholesterol levels. At such intakes, acute symptoms (flushing, headache, stomachache) and chronic symptoms (liver damage, diabetes, gastritis, eye damage, possibly gout) of toxicity may be severe. Many people are not able to continue taking these levels of niacin due to discomfort or danger to their health. Therefore, high intakes of niacin must only be taken under the supervision of a doctor.
Symptoms caused by niacin supplements, such as flushing, have been reduced with sustained-release (also called "time-release") niacin products. However, sustained-release forms of niacin have caused significant liver toxicity and, though rarely, liver failure One partial time-release (intermediate-release) niacin product has lowered LDL cholesterol and raised HDL cholesterol without flushing, and it also has acted without the liver function abnormalities typically associated with sustained-release niacin formulations. However, this form of niacin is available by prescription only.
In an attempt to avoid the side effects of niacin, alternative health practitioners increasingly use inositol hexaniacinate, recommending 500 to 1,000 mg, taken three times per day, instead of niacin. This special form of niacin has been reported to lower serum cholesterol but so far has not been found to cause significant toxicity.209 Unfortunately, compared with niacin, far fewer investigations have studied the possible positive or negative effects of inositol hexaniacinate. As a result, people using inositol hexaniacinate should not take it without the supervision of a doctor, who will evaluate whether it is helpful (by measuring cholesterol levels) and will make sure that toxicity is not occurring (by measuring liver enzymes, uric acid and glucose levels, and by taking medical history and doing physical examinations).
Soy supplementation has been shown to lower cholesterol in humans. Soy is available in foods such as tofu, miso, and tempeh and as a supplemental protein powder. Soy contains isoflavones, naturally occurring plant components that are believed to be soys main cholesterol-lowering ingredients. A controlled trial showed that soy preparations containing high amounts of isoflavones effectively lowered total cholesterol and LDL ("bad") cholesterol, whereas low-isoflavone preparations (less than 27 mg per day) did not. However, supplementation with either soy or non-soy isoflavones (from red clover) in pill form failed to reduce cholesterol levels in a group of healthy volunteers, suggesting that isoflavone may not be responsible for the cholesterol-lowering effects of soy. Further trials of isoflavone supplements in people with elevated cholesterol, are needed to resolve these conflicting results. In a study of people with high cholesterol levels, a soy preparation that contained soy protein, soy fiber, and soy phospholipids lowered cholesterol levels more effectively than isolated soy protein.
Soy contains phytosterols. One such molecule, beta-sitosterol, is available as a supplement. Beta-sitosterol alone, and in combination with similar plant sterols, has been shown to reduce blood levels of cholesterol in preliminary and controlled trials. This effect may occur because beta-sitosterol blocks absorption of cholesterol. In studying the effects of 0.8, 1.6, and 3.2 grams of plant sterols per day, one double-blind trial found that higher intake of sterols tended to result in greater reduction in cholesterol, though the differences between the effects of these three amounts were not statistically significant.
A synthetic molecule related to beta-sitosterol, sitostanol, is available in a special margarine and has also been shown to lower cholesterol levels. In one controlled trial, supplementation with 1.7 grams per day of a plant-sterol product containing mostly sitostanol, combined with dietary changes, led to a dramatic 24% drop in LDL ("bad") cholesterol compared with only a 9% decrease in the diet-only part of the trial. Other controlled and double-blind trials have confirmed these results. A review of double-blind trials on sitostanol found that a reduction in the risk of heart disease of about 25% may be expected from use of sitostanol-containing spreads, a larger clinical effect than that produced by people reducing their saturated fat intake. Supplementation with sitostanol in the amount of 1.8 grams per day for six weeks has also been shown to enhance the cholesterol-lowering effect of statin drugs.
Tocotrienols, a group of food-derived compounds that resemble vitamin E, may lower blood levels of cholesterol, but evidence is conflicting. Although tocotrienols inhibited cholesterol synthesis in test-tube studies, human trials have produced contradictory results. Two double-blind trials found that 200 mg per day of either gamma-tocotrienol or total tocotrienols were more effective than placebo, reducing cholesterol levels by 1315%. However, in another double-blind trial, 200 mg of tocotrienols per day failed to lower cholesterol levels, and a fourth double-blind trial found 140 mg of tocotrienols and 80 mg of vitamin E (d-alpha-tocopherol) daily resulted in no changes in total cholesterol, LDL cholesterol, or HDL cholesterol levels.
In a double-blind study of people with elevated blood levels of cholesterol or triglycerides, supplementation with krill oil from Antarctic krill (a zooplankton crustacean) for three months decreased levels of total cholesterol, LDL cholesterol, and triglycerides, and increased HDL-cholesterol levels. Krill oil was significantly more effective than both regular fish oil and a placebo.
Activated charcoal has the ability to adsorb (attach to) cholesterol and bile acids present in the intestine, preventing their absorption. Reducing the absorption of bile acids results in increased cholesterol breakdown by the liver. In controlled studies of people with high cholesterol, activated charcoal reduced total- and LDL-cholesterol levels, when given in amounts from 4 to 32 grams per day. Larger amounts were more effective: reductions in total and LDL cholesterol were 23% and 29%, respectively, with 16 grams daily, and 29% and 41% with 32 grams daily.238 Similar results were reported in other controlled and preliminary studies using 16 to 24 grams per day, but one small double-blind trial found no effect of either 15 or 30 grams per day in patients with high cholesterol.
Deficiency of the trace mineral, copper, has been linked to high blood cholesterol. In a controlled trial, daily supplementation with 3 to 4 mg of copper for eight weeks decreased blood levels of total cholesterol and LDL cholesterol, in a group of people over 50 years of age.
Beta-glucan is a type of soluble fiber molecule derived from the cell wall of bakers yeast, oats and barley, and many medicinal mushrooms, such as maitake. Beta-glucan is the key factor for the cholesterol-lowering effect of oat bran As with other soluble-fiber components, the binding of cholesterol (and bile acids) by beta-glucan and the resulting elimination of these substances in the feces is very helpful for reducing blood cholesterol. Results from a number of double-blind trials with either oat- or yeast-derived beta-glucan indicate typical reductions, after at least four weeks of use, of approximately 10% for total cholesterol and 8% for LDL ("bad") cholesterol, with elevations in HDL ("good") cholesterol ranging from zero to 16%.For lowering cholesterol levels, the amount of beta-glucan used has ranged from 2,900 to 15,000 mg per day.
Some preliminary and double-blind trials have shown that supplemental calcium reduces cholesterol levels. Possibly the calcium is binding with and preventing the absorption of dietary fat. However, other research has found no substantial or statistically significant effects of calcium supplementation on total cholesterol or HDL ("good") cholesterol. Reasonable supplemental levels are 800 to 1,000 mg per day.
In one double-blind trial, vitamin E increased protective HDL cholesterol, but several other trials, found no effect of vitamin E. However, vitamin E is known to protect LDL cholesterol from damage. Most cardiologists believe that only damaged LDL increases the risk of heart disease. Studies of the ability of vitamin E supplements to prevent heart disease have produced conflicting results, but many doctors continue to recommend that everyone supplement 400 IU of vitamin E per day to lessen the risk of having a heart attack.
L-carnitine is needed by heart muscle to utilize fat for energy. Some, but not all, preliminary trials report that carnitine reduces serum cholesterol. HDL cholesterol has also increased in response to carnitine supplementation. People have been reported in controlled research to stand a greater chance of surviving a heart attack if they are given L-carnitine supplements. Most trials have used 1 to 4 grams of carnitine per day.
Magnesium is needed by the heart to function properly. Although the mechanism is unclear, magnesium supplements (430 mg per day) lowered cholesterol in a preliminary trial. Another preliminary study reported that magnesium deficiency is associated with a low HDL cholesterol level. Intravenous magnesium has reduced death following heart attacks in some, but not all, clinical trials. Though these outcomes would suggest that people with high cholesterol levels should take magnesium supplements, an isolated double-blind trial reported that people with a history of heart disease assigned to magnesium supplementation experienced an increased number of heart attacks. More information is necessary before the scientific community can clearly evaluate the role magnesium should play for people with elevated cholesterol.
Chondroitin sulfate has lowered serum cholesterol levels in preliminary trials. Years ago, this supplement dramatically reduced the risk of heart attacks in a controlled, six-year follow-up of people with heart disease. The few doctors aware of these older clinical trials sometimes tell people with a history of heart disease or elevated cholesterol levels, to take approximately 500 mg of chondroitin sulfate three times per day.
Although lecithin has been reported to increase HDL cholesterol and lower LDL cholesterol, a review of the research found that the positive effect of lecithin was likely due to the polyunsaturated fat content of the lecithin. If this is so, it would make more sense to use inexpensive vegetable oil, rather than take lecithin supplements. However, an animal study found a cholesterol-lowering effect of lecithin independent of its polyunsaturate content. A double-blind trial found that 20 grams of soy lecithin per day for four weeks had no significant effect on total cholesterol, LDL cholesterol, HDL cholesterol, or triglycerides. Whether taking lecithin supplements is a useful way to lower cholesterol in people with elevated cholesterol levels remains unclear.
The fiber-like supplement chitosan appears to reduce the absorption of bile acids or cholesterol; either of these effects may cause a lowering of blood cholesterol. This effect has been repeatedly demonstrated in animals, and a preliminary human study showed that 3 to 6 grams per day of chitosan taken for two weeks resulted in a 6% drop in cholesterol and a 10% increase in HDL ("good") cholesterol. Another preliminary trial showed a 43% lowering of total cholesterol in people being treated for kidney failure with dialysis who took 4 grams per day of chitosan for 12 weeks. These people also appeared to have improved kidney function and less severe anemia after chitosan treatment. In a double-blind trial, however, administration of 2.4 grams of chitosan per day for three months to people with high cholesterol had no effect on their cholesterol levels.
Chitosan in large amounts, given with vitamin C, has been shown to reduce dietary fat absorption in animals fed a high-fat diet. However, the absorption of minerals and fat-soluble vitamins was also reduced by feeding animals large amounts of chitosan. In studies in humans, chitosan did not reduce the absorption of dietary fat.
Royal jelly has prevented the cholesterol-elevating effect of nicotine and has lowered serum cholesterol in animal studies. Preliminary human trials have also found that royal jelly may lower cholesterol levels. An analysis of cholesterol-lowering trials shows that 50 to 100 mg per day is the typical amount used in such research.
A double-blind trial found that 20 grams per day of creatine taken for five days, followed by ten grams per day for 51 days, significantly lowered serum total cholesterol and triglycerides, but did not change either LDL or HDL cholesterol, in both men and women. However, another double-blind trial found no change in any of these blood levels in trained athletes using creatine during a 12-week strength training program.301 Creatine supplementation in this negative trial was loweronly 5 grams per day were taken for the last 11 weeks of the study.
Octacosanol, a substance found in wheat germ oil, is sometimes available as a supplement. Small amounts (5 to 20 mg per day) of policosanol, an experimental supplement from Cuba consisting primarily of octacosanol, has led to large reductions in LDL cholesterol and/or increases in HDL. Octacosanol may lower cholesterol by inhibiting the livers production of cholesterol.
Homocysteine, a substance linked to heart disease risk, may increase the rate at which LDL cholesterol is damaged. While vitamin B6, vitamin B12, and folic acid lower homocysteine, a recent trial found no effect of supplements of these vitamins on protecting LDL cholesterol, even though homocysteine was lowered.
