Supplements: What Works and What Does Not Work, Part 2

The Best Alternative Medicine
by Kenneth R. Pelletier

(Page 5 of 5)

Overall, SOD research is intriguing, but there is no form of SOD available to the public that will raise levels of SOD in the cells. It is much too early to recommend any use of SOD as an oral supplement, although it may have applications in specific medical treatments.

L-carnitine. L-carnitine is a substance that is essential for good health and for the regulation of fat oxidation in the body. Fatty acids are the main sources for energy production in the heart and the skeletal muscles, and these organs are especially vulnerable to L-carnitine deficiency. Symptoms of deficiency include muscle weakness, severe confusion, and angina.

Certain groups of people are at particular risk for L-carnitine deficiency, including kidney