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful
Researchers have determined that one of the ingredients in red yeast rice, called monacolin K, inhibits the production of cholesterol by stopping the action of the key enzyme in the liver (i.e., HMG-CoA reductase) that is responsible for manufacturing cholesterol. The drug lovastatin (Mevacor.) acts in a fashion similar to this red-yeast-rice ingredient. However, the amount per volume of monacolin K in red yeast rice is small (0.2% per 5 mg) when compared to the 20 to 40 mg of lovastatin available as a prescription drug.
The red yeast rice used in various studies was a proprietary product called Cholestin., which contains ten different monacolins.
Note: Cholestin has been banned in the United States, as a result of a lawsuit alleging patent infringement.
Other red yeast rice products currently on the market differ from Cholestin in their chemical makeup. None contain the full complement of ten monacolin compounds that are present in Cholestin, and some contain a potentially toxic fermentation product called citrinin. Despite these concerns, other red yeast rice products are being widely used and anecdotal reports suggest that they have a similar safety and efficacy profile as that of Cholestin.
Use of psyllium has been extensively studied as a way to reduce cholesterol levels. An analysis of all double-blind trials in 1997 concluded that a daily amount of 10 grams psyllium lowered cholesterol levels by 5% and LDL cholesterol by 9%. Since then, a large controlled trial found that use of 5.1 grams of psyllium two times per day significantly reduced serum cholesterol as well as LDL-cholesterol. Generally, 5 to 10 grams of psyllium are added to the diet per day to lower cholesterol levels. The combination of psyllium and oat bran may also be effective at lowering LDL cholesterol.
Guggul, a mixture of substances taken from a plant, is an approved treatment for elevated cholesterol in India and has been a mainstay of the Ayurvedic approach to preventing atherosclerosis. One double-blind trial studying the effects of guggul reported that serum cholesterol dropped by 17.5%. In another double-blind trial comparing guggul to the drug clofibrate, the average fall in serum cholesterol was slightly greater in the guggul group; moreover, HDL cholesterol rose in 60% of people responding to guggul, while clofibrate did not elevate HDL. A third double-blind trial found significant changes in total and LDL cholesterol levels, but not in HDL. However, in another double-blind trial, supplementation with guggul for eight weeks had no effect on total serum cholesterol, but significantly increased LDL-cholesterol levels, compared with a placebo. Daily intakes of guggul are based on the amount of guggulsterones in the extract. The recommended amount of guggulsterones is 25 mg taken three times per day. Most extracts contain 5 to 10% guggulsterones, and doctors familiar with their use usually recommend taking guggul for at least 12 weeks before evaluating its effect.
In a double-blind trial, people with moderately high cholesterol took a tincture of Achillea wilhelmsii, an herb used in traditional Persian medicine. Participants in the trial used 15 to 20 drops of the tincture twice daily for six months. At the end of the trial, participants experienced significant reductions in total cholesterol, LDL cholesterol and triglycerides, as well as an increase in HDL cholesterol compared to those who took placebo. No adverse effects were reported.
Reports on many double-blind garlic trials performed through 1998 suggested that cholesterol was lowered by an average of 9 to 12% and triglycerides by 8 to 27% over a one-to-four month period. Most of these trials used 600 to 900 mg per day of garlic supplements. More recently, however, several double-blind trials have found garlic to have minimal success in lowering cholesterol and triglycerides. One negative trial has been criticized for using a steam-distilled garlic "oil" that has no track record for this purpose, while the others used the same standardized garlic products as the previous positive trials. Based on these findings, the use of garlic should not be considered a primary approach to lowering high cholesterol and triglycerides.
Part of the confusion may result from differing effects from dissimilar garlic products. In most but not all trials, aged garlic extracts and garlic oil (both containing no allicin) have not lowered cholesterol levels in humans. Therefore, neither of these supplements can be recommended at this time for cholesterol lowering. Odor-controlled, enteric-coated tablets standardized for allicin content are available and, in some trials, appear more promising. Doctors typically recommend 900 mg per day (providing 5,000 to 6,000 mcg of allicin), divided into two or three admininstrations.
Green tea has been shown to lower total cholesterol levels and improve peoples cholesterol profile, decreasing LDL cholesterol and increasing HDL cholesterol according to preliminary studies. However, not all trials have found that green tea intake lowers lipid levels. Much of the research documenting the health benefits of green tea is based on the amount of green tea typically drunk in Asian countriesabout three cups per day, providing 240 to 320 mg of polyphenols.
An extract of green tea, enriched with a compound present in black tea (theaflavins), has been found to lower serum cholesterol in a double-blind study of people with moderately high cholesterol levels. The average reduction in total serum cholesterol during the 12-week study was 11.3%, and the average reduction in LDL cholesterol was 16.4%. The extract used in this study provided daily 75 mg of theaflavins, 150 mg of green tea catechins, and 150 mg of other tea polyphenols.
Artichoke has moderately lowered cholesterol and triglycerides in some, but not all, human trials. One double-blind trial found that 900 mg of artichoke extract per day significantly lowered serum cholesterol and LDL cholesterol but did not decrease triglycerides or raise HDL cholesterol. Cholesterol-lowering effects occurred when using 320 mg of standardized leaf extract taken two to three times per day for at least six weeks.
Berberine, a compound found in certain herbs such as goldenseal, barberry, and Oregon grape, has been found to lower serum cholesterol levels. In a study of people with high cholesterol levels, 500 mg of berberine taken twice a day for three months lowered the average cholesterol level by 29%. No significant side effects were reported, except for mild constipation.
Fenugreek seeds contain compounds known as steroidal saponins that inhibit both cholesterol absorption in the intestines and cholesterol production by the liver. Dietary fiber may also contribute to fenugreeks activity. Multiple human trials (some double-blind) have found that fenugreek may help lower total cholesterol in people with moderate atherosclerosis or those having insulin-dependent or non-insulin-dependent diabetes. One human double-blind trial has also shown that defatted fenugreek seeds may raise levels of beneficial HDL cholesterol. One small preliminary trial found that either 25 or 50 grams per day of defatted fenugreek seed powder significantly lowered serum cholesterol after 20 days. Germination of the fenugreek seeds may improve the soluble fiber content of the seeds, thus improving their effect on cholesterol. Fenugreek powder is generally taken in amounts of 10 to 30 grams three times per day with meals.
Preliminary Chinese research has found that high doses (12 grams per day) of the herb fo-ti may lower cholesterol levels. Double-blind or other controlled trials are needed to determine fo-tis use in lowering cholesterol. A tea may be made from processed roots by boiling 3 to 5 grams in a cup of water for 10 to 15 minutes. Three or more cups should be drunk each day. Fo-ti tablets containing 500 mg each are also available. Doctors may suggest taking five of these tablets three times per day.
Wild yam has been reported to raise HDL cholesterol in preliminary research. Doctors sometimes recommend 2 to 3 ml of tincture taken three to four times per day, or 1 to 2 capsules or tablets of dried root taken three times per day.
Animal studies suggest that the mushroom maitake may lower fat levels in the blood. This research is still preliminary and requires confirmation with controlled human trials.
Animal studies indicate that saponins in alfalfa seeds may block absorption of cholesterol and prevent the formation of atherosclerotic plaques. However, consuming the large amounts of alfalfa seeds (80 to 120 grams per day) needed to supply high doses of these saponins may potentially cause damage to red blood cells in the body.
Are there any side effects or interactions?
Refer to the individual herb for information about any side effects or interactions.
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Benign Prostatic Hyperplasia
Also known as BPH, this common condition is characterized by frequent urges to urinate. What can you do to relieve prostate pressure? According to research or other evidence, the following self-care steps may be helpful:
- See what saw palmetto has to offer
- Control BPH symptoms with this effective herbal remedy; take 320 mg a day of a liposterolic extract, standardized for 80 to 95% fatty acids
- Discover the benefits of beta-sitosterol
- Take 130 mg a day of this edible plant compound to improve urinary flow and other symptoms
- Try flower pollen
- Take several tablets or capsules a day of flower pollen extract to reduce symptoms
- Get to know pygeum
- Try 100 to 200 mg a day of this evergreen tree bark extract, standardized for 13% total sterols
- Focus on physical fitness
- Increase your physical activity by walking more or adding other exercise
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full benign prostatic hyperplasia article for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and lifestyle changes that may be helpful.
Benign prostatic hyperplasia (BPH) is a non-malignant enlargement of the prostate gland.
The prostate is a small gland that surrounds the neck of the bladder and urethra in men. Its major function is to contribute to seminal fluid. If the prostate enlarges, pressure may be put on the urethra, acting like a partial clamp and causing a variety of urinary symptoms. Half of all 50-year-old men have BPH, and the prevalence of the condition increases with advancing age. The name “benign prostatic hyperplasia” has replaced the older term “benign prostatic hypertrophy”; both terms refer to the same condition.
What are the symptoms?
A man with BPH has to urinate more often, especially at night, and experiences less force and caliber while urinating, often dribbling. If the prostate enlarges too much, urination is difficult or impossible, and the risk of urinary tract infection and kidney damage increases. A doctor can usually detect an enlarged prostate during a rectal exam.
Lifestyle changes that may be helpful
More physically active men have a lower frequency of symptoms related to BPH. In a preliminary study, physical activity was associated with a decrease in occurrence of BPH, surgery for BPH, and symptoms of BPH.1 Walking, the most prevalent activity among men in this study, was related to a decreased risk of BPH. Men who exercised by walking two to three hours per week had a 25% lower risk of BPH compared with men who didn’t use walking for exercise.
Other therapies
Doctors often recommend surgery when symptoms are severe or when there is a high risk of urinary obstruction. Though prostate surgery has a high success rate, it also has a higher rate of complications than drug therapy.
Vitamins that may be helpful
Beta-sitosterol, a compound found in many edible plants, has also been found to be helpful for men with BPH. In one double-blind trial, 200 men with BPH received 20 mg of beta-sitosterol three times a day or a placebo for six months. Men receiving beta-sitosterol had a significant improvement in urinary flow and an improvement in symptoms, whereas no change was reported in men receiving the placebo. Another double-blind study reported similarly positive results using 130 mg per day of beta-sitosterol.
Rye pollen extract has improved the symptoms of BPH in preliminary trials. Double-blind trials have also reported that rye pollen extract is effective for reducing symptoms of BPH This rye pollen extract was shown to be comparable in effect to an amino acid mixture used for BPH in a double-blind study. A double-blind comparison with pygeum resulted in significant subjective improvement in 78% of those given the rye pollen extract compared with 55% using pygeum. Research on this commercial rye pollen extract has used three to six tablets, or four capsules, per day; the effect of other pollens in men with prostate conditions has not yet been studied.
In a controlled trial, men with BPH received a supplement containing three amino acids (glycine, alanine, and glutamic acid) totaling about 760 mg three times per day for two weeks, then 380 mg three times per day for a total of three months. After three months, about half of these men reported reduced urgency, frequency, and/or less delay starting urine flow, compared to 15% or less of the men who received a placebo. Another similar controlled trial of this combination also reported positive results Although it is not known how the amino acid combination works, it is believed to reduce the amount of swelling in prostate tissue.
In a 1941 preliminary report, 19 men with BPH were given an essential fatty acid (EFA) supplement. In every case, the amount of retained urine was reduced, and nighttime urination problems stopped in 69% of cases. Dribbling was eliminated in 18 of the 19 men. All men also reported improved libido and a reduction in the size of the enlarged prostate, as determined by physical examination. Because this study did not include a control group and the amount given was surprisingly small, the possibility of a placebo effect cannot be ruled out.
Despite the lack of good published research, many doctors have been impressed with the effectiveness of essential fatty acids (EFAs) in cases of BPH. A typical recommendation is one tablespoon of flaxseed oil per day, perhaps reduced to one or two teaspoons per day after several months. Because taking EFAs increases the requirement for vitamin E, most doctors recommend taking a vitamin E supplement along with EFAs. However, controlled research is needed to establish whether EFAs are helpful for BPH.
Prostatic secretions are known to contain a high concentration of zinc; that observation suggests that zinc plays a role in normal prostate function. In one preliminary study, 19 men with benign prostatic hyperplasia took 150 mg of zinc daily for two months, and then 50 to 100 mg daily. In 74% of the men, the prostate became smaller. Because this study did not include a control group, improvements may have been due to a placebo effect. Zinc also reduced prostatic size in an animal study but only when given by local injection. Although the research supporting the use of zinc is weak, many doctors recommend its use. Because supplementing with large amounts of zinc (such as 30 mg per day or more) may potentially lead to copper deficiency, most doctors recommend taking 2 to 3 mg of copper per day along with zinc.
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful
In many parts of Europe, herbal supplements are considered standard medical treatment for BPH. Although herbs for BPH are available without prescription, men wishing to take them should be monitored by a physician.
The fat-soluble (liposterolic) extract of the saw palmetto berry has become the leading natural treatment for BPH. This extract, when used regularly, has been shown to help keep symptoms in check. Saw palmetto appears to inhibit 5-alpha-reductase, the enzyme that converts testosterone to its more active form, dihydrotestosterone (DHT). Saw palmetto also blocks DHT from binding in the prostate. Studies have used 320 mg per day of saw palmetto extract that is standardized to contain approximately 80 to 95% fatty acids.
A three-year preliminary study in Germany found that 160 mg of saw palmetto extract taken twice daily reduced nighttime urination in 73% of patients and improved urinary flow rates significantly. In a double-blind trial at various sites in Europe, 160 mg of saw palmetto extract taken twice per day treated BPH as effectively as finasteride without side effects, such as loss of libido. A one-year dose-comparison study found that 320 mg once per day was as effective as 160 mg twice per day in the treatment of BPH. A review of all available double-blind trials has concluded that saw palmetto is effective for treatment of men with BPH and is just as effective as, with fewer side effects than, the drug finasteride. One study found saw palmetto to be ineffective as a treatment for BPH. However, the study excluded men with mild BPH, even though previous studies had found the herb effective for mild to moderate BPH.
In a preliminary study, supplementation with a special aged garlic extract (Kastamonu Garlic) in the amount of 1 ml per 2.2 pounds of body weight per day for one month resulted in a 32% reduction in the size of the prostate gland and a significant improvement in urinary symptoms. It is not known whether other forms of garlic would have the same effect.
In a double-blind trial, an extract of Reishi mushroom (Ganoderma lucidum; 6 mg per day for 8 weeks) was significantly more effective than a placebo in improving urinary symptoms in men with BPH. Reishi extract appears to work by inhibiting 5-alpha-reductase, the enzyme that converts testosterone to its more active form, dihydrotestosterone (DHT).
Pygeum, an extract from the bark of the African tree, has been approved in Germany, France, and Italy as a remedy for BPH. Controlled studies published over the past 25 years have shown that pygeum is safe and effective for men with BPH of mild or moderate severity. These studies have used 50 to 100 mg of pygeum extract (standardized to contain 13% total sterols) twice per day. This herb contains three compounds that may help the prostate: pentacyclic triterpenoids, which have a diuretic action; phytosterols, which have anti-inflammatory activity; and ferulic esters, which help rid the prostate of any cholesterol deposits that accompany BPH.
Another herb for BPH is a concentrated extract made from the roots of the nettle plant. This extract may increase urinary volume and the maximum flow rate of urine in men with early-stage BPH. It has been successfully combined with both saw palmetto and pygeum to treat BPH in double-blind trials. It has also been shown in a double-blind trial, when used by itself, to relieve symptoms of BPH and to improve disease severity. An appropriate amount appears to be 120 mg of nettle root extract (in capsules or tablets) twice per day or 2 to 4 ml of tincture three times per day.
Pumpkin seed oil has been used in combination with saw palmetto in two double-blind human studies to effectively reduce symptoms of benign prostatic hyperplasia (BPH).30 Only one group of researchers has evaluated the effectiveness of pumpkin seed oil alone for BPH, but the results of their large preliminary trials have been favorable. Researchers have suggested the zinc, free fatty acid, or plant sterol content of pumpkin seeds may account for their benefit in men with BPH, but this has not been confirmed. Animal studies have shown that pumpkin seed extracts may improve the function of the bladder and urethra; this might partially account for BPH symptom relief. Pumpkin seed oil extracts standardized for fatty acid content have been used in BPH studies in the amount of 160 mg three times per day with meals.
Are there any side effects or interactions?
Refer to the individual herb for information about any side effects or interactions.
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Immune System
The immune system is a complex network of tissues, organs, cells, and chemicals that protects the body from infection and illness. According to research or other evidence, the following self-care steps may help boost your built-in bodyguard:
- Aim for total nutrition with a multivitamin
- Get extra vitamins and minerals every day to help prevent deficiencies that make you a target for infections
- Use exercise wisely
- Take advantage of the benefits of moderate exercise on immune functionbut be careful about prolonged or intense exercise, which can temporarily increase your risk of infection
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Update your vaccinations
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Consult your medical provider to see if you need vaccines for influenza, pneumonia, hepatitis, tetanus, and other infections
About immune function
The immune system is an intricate network of specialized tissues, organs, cells, and chemicals. The lymph nodes, spleen, bone marrow, thymus gland, and tonsils all play a role, as do lymphocytes (specialized white blood cells), antibodies, and interferon.
Two types of immunity protect the body: innate and adaptive. Innate immunity is present at birth and provides the first barrier against microorganisms. The skin, mucus secretions, and the acidity of the stomach are examples of innate immunity that act as barriers to keep unwanted germs away from more vulnerable tissues.
Adaptive immunity is the second barrier to infection. It is acquired later in life, such as after an immunization or successfully fighting off an infection. The adaptive immune system retains a memory of all the invaders it has faced. This is why people usually get the measles only once, although they may be repeatedly exposed to the disease. Unfortunately some bugssuch as the viruses that cause the common colddisguise themselves and must be fought off time and again by the immune system.
What are the symptoms?
Symptoms of decreased immune function include frequent colds and flus, recurring parasitic infections, initially mild infections that become serious, opportunistic infections (infections by organisms that are usually well controlled by a healthy immune system, such as toxoplasmosis, cryptococcosis, and cytomegalovirus), and cancer.
Dietary changes that may be helpful
All forms of sugar (including honey) interfere with the ability of white blood cells to destroy bacteria. Animal studies suggest diets high in sucrose (table sugar) impair some aspects of immune function. The importance of these effects in the prevention of infections in humans remains unclear.
Alcohol intake, including single episodes of moderate consumption, interferes with a wide variety of immune defenses. Alcohols immune-suppressive effect may be one mechanism for the association between alcohol intake and certain cancers and infections. However, moderate alcohol consumption (up to three to four drinks per day) has been associated in preliminary studies with either no risk or a decreased risk for upper respiratory infections in young nonsmokers.
The effect of fats on the immune system is complex and only partially understood. Excessive intake of total dietary fat impairs immune response, but some types of fat may be neutral or even beneficial. For example, monounsaturated fats, as found in olive oil, appear to have no detrimental effect on the immune system in humans at reasonable dietary levels.
Research on the effect of the omega-3 fatty acids that are abundant in some fish, fish oils, and flaxseed oil is conflicting. Liquid diets containing omega-3 fatty acids used in hospitals for critically ill people have been shown to improve immune function and reduce infections. However, in one controlled study in healthy people, a low-fat diet improved or maintained immune function, but when fish was added to increase omega-3 fatty acid intake, immune function was significantly inhibited.
Supplementation with DHA (an omega-3 fatty acid found in fish oil) in healthy young men has been shown to decrease the activity of immune cells, such as natural killer (NK) cells, and to inhibit certain measures of inflammation in the test tube. The anti-inflammatory effects of DHA may be useful in the management of autoimmune disorders; however, such benefits need to be balanced with the potential for increased risk of infections. Other studies suggest that increased oxidative damage might be the reason for the negative effects on the immune system sometimes caused by fish oil, and that increased intake of antioxidants, such as vitamin E, could correct the problem.
As with omega-3 fatty acids, omega-6 fatty acids (as found in vegetable oils) have also produced conflicting effects on the immune system. Enriching a low-fat diet with omega-6 fatty acids did not impair immunity. However, diets high in omega-6 fatty acids have suppressed immunity in other reports.
In summary, low-fat diets with moderate levels of monounsaturated fat from olive oil appear least likely to compromise immune function and may provide small benefits. Conclusions about the desirability of diets high in either omega-3 or omega-6 fatty acid supplementation await further research.
Many studies, in both animals and humans, have demonstrated immune-stimulating effects from yogurt which contains live cultures, such as Lactobacillus acidophilus and other probiotics (friendly bacteria). The effects of probiotics observed in humans include increasing the activity of several types of white blood cells. In preliminary human studies, consumption of live probiotic-containing yogurt has been associated with a reduced incidence of several immune-related diseases, including cancer, infections of the stomach and intestines, and some allergic reactions.
Lifestyle changes that may be helpful
Both excessive thinness and severe obesity are associated with impaired immune responses. Obesity increases the risk of infection, at least in hospitalized patients, according to preliminary research. However, these effects may not occur with mild to moderate obesity in otherwise healthy people, and attempts to lose weight through dietary restriction may actually be harmful to the immune system. The detrimental effects of both appear to be offset when people regularly perform aerobic exercise.
The effects of exercise on immune function depend on many factors, including frequency and intensity of exercise. Regular moderate physical activity has positive effects, at least on some measures of immunity, and has been shown to reduce risk of upper respiratory infection. However, very intense and prolonged exercise, such as running a marathon or overtraining, can, in the short term, actually increase the risk of developing infections. The positive effects of moderate exercise on immunity may also partly explain the apparent reduced susceptibility to cancer of physically active people.
Other therapies
Treatment for decreased immune functioning also includes vaccination for the flu, pneumococcus (a cause of pneumonia), hepatitis, tetanus, and other infections combined with precautions to reduce exposure to infectious agents.
Vitamins that may be helpful
Most, but not all, double-blind studies have shown that elderly people have better immune function and reduced infection rates when taking a multiple vitamin-mineral formula. In one double-blind trial, supplements of 100 mcg per day of selenium and 20 mg per day of zinc, with or without additional vitamin C, vitamin E, and beta-carotene, reduced infections in elderly people, though vitamins without minerals had no effect. Burn victims have also experienced fewer infections after receiving trace mineral supplements in double-blind research. These studies suggest that trace minerals may be the most important micronutrients for enhancing immunity and preventing infections in the elderly.
Vitamin E enhances some measures of immune-cell activity in the elderly. This effect is more pronounced with 200 IU per day compared with either lower (60 IU per day) or higher (800 IU per day) amounts, according to double-blind research. Intakes under 200 IU per day have not boosted immune function in some reports.
Beta-carotene and other carotenoids have increased immune cell numbers and activity in animal and human research, an effect that appears to be separate from their role as precursors to vitamin A. Placebo-controlled research has shown positive benefits of beta-carotene supplements in increasing numbers of some white blood cells and enhancing cancer-fighting immune functions in healthy people at 25,000100,000 IU per day.
In double-blind trials in the elderly, supplementation with 40,000150,000 IU per day of beta-carotene has increased natural killer (NK) cell activity, but not several other measures of immunity.
Controlled research has found that 50,000 IU per day of beta-carotene boosted immunity in people with colon cancer but in not those with precancerous conditions in the colon. Beta-carotene has also prevented immune suppression from ultraviolet light exposure. Effects on immunodefiency in HIV-positive people have been inconsistent using beta-carotene.
Vitamin C stimulates the immune system by both elevating interferon levels and enhancing the activity of certain immune cells. Two studies came to opposite conclusions about the ability of vitamin C to improve immune function in the elderly, and two other studies did not agree on whether vitamin C could protect people from hepatitis. However, a review of 20 double-blind studies concluded that while several grams of vitamin C per day has only a small effect in preventing colds, when taken at the onset of a cold, it does significantly reduce the duration of a cold. In controlled reports studying people doing heavy exercise, cold frequency was reduced an average of 50% with vitamin C supplements ranging from 600 to 1,000 mg per day. Thus, the overall effect of vitamin C on immune function is unclear, and its usefulness may vary according to the situation.
Vitamin A plays an important role in immune system function and helps mucous membranes, including those in the lungs, resist invasion by microorganisms. However, most research shows that while vitamin A supplementation helps people prevent or treat infections in developing countries where deficiencies are common, little to no positive effect, and even slight adverse effects, have resulted from giving vitamin A supplements to people in countries where most people consume adequate amounts of vitamin A. Moreover, vitamin A supplementation during infections appears beneficial only in certain diseases. An analysis of trials revealed that vitamin A reduces mortality from measles and diarrhea, but not from pneumonia, in children living in developing countries. A double-blind trial of vitamin A supplementation in Tanzanian children with pneumonia confirmed its lack of effectiveness for this condition. In general, parents in the developed world should not give vitamin A supplements to children unless there is a reason to believe vitamin A deficiency is likely, such as the presence of a condition causing malabsorption (e.g., celiac disease). However, the American Academy of Pediatrics recommends that all children with measles be given short-term supplementation with high-dose vitamin A in cases of hospitalization, malnutrition, and other special circumstances determined by a doctor.
A combination of antioxidants vitamin A, vitamin C, and vitamin E significantly improved immune cell number and activity compared with placebo in a group of hospitalized elderly people. Daily intake of a 1,000 mg vitamin C plus 200 IU vitamin E for four months improved several measures of immune function in a preliminary study. To what extent immune-boosting combinations of antioxidants actually reduce the risk of infection remains unknown.
The amino acid glutamine is important for immune system function. Liquid diets high in glutamine have been reported in controlled studies to be more helpful to critically ill people than other diets. Endurance athletes are susceptible to upper respiratory tract infections after heavy exercise, which depletes glutamine levels in blood. Although the effects of glutamine supplementation on immune function after exercise have been inconsistent, a double-blind study giving athletes glutamine (2.5 grams after exercise and again two hours later) reported significantly fewer infections with glutamine.
Supplements of probiotics (friendly bacteria) such as Lactobacillus acidophilus, or the growth factors that encourage their development in the gastrointestinal tract may help protect the body from harmful organisms in the intestine that cause local or systemic infection according to published research, including controlled trials. The effective amount of probiotics depends on the strain used, as well as the number of viable organisms. Infectious diarrhea in children has been successfully reduced with supplements of friendly bacteria in several trials, some of which were double-blind.
The thymus gland is responsible for many immune system functions. Preliminary studies suggest that a thymus extract known as Thymomodulin. may improve immune function, and double-blind trials in children and adults with a history of recurrent respiratory-tract infections have found reduced numbers of recurrent infections with Thymomodulin supplementation. Thymomodulin has also been shown in a double-blind study to improve immune function in cases of exercise-induced immune suppression, and in preliminary studies to improve immune function in people with diabetes and in elderly people.
Zinc supplements have been reported to increase immune function. This effect may be especially important in the elderly according to double-blind studies. Some doctors recommend zinc supplements for people with recurrent infections, suggesting 25 mg per day for adults and lower amounts for children (depending on body weight). However, too much zinc (300 mg per day) has been reported to impair immune function.
While zinc lozenges have been shown to be effective for reducing the symptoms and duration of the common cold in some controlled studies, it is not clear whether this effect is due to an enhancement of immune function or to the direct effect of zinc on the viruses themselves.
Large amounts of the carotenoid lycopene have been shown to increase the activity of NK cells in the elderly. In a controlled trial, 15 mg of lycopene significantly increased NK cell concentration, but no other immune functions.
A deficiency of vitamin B12 has been associated with decreased immune function. In a controlled trial, people with vitamin B12 deficiency anemia were also found to have markedly decreased levels of white blood cells associated with immune function. Restoration of vitamin B12 stores by means of injections improved levels of these immune cells, suggesting an important role for vitamin B12 in immune function.
Beta-glucan is a fiber-type polysaccharide (complex sugar) derived from the cell wall of bakers yeast, oat and barley fiber, and many medicinal mushrooms, such as maitake. Numerous experimental studies in test tubes and animals have shown beta-glucan to activate white blood cells. In fact, there have been hundreds of research papers on beta-glucan since the 1960s. The research indicates that beta-1,3-glucan, in particular, is very effective at activating white blood cells known as macrophages and neutrophils. A beta-glucanactivated macrophage or neutrophil can recognize and kill tumor cells, remove cellular debris resulting from oxidative damage, speed up recovery of damaged tissue, and further activate other components of the immune system. Although the research in test tube and animal studies is promising, many questions remain about the effectiveness of beta-glucan as an oral supplement to enhance immune function in humans. Controlled trials are necessary to determine whether humans can benefit from beta-glucan, and in what amounts oral beta-glucan must be taken from meaningful effects.
The hormone DHEA effects immunity. In a controlled trial, a group of elderly men with low DHEA levels who were given a high level of DHEA (50 mg per day) for 20 weeks, experienced a significant activation of immune function. Postmenopausal women have also shown increased immune functioning in just three weeks when given DHEA in double-blind research.
The effects of eating fish and other dietary sources of omega-3 fatty acids is discussed above in the nutritional section. In terms of fish oil supplements, except for effects in hospitalized patients, most studies have reported that additional omega-3 intake decreases immune function. Antioxidants may correct this problem, according to preliminary research.
Liquid diets containing supplemental arginine, omega-3 fatty acids, and nucleotides such as ribonucleic acid (RNA) have been more effective than other liquid diets in both maintaining immune function and reducing infections in critically ill and post-surgical hospital patients in most, but not all, double-blind trials. Typical daily intakes in these trials are 3.3 grams of omega 3 fatty acids, 12.5 grams of arginine, and 1.2 grams of RNA. No research has studied the effects of these supplements in people with less severe health problems.
A double-blind trial showed that 45 grams per day of whey protein increased blood glutathione levels in a group of HIV-infected people. Test tube and animal studies suggest that whey protein may improve some aspects of immune function.
Herbs that may be helpful
In general, human studies have found that echinacea taken orally stimulates the function of a variety of immune cells, particularly natural killer cells. The balance of evidence currently available from studies suggests that echinacea speeds recovery from the common cold, via immune stimulation (as opposed to killing the cold virus directly). Evidence on preventing the common cold with echinacea is largely negative, suggesting its immune-stimulating activity may be mild in generally healthy people. Other studies on oral echinacea have not found that it stimulates activity of the white blood cells known as neutrophils. Many doctors recommend 3 to 5 ml of tincture three times per day for up to two weeks to improve immune function. Echinacea in capsule form is also commonly available.
Andrographis has been shown in a double-blind trial to successfully reduce the severity of the common cold. A preliminary study also suggests it may prevent the onset of a cold in healthy people. These actions are thought to be due to the immune system enhancing actions of the active constituents known as andrographolides.
Asian ginseng has a long history of use in traditional herbal medicine for preventing and treating conditions related to the immune system. A double-blind study of healthy people found that taking 100 mg of a standardized extract of Asian ginseng twice per day improved immune function.
Eleuthero (Siberian ginseng) has also historically been used to support the immune system. Preliminary Russian research has supported this traditional use. A double-blind study has shown that healthy people who take 10 ml of eleuthero tincture three times per day had an increase in certain T lymphocytes important to normal immune function. These effects have not been studied in people with lowered immune function. The amount of eleuthero used in this trial is exceptionally high, though no side effects were seen.
Ashwagandha is considered a general stimulant of the immune system, and has been called a tonic or adaptogen an herb with multiple, nonspecific actions that counteract the effects of stress and generally promote wellness. More research is needed to better evaluate these claims.
Complex polysaccharides present in astragalus and in maitake and coriolus mushrooms appear to act as immunomodulators and, as such, are being researched for their potential role in AIDS and cancer. Presently, the only human studies on astragalus indicate that it can prevent white blood cell numbers from falling in people given chemotherapy and radiotherapy and can elevate antibody levels in healthy people. Maitake has only been studied in animals as a way to increase immune function. The primary immuno-activating polysaccharide found in these mushrooms, beta-D-glucan, is well absorbed when taken orally138 and is currently under investigation as a supportive tool for HIV infection. Results from future research will improve the understanding of the possible benefits of these mushrooms and their constituents.
Substances found in cats claw, called oxyindole alkaloids have been shown to stimulate the immune system.139 However, little is known about whether this effect is sufficient to prevent or treat disease.
Cordyceps has immune strengthening actions in human and animal studies. Further research is needed but it may be helpful in a wide range of conditions in which the immune system is weakened. The usual amount taken is 3 to 4.5 grams twice daily as capsules or simmered for 10 to 15 minutes in water for tea.
Green tea has stimulated production of immune cells and has shown anti-bacterial properties in animal studies. More research is needed to evaluate the effectiveness of green tea in protecting against infection and other immune system-related diseases.
Preliminary research suggests that fo-ti plays a role in a strong immune system and has antibacterial action. More research is needed to further understand the potential importance of these effects.
The main active compound in ligustrum is ligustrin (oleanolic acid). Studies, mostly conducted in China, suggest that ligustrum stimulates the immune system. Ligustrum is often combined with astragalus in traditional Chinese medicine. Although used for long-term support of the immune system in people with depressed immune function or cancer, more research is needed to demonstrate the optimal length of time to use ligustrum.
Animal and test tube studies show noni to have some immune-enhancing activity. Specifically, the polysaccharide component has been shown to increase the release of immune-enhancing compounds that activate white blood cells to destroy tumor cells. The usual recommendation is 4 ounces of noni juice 30 minutes before breakfast (effectiveness is thought to be best on an empty stomach). Human studies are needed to confirm the usefulness of noni.
Holistic approaches that may be helpful
The immune system is suppressed during times of stress. Chronic mental and emotional stress can reduce immune function, but whether this effect is sufficient to increase the risk of infection or cancer is less clear. Nevertheless, immune function has been increased by stress-reducing techniques such as relaxation exercises, biofeedback, and other approaches, although not all studies have shown a significant effect.
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist.
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Copyright ) 2007 Healthnotes, Inc. All rights reserved. www.healthnotes.com
Heart Disease
A heart-to-heart on cardiovascular disease: Make simple changes to help you beat the odds against heart disease, a leading cause of death. According to research or other evidence, the following self-care steps may be helpful:
- Get smoke-free
- Quit smoking and stay clear of cigarette smoke to lower your risk of several types of cardiovascular disease
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Watch what you eat
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Eat lots of fruits, vegetables, legumes, whole grains, fish, and avoid fats from meat, dairy, and processed foods high in hydrogenated oils
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full cardiovascular disease article for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and lifestyle changes that may be helpful.
About cardiovascular disease
Cardiovascular disease is a wide-encompassing category that includes all conditions that affect the heart and the blood vessels.
Cardiovascular disease is the number one cause of death in the United States. This introductory article briefly discusses several diseases that have a role in the development of cardiovascular disease. Many risk factors are associated with cardiovascular disease; most can be managed, but some cannot. The aging process and hereditary predisposition are risk factors that cannot be altered. Until age 50, men are at greater risk than women of developing heart disease, though once a woman enters menopause, her risk triples.
Many people with cardiovascular disease have elevated or high cholesterol levels. Low HDL cholesterol (known as the "good" cholesterol) and high LDL cholesterol (known as the "bad" cholesterol) are more specifically linked to cardiovascular disease than is total cholesterol. A blood test, administered by most healthcare professionals, is used to determine cholesterol levels.
Atherosclerosis (hardening of the arteries) of the vessels that supply the heart with blood is the most common cause of heart attacks. Atherosclerosis and high cholesterol usually occur together, though cholesterol levels can change quickly and atherosclerosis generally takes decades to develop.
The link between high triglyceride levels and heart disease is not as well established as the link between high cholesterol and heart disease. According to some studies, a high triglyceride level is an independent risk factor for heart disease in some people.
High homocysteine levels have been identified as an independent risk factor for heart disease. Homocysteine can be measured by a blood test that must be ordered by a healthcare professional.
Hypertension (high blood pressure) is a major risk factor for cardiovascular disease, and the risk increases as blood pressure rises. Glucose intolerance and diabetes constitute separate risk factors for heart disease. Smoking increases the risk of heart disease caused by hypertension.
Abdominal fat, or a "beer belly," versus fat that accumulates on the hips, is associated with increased risk of cardiovascular disease and heart attack. Overweight individuals are more likely to have additional risk factors related to heart disease, specifically hypertension, high blood sugar levels, high cholesterol, high triglycerides, and diabetes.
What are the symptoms?
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People with cardiovascular disease may not have any symptoms, or they may experience difficulty in breathing during exertion or when lying down, fatigue, lightheadedness, dizziness, fainting, depression, memory problems, confusion, frequent waking during sleep, chest pain, an awareness of the heartbeat, sensations of fluttering or pounding in the chest, swelling around the ankles, or a large abdomen.
Dietary changes that may be helpful
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Preliminary evidence has linked high salt consumption with increased cardiovascular disease incidence and death among overweight, but not normal weight, people. Among overweight people, an increase in salt consumption of 2.3 grams per day was associated with a 32% increase in stroke incidence, an 89% increase in stroke mortality, a 44% increase in heart disease mortality, a 61% increase in cardiovascular disease mortality, and a 39% increase in death from all causes. Intervention trials are required to confirm these preliminary observations.
Moderate alcohol consumption appears protective against heart disease. However, regular, light alcohol consumption in men with established coronary heart disease is not associated with either benefit or deleterious effect.
A high intake of carotenoids from dietary sources has been shown to be protective against heart disease in several population-based studies. A diet high in fruits and vegetables, fiber, and possibly fish appears protective against heart disease, while a high intake of saturated fat (found in meat and dairy fat) and trans fatty acids (in margarine and processed foods containing hydrogenated vegetable oils) may contribute to heart disease. In a preliminary study, the total number of deaths from cardiovascular disease was significantly lower among men with high fruit consumption than among those with low fruit consumption. A large study of male healthcare professionals found that those men eating mostly a "prudent" diet (high in fruits, vegetables, legumes, whole grains, fish, and poultry) had a 30% lower risk of heart attacks compared with men who ate the fewest foods in the "prudent" category. By contrast, men who ate the highest percentage of their foods from the "typical American diet" category (high in red meat, processed meat, refined grains, sweets, and desserts) had a 64% increased risk of heart attack, compared with men who ate the fewest foods in that category. The various risks in this study were derived after controlling for all other beneficial or harmful influencing factors.
A parallel study of female healthcare professionals showed a 15% reduction in cardiovascular risk for those women eating a diet high in fruits and vegetablescompared with those eating a diet low in fruits and vegetables.
Lifestyle changes that may be helpful
Both smoking20 and exposure to secondhand smoke increase cardiovascular disease risk.
Moderate exercise protects both lean and obese individuals from cardiovascular disease.
Other therapies
Surgical treatments, such as angioplasty, bypass surgery, valve replacement, pacemaker installation, and heart transplantation, may be recommended for severe cases. Individuals with cardiovascular disease are strongly encouraged to stop smoking.
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Athlete’s foot? The toes will tell you. A persistent, burning itch between the toes can send you running for relief. According to research or other evidence, the following self-care steps may be helpful:
- Keep it dry
- To discourage fungal growth, dry feet thoroughly after showering or bathing, use foot powders, and change socks frequently
- Let your feet see the light
- Wear sandals or other open footwear to expose skin to sunlight’s antifungal effects
- Try tea tree oil
- Apply a 10% herbal concentration in a cream base as a natural alternative to antifungal medications
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full athlete’s foot article for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and lifestyle changes that may be helpful.
About athlete’s foot
Athlete’s foot is a fungal infection of the foot that can be caused by a number of different skin fungi.
Generally, athlete’s foot does not cause serious problems; however, the disruption of the skin barrier can be a source of significant infections in people with impaired blood flow to the feet (such as people with diabetes) or in those with impaired immune systems. Infections of the nails are more difficult to treat than those affecting only the skin.
What are the symptoms?
Symptoms of athlete’s foot include a persistent, burning itch that often starts between the toes. The skin on the feet may be damp, soft, red, cracked, or peeling; the feet may also show patches of dead skin. The feet often have a strong or unusual smell, and sometimes small blisters occur on the feet.
Lifestyle changes that may be helpful
Keeping the feet dry is very important for preventing and fighting athlete’s foot. After showering or bathing, thorough drying or careful use of a hair dryer is recommended. Light is also an enemy of fungi. People with athlete’s foot should change socks daily to decrease contact with the fungus and should wear sandals occasionally to get sunlight exposure.
Other therapies
Drying powders can be used inside the socks and shoes to help keep the feet dry during the day.
Herbs that may be helpful
Tea tree oil has been traditionally used to treat athlete’s foot. One trial reported that application of a 10% tea tree oil cream reduced symptoms of athlete’s foot just as effectively as drugs and better than placebo, although it did not eliminate the fungus.1
The compound known as ajoene, found in garlic, is an antifungal agent. In a group of 34 people using a 0.4% ajoene cream applied once per day, 79% of them saw complete clearing of athlete’s foot after one week; the rest saw complete clearing within two weeks.2 All participants remained cured three months later. One trial found a 1% ajoene cream to be more effective than the standard topical drug terbinafine for treating athlete’s foot.3 Ajoene cream is not yet available commercially, but topical application of crushed, raw garlic may be a potential alternative application.
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Reach the peak of athletic performance. Take your game to the next level by learning some fitness essentials. According to research or other evidence, the following self-care steps may be helpful:
- Eat more carbs
- Supply the body with efficient energy fuel found in grains, starchy vegetables, fruits, low-fat dairy products, and carbohydrate-replacement drinks
- Get enough water and electrolytes
- Water is crucial for all sports activities—electrolytes are only important for extreme endurance exercise
- Check out creatine monohydrate
- Take 15 to 20 grams a day of this supplement for five or six days to improve performance of high-intensity, short-duration exercise (like sprinting) or sports with alternating low- and high-intensity efforts
- Take a multivitamin
- When your diet isn’t enough, extra vitamins and minerals will help your body get the nutrition it needs for exercise
- Try vitamin C
- Take 400 mg a day for several days before and after intense exercise to reduce pain and speed muscle strength recovery
These recommendations are not comprehensive and are not intended to replace the advice of your doctor or pharmacist. Continue reading the full athletic performance article for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and lifestyle changes that may be helpful.
About athletic performance
Aside from training, nutrition may be the most important influence on athletic performance. However, in seeking a competitive edge, athletes are often susceptible to fad diets or supplements that have not been scientifically validated. Nevertheless, there is much useful research to guide the exerciser toward optimum health and performance. Dietary changes that may be helpful
Calories
Calorie requirements for athletes depend on the intensity of their training and performance. The athlete who trains to exhaustion on a daily basis needs more fuel than one who performs a milder regimen two or three times per week. Calorie requirements can be as much as 23 to 39 calories per pound of body weight per day for the training athlete who exercises vigorously for several hours per day. Many athletes compete in sports having weight categories (such as wrestling and boxing), sports that favor small body size (such as gymnastics and horse racing), or sports that may require a specific socially accepted body shape (such as figure skating). These athletes may feel pressured to restrict calories to extreme degrees to gain a competitive edge. Excessive calorie restriction can result in chronic fatigue, sleep disturbances, reduced performance, impaired ability for intensive training, and increased vulnerability to injury.
Carbohydrates
Carbohydrates are the most efficient fuel for energy production and can also be stored as glycogen in muscle and liver, functioning as a readily available energy source for prolonged, strenuous exercise. For these reasons, carbohydrates may be the most important nutrient for sports performance. Depending on training intensity and duration, athletes require up to 4.5 grams of carbohydrates per day per pound of body weight or 60 to 70% of total dietary calories from carbohydrates, whichever is greater. Emphasizing grains, starchy vegetables, fruits, low-fat dairy products, and carbohydrate-replacement beverages, along with reducing intake of fatty foods, results in a relatively high-carbohydrate diet.
Carbohydrate beverages should be consumed during endurance training or competition (30 to 70 grams of carbohydrate per hour) to help prevent carbohydrate depletion that might otherwise occur near the end of the exercise period. Standard sport drinks containing 6 to 8% carbohydrates can be used during exercise to support both carbohydrate and fluid needs, but these should not contain large amounts of fructose, which can cause gastrointestinal distress. At the end of endurance exercise, body carbohydrate stores must be replaced to prepare for the next session. This replacement can be achieved most rapidly if 40 to 60 grams of carbohydrate are consumed right after exercise, repeating this intake every hour for at least five hours after the event. High-density carbohydrate beverages containing 20 to 25% carbohydrate are useful for immediate post-exercise repletion.
Adding protein to carbohydrate intake immediately after exercise may be helpful for improving recovery of glycogen (carbohydrate) stores after exercise according to some, though not all, controlled studies. It appears that adding protein during the post-exercise period is not necessary when carbohydrate intake is high enough (about 0.55 grams per pound of body weight).
Carbohydrate loading, or “super-compensation,” is a pre-event strategy that improves performance for some endurance athletes. Carbohydrate-loading can be achieved by consuming a 70% carbohydrate diet (or 4.5 grams per pound of body weight) for three to five days before competition, while gradually reducing training time, and ending with a day of no training while continuing the diet until the event date.
Glycemic index
The glycemic index (GI) is a measure of the ability of a food to raise blood sugar levels after it is eaten. Attention to the GI of carbohydrate sources may be helpful for increasing sports performance. Within one hour before exercise, consuming low GI carbohydrates (such as most fruits, pasta, legumes, or rice) provides carbohydrate without triggering a rapid rise in insulin that could result in hypoglycemia and prevent release of energy sources from fat cells. Some controlled studies of cycling endurance have found that eating a pre-exercise meal of low-GI foods (lentils, rolled oats, or a combination of low GI foods) is more effective than consuming high-GI foods (potatoes, puffed rice, or a combination of high GI foods), but most studies have found no significant advantage of low GI foods or fructose (a low-GI sugar) compared with other carbohydrate sources in a pre-exercise meal. After exercise, on the other hand, high-GI foods and beverages may be most helpful for quickly restoring depleted glycogen stores.
Protein
Protein requirements are often higher for both strength and endurance athletes than for people who are not exercising vigorously; however, the increased food intake needed to supply necessary calories and carbohydrates also supplies extra protein. As long as the diet contains at least 12 to 15% of calories as protein, or up to 0.75 grams per day per pound of body weight, protein supplements are neither necessary, nor likely to be of benefit. Concerns have been raised that the very high-protein diets sometimes used by body builders could put stress on the kidneys, potentially increasing the risk of kidney disease later in life. A preliminary study of male athletes consuming at least 2.77 grams per pound of body weight per day showed no evidence of kidney impairment; however, the study was limited to one month, and evidence of long-term kidney problems associated with chronic protein loading were not examined.
Preliminary studies have suggested that increased protein intake may have biological effects that could improve muscle growth resulting from strength training, especially if liquid supplements (typically containing at least 6 grams of protein or amino acids in addition to varying amounts of carbohydrate) are taken either immediately after exercise or just before exercise. However, controlled studies have found no advantage of protein supplementation (up to about 100 grams per day or about 14 grams immediately following exercise) for improving strength or body composition as long as the diet already supplies typical amounts of protein and calories.
Fat
Some athletes have speculated that consuming a high-fat diet for two or more weeks prior to endurance competition might cause the body to shift its fuel utilization toward more abundant fat stores ("fat adaptation"). However, neither short-term nor long-term use of high-fat diets has been found to improve endurance performance compared with high-carbohydrate diets, and may even be detrimental due to depletion of glycogen stores.
Following a high-fat diet with at least 24 hours of high carbohydrate intake has been suggested as a way to achieve fat adaptation while restoring glycogen levels before endurance competition. While this concept is supported by physiological studies on athletes, no actual performance enhancement was shown when athletes were tested in competitive situations after a five- to six-day high-fat diet followed by 24 hours of high carbohydrate intake. However, one controlled study found a small, significant benefit of ten days of high fat intake followed by three days of high carbohydrate intake.
Water
Water is the most abundant substance in the human body and is essential for normal physiological function. Water loss due to sweating during exercise can result in decreased performance and other problems. Fluids should be consumed prior to, during, and after exercise, especially when extreme conditions of climate, exercise intensity, and exercise duration exist. Approximately two glasses of fluid should be consumed two hours before exercise and at regular intervals during exercise; fluid should be cool, not cold (59 to 72° F, 15 to 22.2° C). Flavored sports drinks containing electrolytes are not necessary for fluid replacement during brief periods of exercise, but they may be more effective in encouraging the athlete to drink frequently and in larger amounts.
Lifestyle changes that may be helpful
Many athletes use exercise and weight-modifying diets as tools to change their body composition, assuming that a lower percentage of body fat and/or higher lean body mass is desirable in any sport. There is no single standard for body weight and body composition that applies to all types of athletic activities. Different sports, even different roles in the same sport (e.g., running vs. blocking in football), require different body types. These body types are largely determined by genetics. However, within each athlete’s genetic predisposition, variations result from diet and exercise that may affect performance. In general, excess weight is a disadvantage in activities that require quickness and speed. However, brief, intense bursts of power depend partly on muscle size, so this type of activity may favor athletes with greater muscle mass. On the other hand, participants in endurance sports, which require larger energy reserves, should not attempt to lower their body fat so much as to compromise their performance.
Other therapies
Athletic performance may be improved by ensuring adequate and balanced nutrition, sufficient fluid intake, and proper rest. The avoidance of performance-reducing drugs such as alcohol and tobacco is also commonly recommended.
Vitamins that may be helpful
AAKG
AAKG (arginine alpha-ketoglutarate) is a compound made from the amino acid L-arginine and alpha-ketoglutarate (AKG) a substance formed in the body’s energy-generating process. It has been speculated that AAKG may increase production in muscles of nitric oxide, a substance known to have blood-flow-enhancing effects. A double-blind study gave trained weight lifters either 4 grams of AAKG or a placebo three times a day during an eight-week weight-training regimen. AAKG had no effect on body composition but did improve measures of strength and short-term power performance.
Creatine
Creatine (creatine monohydrate) is used in muscle tissue for the production of phosphocreatine, a factor in the formation of ATP, the source of energy for muscle contraction and many other functions in the body. Creatine supplementation increases phosphocreatine levels in muscle, especially when accompanied by exercise or carbohydrate intake. It may also increase exercise-related gains in lean body mass, though it is unclear how much of these gains represents added muscle tissue and how much is simply water retention.
Over 40 double-blind or controlled studies have found creatine supplementation (typically 136 mg per pound of body weight per day or 15 to 25 grams per day for five or six days) improves performance of either single or repetitive bouts of short-duration, high-intensity exercise lasting under 30 seconds each. Examples of this type of exercise include weightlifting; sprinting by runners, cyclists, or swimmers; and many types of athletic training regimens for speed and power. About 15 studies did not report enhancement by creatine of this type of performance. These have been criticized for their small size and other research design problems, but it is possible that some people, especially elite athletes, are less likely to benefit greatly from creatine supplementation.
Fewer studies have investigated whether creatine supplementation benefits continuous high- intensity exercise lasting 30 seconds or longer. Five controlled studies have found creatine beneficial for this type of exercise, but one study found no benefit on performance of a military obstacle course run. Most studies of endurance performance have found no advantage of creatine supplementation, except perhaps for non-weight bearing exercise such as cycling. Long-term use of creatine supplementation is typically done using smaller daily amounts (2 to 5 grams per day) after an initial loading period of several days with 20 grams per day. Very little research has been done to investigate the exercise performance effects of long-term creatine supplementation. One study reported that long-term creatine supplementation improved sprint performance. Four controlled long-term trials using untrained women, trained men, or untrained older adults found that creatine improved gains made in strength and lean body mass from weight-training programs. However, two controlled trials found no advantage of long-term creatine supplementation in weight-training football players.
Creatine supplementation appears to increase body weight and lean body mass or fat-free mass, but these measurements do not distinguish between muscle growth and increased water content of muscle. A few double-blind studies using more specific muscle measurements have been done and found that combining creatine supplementation with strength training over several weeks does produce greater increases in muscle size compared with strength training alone. Multivitamin-mineral supplements
Many athletes do not eat an optimal diet, especially when they are trying to control their weight while training strenuously. These athletes may experience micronutrient deficiencies that, even if marginal, could affect performance or cause health problems. However, athletes who receive recommended daily allowances of vitamins and minerals from their diet do not appear to benefit from additional multivitamin-mineral supplements with increased performance. Very little research has been done to evaluate the ergogenic effects of most vitamins or minerals other than those discussed in this article. Supplementation with selenium (180 mcg per day for 10 weeks) had no effect on the results of endurance training in one double-blind trial. Vanadyl sulfate, a form of vanadium that may have an insulin-like action, was given to weight-training athletes in a double-blind trial, using 225 mcg per pound of body weight per day, but no effect on body composition was seen after 12 weeks, and effects on strength were inconsistent. The importance of other individual vitamins and minerals is discussed elsewhere in this section.
Antioxidants
Most research has demonstrated that strenuous exercise increases production of harmful substances called free radicals, which can damage muscle tissue and result in inflammation and muscle soreness. Exercising in cities or smoggy areas also increases exposure to free radicals. Antioxidants, including vitamin C and vitamin E, neutralize free radicals before they can damage the body, so antioxidants may aid in exercise recovery. Regular exercise increases the efficiency of the antioxidant defense system, potentially reducing the amount of supplemental antioxidants that might otherwise be needed for protection. However, at least theoretically, supplements of antioxidant vitamins may be beneficial for older or untrained people or athletes who are undertaking an especially vigorous training protocol or athletic event. Placebo-controlled research, some of it double-blind, has shown that taking 400 to 3,000 mg of vitamin C per day for several days before and after intense exercise may reduce pain and speed up muscle strength recovery. However, taking vitamin C only after such exercise was not effective in another double-blind study. While some research has reported that vitamin E supplementation in the amount of 800 to 1,200 IU per day reduces biochemical measures of free radical activity and muscle damage caused by strenuous exercise, several studies have not found such benefits, and no research has investigated the effect of vitamin E on performance-related measures of strenuous exercise recovery. A combination of 90 mg per day of coenzyme Q10 and a very small amount of vitamin E did not produce any protective effects for marathon runners in one double-blind trial, while in another double-blind trial a combination of 50 mg per day of zinc and 3 mg per day of copper significantly reduced evidence of post-exercise free radical activity.
In most well-controlled studies, exercise performance has not been shown to improve following supplementation with vitamin C, unless a deficiency exists, as might occur in athletes with unhealthy or irrational eating patterns. Similarly, vitamin E has not benefited exercise performance, except possibly at high altitudes.
Alkalinizing agents
The use of alkalinizing agents, such as sodium bicarbonate, sodium citrate, and phosphate salts (potassium phosphate, sodium acid phosphate, and tribasic sodium phosphate) to enhance athletic performance is designed to neutralize the acids produced during exercise that may interfere with energy production or muscle contraction. Some double-blind studies, though not all, have found that sodium bicarbonate or sodium citrate typically improves exercise performance for events lasting either 1 to10 minutes or 30 to 60 minutes. The amounts used are 115 to 180 mg of sodium bicarbonate or 135 to 225 mg of sodium citrate per pound of body weight. These amounts are dissolved in at least two cups of fluid and are taken either as a single ingestion at least one hour before exercise or divided into smaller amounts and taken over several hours before exercise. Performance during periods of less than one minute or between 10 and 30 minutes is not improved by taking alkalinizing agents. Sodium citrate may be preferable to sodium bicarbonate because it causes less gastrointestinal upset. Another alkalinizing agent, phosphate salts, has been investigated primarily as an endurance performance enhancer, with very inconsistent results.
DHEA
Dehydroepiandrosterone (DHEA) is a hormone produced by the adrenal glands that is used by the body to make the male sex hormone testosterone. In one double-blind trial, 100 mg per day of DHEA was effective for improving strength in older men, but 50 mg per day was ineffective in a similar study of elderly men and women. DHEA has not been effective for women or younger men in other studies.
Electrolytes
Electrolyte replacement is not as important as water intake in most athletic endeavors. It usually takes several hours of exercise in warm climates before sodium depletion becomes significant and even longer for depletions of potassium, chloride, and magnesium to occur. However, the presence of sodium in fluids will often make it easier to drink as well as to retain more fluid. Athletes participating in several hours of exercise, especially in hot, humid conditions, should use sodium-containing fluids to reduce the risk of performance-diminishing and possibly dangerous declines in blood sodium levels.
Glutamine
The amino acid glutamine appears to play a role in several aspects of human physiology that might benefit athletes, including their muscle function and immune system. Intense exercise lowers blood levels of glutamine, which can remain persistently low with overtraining. Glutamine supplementation raises levels of growth hormone at an intake of 2 grams per day, an effect of interest to some athletes because of the role of growth hormone in stimulating muscle growth, and glutamine, given intravenously, was found to be more effective than other amino acids at helping replenish muscle glycogen after exercise. However, glutamine supplementation (30 mg per 2.2 pounds body weight) has not improved performance of short-term, high-intensity exercise such as weightlifting or sprint cycling by trained athletes, and no studies on endurance performance or muscle growth have been conducted. Although the effects of glutamine supplementation on immune function after exercise have been inconsistent, double-blind trials giving athletes glutamine (5 grams after intense, prolonged exercise, then again two hours later) reported 81% having no subsequent infection compared with 49% in the placebo group.
Phosphatidylserine
In a double-blind study of active young men, supplementation with 750 of soybean-derived phosphatidylserine per day for 10 days increased the time the men could exercise until exhaustion by approximately 25%. Longer studies are needed to determine whether this effect would persist with continued supplementation.
HMB
HMB (beta hydroxy-beta-methylbutyrate) is a metabolite (breakdown product) of leucine, one of the essential branched-chain amino acids. Biochemical and animal research show that HMB has a role in protein synthesis and might, therefore, improve muscle growth and overall body composition when given as a supplement. However, double-blind human research suggests that HMB may only be effective when combined with an exercise program in people who are not already highly trained athletes. Double-blind trials found no effect of 3 to 6 grams per day of HMB on body weight, body fat, or overall body composition in weight-training football players or other trained athletes. However, one double-blind study found that 3 grams per day of HMB increased the amount of body fat lost by 70-year old adults who were participating in a strength-training program for the first time. A double-blind study of young men with no strength-training experience reported greater improvements in muscle mass (but not in percentage body fat) when HMB was used in the amount of 17 mg per pound of body weight per day. However, another group of men in the same study given twice as much HMB did not experience any changes in body composition.
Inosine
Inosine is a nucleic acid derivative that appears in exercising muscle tissue. Its role in various cellular functions has led to suggestions that it may have ergogenic effects. However, three controlled studies demonstrated no beneficial effects on performance and suggested that inosine may impair some aspects of exercise performance. Therefore, use of inosine is discouraged.
Iron
Iron is important for an athlete because it is a component of hemoglobin, which transports oxygen to muscle cells. Some athletes, especially women, do not get enough iron in their diet. In addition, for reasons that are unclear, endurance athletes, such as marathon runners, frequently have low body-iron levels. However, anemia in athletes is often not due to iron deficiency and may be a normal adaptation to the stress of exercise. Supplementing with iron is usually unwise unless a deficiency has been diagnosed. People who experience undue fatigue (an early warning sign of iron deficiency) should have their iron status evaluated by a doctor. Athletes who are found to be iron deficient by a physician are typically given 100 mg per day until blood tests indicate they are no longer deficient. Supplementing iron-deficient athletes with 100 to 200 mg per day of iron increased aerobic exercise performance in some, though not all, double-blind studies. A recent double-blind trial found that iron-deficient women who took 20 mg per day of iron for six weeks were able to perform knee strength exercises for a longer time without muscle fatigue compared with those taking a placebo.
Protein
Certain amino acids, the building blocks for protein, might be ergogenic aids as discussed in this article. However, while athletes have an increased need for protein compared with non-exercising adults, the maximum amount of protein suggested by many researchers—0.75 grams per pound of body weight per day—is already in the diet of most athletes as long as they are not restricting calories. Preliminary studies have suggested that supplementing with combinations of amino acids, typically along with carbohydrate, immediately after exercise increases muscle protein synthesis. However, long-term controlled trials in young adult men, older men, and women have found no benefits in strength gains from supplementing with amino acids after weight training exercise.
In one preliminary study, elderly men participating in a 12-week strength training program took a liquid supplement containing 10 grams of protein (part of which was soy protein), 7 grams of carbohydrate, and 3 grams of fat either immediately following exercise or two hours later. Men taking the supplement immediately following exercise experienced significantly greater gains in muscle growth and lean body mass than those supplementing two hours later, but strength gains were no different between the two groups. A controlled study of female gymnasts found that adding 0.45 grams of soy protein (0.45 grams per pound of body weight per day) to a diet that was adequate in protein during a four-month training program did not improve lean body mass compared with a placebo. No research has compared different sources of protein to see whether one source, such as soy protein, has a better or more consistent effect on exercise recovery or the results of strength training.
Animal studies suggest that whey protein can increase gains in lean body mass resulting from exercise. A controlled trial found that six weeks of strength training while taking 1.2 grams of whey protein per 2.2 of pounds body weight per day resulted in greater gains in lean body mass, but improved only one out of four strength tests. Another controlled study found that people taking 20 grams per day of whey protein for three months performed better on a test of short-term intense cycling exercise than people taking a similar amount of milk protein (casein). However, a double-blind trial found that men taking 1.5 grams per 2.2 lbs of body weight per day of predigested whey protein for 12 weeks along with a strength training exercise program gained only half as much lean body mass and had significantly smaller increases in strength compared with men using a similar amount of predigested casein along with strength training. A controlled study of HIV-infected women found that adding whey protein to strength training exercise was no more effective than exercise alone for increasing strength or improving body composition.
Pyruvate
One group of researchers in two small, controlled trials has reported that 100 grams of a combination of dihydroxyacetone and pyruvate enhanced the endurance of certain muscles in untrained men. Three controlled studies of untrained individuals using a combination of 6 to 10 grams per day of pyruvate and an exercise program reported greater effects on weight loss and body fat compared with those taking a placebo with the exercise program. However, in a study of healthy untrained women undergoing an exercise program, supplementing with 5 grams of pyruvate twice a day had no effect on exercise performance.Studies of pyruvate supplementation on exercise performance in trained athletes have also failed to demonstrate any beneficial effect. Seven grams per day did not improve aerobic exercise performance in cyclists,and an average of 15 grams per day did not improve anaerobic performance or body composition in football players.More recently, evidence has appeared casting doubt on the ability of high levels (an average exceeding 15 grams per day depending upon body weight) of pyruvate to improve exercise capacity in a weight-lifting study.
Quercetin
In a double-blind study of trained athletes, the incidence of upper respiratory tract infections following a 3-day period of intensive exercise was significantly lower in people who took quercetin than in those who received a placebo (5% versus 45%). The amount of quercetin used was 500 mg twice a day, beginning 3 weeks before, and continuing for 2 weeks after, the intensive exercise.
Zinc
Exercise increases zinc losses from the human body, and severe zinc deficiency can compromise muscle function. Athletes who do not eat an optimal diet, especially those who are trying to control their weight or use fad diets while exercising strenuously, may become deficient in zinc to the extent that performance or health is compromised. One double-blind trial in women found that 135 mg per day of zinc for two weeks improved one measure of muscle strength. Whether these women were zinc deficient was not determined in this study. A double-blind study of male athletes with low blood levels of zinc found that 20 mg per day of zinc improved the flexibility of the red blood cells during exercise, which could benefit blood flow to the muscles. No other studies of the effects of zinc supplementation in exercising people have been done. A safe amount of zinc for long-term use is 20 to 40 mg per day along with 1 to 2 mg of copper. Higher amounts should be taken only under the supervision of a doctor.
AKG
AKG (alpha-ketoglutarate) is used by cells during growth and in healing from injuries and other wounds, and is especially important in the healing of muscle tissue. A controlled study found that intravenous AKG prevented a decline in protein synthesis in the muscles of patients recovering from surgery. For these reasons, it has been speculated that oral AKG supplements might help improve strength or muscle-mass gains by weight lifters, but no research has been done to test this theory.
Arginine/Ornithine
At very high intakes (approximately 250 mg per 2.2 pounds of body weight), the amino acid arginine has increased growth hormone levels, an effect that has interested body builders due to the role of growth hormone in stimulating muscle growth. However, at lower amounts recommended by some manufacturers (5 grams taken 30 minutes before exercise), arginine failed to increase growth hormone release and may even have impaired the release of growth hormone in younger adults. Large quantities (170 mg per 2.2 pounds of body weight per day) of a related amino acid, ornithine, have also raised growth hormone levels in some athletes. High amounts of arginine or ornithine do not appear to raise levels of insulin, another anabolic (bodybuilding) hormone. More modest amounts of a combination of these amino acids have not had measurable effects on any anabolic hormone levels during exercise.
Nonetheless, double-blind trials conducted by one group of researchers, combining weight training with either arginine and ornithine (500 mg of each, twice per day, five times per week) or placebo, found the amino-acid combination produced decreases in body fat, resulted in higher total strength and lean body mass, and reduced evidence of tissue breakdown after only five weeks.
Aspartic acid
Aspartic acid is a non-essential amino acid that participates in many biochemical reactions relating to energy and protein. Preliminary, though conflicting, animal and human research suggested a role for aspartic acid (in the form of potassium and magnesium aspartate) in reducing fatigue during exercise. However, most studies have found aspartic acid useless in improving either athletic performance or the body’s response to exercise.
B-complex vitamins
The B-complex vitamins are important for athletes, because they are needed to produce energy from carbohydrates. Exercisers may have slightly increased requirements for some of the B vitamins, including vitamin B2, vitamin B6, and vitamin B5 (pantothenic acid; athletic performance can suffer if these slightly increased needs are not met. However, most athletes obtain enough B vitamins from their diet without supplementation, and supplementation studies have found no positive effect on performance measures for vitamin B2, vitamin B3 (niacin), or vitamin B6. On the contrary, large amounts of niacin have been shown to impair endurance performance.
Beta-sitosterol
Beta-sitosterol, (BSS) a natural sterol found in many plants, has been shown in a double-blind trial to improve immune function in marathon runners when combined with a related substance called B-sitosterol glucoside (BSSG). This implies that beta-sitosterol might reduce infections in athletes who engage in intensive exercise, though studies are still needed to prove this. The usual amount of this combination used in research is 20 mg of BSS and 200 mcg of BSSG three times per day.
Branched-chain amino acids
Some research has shown that supplemental branched-chain amino acids (BCAA) (typically 10 to 20 grams per day) do not result in meaningful changes in body composition, nor do they improve exercise performance or enhance the effects of physical training.However, BCAA supplementation may be useful in special situations, such as preventing muscle loss at high altitudes and prolonging endurance performance in the heat. One controlled study gave triathletes 6 grams per day of BCAA for one month before a competition, then 3 grams per day from the day of competition until a week following. Compared with a placebo, BCAA restored depleted glutamine stores and immune factors that occur in elite athletes, and led to a reported one-third fewer symptoms of infection during the period of supplementation. Studies by one group of researchers suggest that BCAA supplementation may also improve exercise-induced declines in some aspects of mental functioning.
Bromelain
Bromelain is effective for shortening the healing time of such injuries as sprains and strains. Typically, two to four tablets or capsules are taken several times per day. Other uses of bromelain for sports and fitness have not been studied.
Caffeine
Caffeine is present in many popular beverages and appears to have an effect on fat utilization. Caffeine does not benefit short-term, high-intensity exercise, according to most, but not all, studies. However, controlled research, much of it double-blind, has shown that endurance performance lasting at least 30 minutes does appear to be enhanced by caffeine in many athletes. Inconsistency in reported effectiveness of caffeine in some trials can be explained by differences in caffeine sensitivity among athletes, variable effects of caffeine on different forms of exercise and under different environmental conditions, and effects of other dietary components on the response to caffeine. Effective amounts of caffeine appear to range from 1.4 to 2.7 mg per pound of body weight, taken one hour before exercise. While this amount of caffeine could be obtained in 1 to 3 cups of brewed coffee, most research has used caffeine supplements in capsules, and a recent study found caffeine was not effective when taken as coffee. Caffeine consumption is banned by the International Olympic Committee at levels that produce urinary concentrations of 12 mg per milliliter or more. These levels would require ingestion of considerably more than 2.5 mg per pound of body weight, or several cups of coffee, over a short period of time.
Calcium
Calcium is important for achieving and maintaining optimum bone density. Some athletes, especially women with low body weight and/or amenorrhea, are at risk for serious bone loss and fractures. Contributing to this risk are the diets of these athletes, which are frequently deficient in calcium. All athletes should try to achieve the recommended intakes of calcium, which are 1,300 mg per day for teenagers and 1,000 mg per day for adults. Other uses of calcium for sports and fitness, including prevention or relief of sports-related muscle cramps, have not been studied.
Chromium
Chromium, primarily in a form called chromium picolinate, has been studied for its potential role in altering body composition. Preliminary research in animals and humans suggested that chromium picolinate might increase fat loss and lean muscle tissue gain when used with a weight-training program. However, most studies have found little to no effect of chromium on body composition or strength. One group of researchers has reported significant reductions in body fat in double-blind trials using 200 to 400 mcg per day of chromium for six to twelve weeks in middle-aged adults, but the methods used in these studies have been criticized.
Chondroitin sulfate
Chondroitin sulfate, 800 to 1,200 mg per day, is effective for reducing joint pain caused by osteoarthritis. Other uses of chondroitin sulfate for sports and fitness, including prevention of joint pain or treatment of sports injuries, have not been studied.
CLA
Conjugated linoleic acid (CLA) is a slightly altered form of the essential fatty acid linoleic acid. Animal research suggests an effect of CLA supplementation on reducing body fat. Controlled human research has reported that 5.6 to 7.2 grams per day of CLA produces only non-significant gains in muscle size and strength in experienced and inexperienced weight-training men. A double-blind study of a group of trained men and women reported reduced body fat in the upper arm after 12 weeks of supplementation with 1.8 grams per day of CLA. Further research using more accurate techniques for measuring body composition is needed to confirm these findings.
Coenzyme Q10
Strenuous physical activity lowers blood levels of coenzyme Q10 (CoQ10). However, while some studies have shown that CoQ10 improves the way the healthy body responds to exercise, other studies have found no improvement. A few studies, using at least four weeks of CoQ10 supplementation at 60 to 100 mg per day, have reported improvements in measures of work capacity ranging from 3 to 29% in sedentary people and from 4 to 32% in trained athletes.However, recent double-blind and/or placebo-controlled trials in trained athletes, using performance measures such as time to exhaustion and total performance, have found either no significant improvement or significantly poorer results in those taking CoQ10.
Gamma oryzanol
Gamma oryzanol is a mixture of sterols and ferulic acid esters. Despite claims that gamma oryzanol or its components increase testosterone levels, stimulate the release of endorphins, and promote the growth of lean muscle tissue, research has provided little support for these claims and has also shown gamma-oryzanol to be poorly absorbed.A recent nine-week, double-blind trial of 500 mg per day of gamma-oryzanol in weight lifters found no benefit compared with placebo in strength performance gains or circulating anabolic hormones.However, a small, double-blind trial using 30 mg per day of ferulic acid for eight weeks in trained weight lifters did find significantly more weight gain (though lean body mass was not measured) and increased strength in one of three measures compared with placebo.
Glucosamine
Glucosamine sulfate, 1,500 mg per day, is effective for reducing joint pain caused by osteoarthritis according to most studies. Whether other forms of glucosamine, such as glucosamine hydrochloride, are as effective for joint pain as glucosamine sulfate is unclear at this time, but studies have found some benefits from the use of the hydrochloride form.Other uses of glucosamine for sports and fitness, including prevention of joint pain or treatment of sports injuries, have not been studied.
L-carnitine
L-carnitine, which is normally manufactured by the human body, has been popular as a potential ergogenic aid (i.e., having the ability to increase work capacity), because of its role in the conversion of fat to energy.However, while some studies have found that L-carnitine improves certain measures of muscle physiology, research on the effects of 2 to 4 grams of L-carnitine per day on performance have produced inconsistent results.L-carnitine may be effective in certain intense exercise activities leading to exhaustion,but recent studies have reported that L-carnitine supplementation does not benefit non-exhaustive or even marathon-level endurance exercise,anaerobic performance,or lean body mass in weight lifters.316
Magnesium
Magnesium deficiency can reduce exercise performance and contribute to muscle cramps, but sub-optimal intake does not appear to be a problem among most groups of athletes.Controlled trials suggest that magnesium supplementation might improve some aspects of physiology important to sports performance in some athletes, but controlled and double-blind trials focusing on performance benefits of 212 to 500 mg per day of magnesium have been inconsistent. It is possible that magnesium supplementation benefits only those who are deficient or who are not highly trained athletes.
Medium chain triglycerides
Medium chain triglycerides (MCT) contain a class of fatty acids found only in very small amounts in the diet; they are more rapidly absorbed and burned as energy than are other fats. For this reason, athletes have been interested in their use, especially during prolonged endurance exercise. However, no effect on carbohydrate sparing or endurance exercise performance has been shown with moderate amounts of MCT (30 to 45 grams over two to three hours). Controlled trials using very large amounts of MCT (approximately 85 grams over two hours) have resulted in both increased and decreased performance, while a double-blind trial found that 60 grams per day of MCT for two weeks had no effect on endurance performance. A controlled study found increased performance when MCTs were added to a 10% carbohydrate solution, but another study found no advantage of adding MCT, and a third trial actually reported decreased performance with this combination, probably due to gastrointestinal distress, in athletes using MCTs.
Octacosanol
Wheat germ oil, which contains a waxy substance known as octacosanol, has been investigated as an ergogenic agent. Preliminary studies have suggested that octacosanol improves endurance, reaction time, and other measures of exercise capacity. In another preliminary trial, supplementation with 1 mg per day of octacosanol for eight weeks improved grip strength and visual reaction time, but it had no effect on chest strength, auditory reaction time, or endurance.
Ornithine alpha-ketoglutarate
Ornithine alpha-ketoglutarate (OKG) is formed from the amino acids ornithine and glutamine and is believed to facilitate muscle growth by enhancing the body’s release of anabolic hormones. While this effect has been found in studies on hospitalized patients and elderly people, no studies on muscle growth in athletes using OKG have been published.
Methoxyisoflavone
Methoxyisoflavone is a member of the family flavonoids (isoflavones). In a U.S. Patent, the developers of this substance claim, based on preliminary animal research, that it possesses anabolic (muscle-building and bone-building) effects without the side effects seen with either androgenic (male) hormones or estrogenic (female) hormones. A preliminary controlled trial found that strength-training athletes who took 800 mg per day of methoxyisoflavone for eight weeks experienced a significantly greater reduction in percentage body fat than those who took a placebo. Double-blind research is needed to confirm these findings. The U.S. patent also claims methoxyisoflavone reduces appetite and lowers blood cholesterol levels. Whether this claim is true has not yet been demonstrated in published scientific research.
Ribose
Ribose is a type of sugar used by the body to make the energy-containing substance adenosine triphosphate (ATP). Intense exercise depletes muscle cells of ATP as well as the ATP precursors made from ribose, though these deficits are typically replaced within minutes.346 Unpublished reports suggested that ribose supplementation might increase power during short, intense bouts of exercise. However, in a double-blind study, exercisers took four grams of ribose four times per day during a six-day strength-training regimen, and no effects on muscle power or ATP recovery in exercised muscles were found. In two other controlled studies, either 10 grams of ribose per day for five days or 8 grams every 12 hours for 36 hours resulted in only minor improvements in some measures of performance during repetitive sprint cycling.
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful
Ginseng
Extensive but often poorly designed studies have been conducted on the use of Asian ginseng (Panax ginseng) to improve athletic performance. While some early controlled studies suggested there might be benefits, several recent double-blind trials have found no significant effects of Asian ginseng on endurance exercise. In many studies, it is possible that ginseng was used in insufficient amounts or for an inadequate length of time; a more effective regimen for enhancing endurance performance may be 2 grams of powdered root per day or 200 to 400 mg per day of an extract standardized for 4% ginsenosides, taken for eight to twelve weeks. Short-term intense exercise has also not been helped by Asian ginseng according to double-blind trials, but one controlled study reported increased pectoral and quadricep muscle strength in non-exercising men and women after taking 1 gram per day of Asian ginseng for six weeks. An extract of a related plant, American ginseng (Panax quinquefolius), was found ineffective at improving endurance exercise performance in untrained people after one week’s supplementation in a double-blind study.
Eleuthero
Eleuthero (Eleutherococcus senticosus) supplementation may improve athletic performance, according to preliminary Russian research. Other studies have been inconclusive and two recent double-blind studies showed no beneficial effect on endurance performance in trained men. Eleuthero strengthens the immune system and thus might reduce the risk of post-exercise infection. Although some doctors suggest taking 1 to 4 ml (0.2 to 0.8 tsp) of fluid extract of eleuthero three times per day, evidence supporting the use of this herb to enhance athletic performance remains weak.
Rhodiola
In a double-blind trial, healthy volunteers received 200 mg of an extract of Rhodiola rosea (standardized to contain 3% rosavin plus 1% salidroside) or a placebo one hour prior to an endurance-exercise test. Compared with placebo, rhodiola significantly increased endurance, as measured by the time it took to become exhausted. However, after daily use of rhodiola for four weeks, the herb no longer enhanced short-term endurance. Consequently, if rhodiola is being considered as an exercise aid, it should be used only occasionally.
Arnica
Arnica-containing ointments are recommended by many practitioners for the treatment of sprains and strains and other traumatic injuries. Homeopathic arnica tablets are also used by some practitioners for similar conditions. One uncontrolled trial showed that arnica gel applied twice daily reduced symptoms of osteoarthritis of the knee and a double-blind study reported that a combination of topical arnica ointment and oral homeopathic arnica tablets reduced pain in people recovering from hand surgery. No other studies of topical arnica have been done, but several studies of homeopathic arnica have found it ineffective for treating muscle and joint pain.
Cayenne (topical capsaicin)
Capsaicin ointment, applied four times per day over painful joints in the upper or lower limbs, reduces pain caused by osteoarthritis, and a plaster containing capsaicin applied to the low back for several hours per day provided relief from chronic low back pain in one study. Other uses of cayenne or capsaicin for sports and fitness have not been studied.
Eucalyptus
Eucalyptus-based rubs have been found to warm muscles in athletes. This suggests that eucalyptus may help relieve minor muscle soreness when applied topically, though studies are needed to confirm this possibility.
Guaraná and kola
Some athletes take guaraná during their training; however, there is no scientific research to support this use. Guaraná contains caffeine. Another caffeine-containing herb sometimes used during training is kola nut.
Tribulus
Extracts of Tribulus terrestris (puncture vine) have been reported in preliminary studies to affect anabolic hormones in men. However, a double-blind trial found no effect of 1.5 mg per day of tribulus per pound of body weight on improving body composition or strength performance results from an eight-week strength training program.
Yohimbine
The ability of yohimbine, a chemical found in yohimbe bark, to stimulate the nervous system, promote the release of fat from fat cells, and affect the cardiovascular system has led to claims that yohimbe might help athletic performance or improve body composition. However, a double-blind study of men who were not dieting reported no effect of up to 43 mg per day of yohimbine on weight or body composition after six months. No research has tested yohimbe herb for effects on body composition, and no human research has investigated the ability of yohimbine or yohimbe to affect athletic performance. Other studies have determined that a safe daily amount of yohimbine is 15 to 30 mg. However, people with kidney disorders should not take yohimbe, and side effects of nausea, dizziness, or nervousness may occur that necessitate reducing or stopping yohimbe supplementation.
Are there any side effects or interactions?
Refer to the individual herb for information about any side effects or interactions.
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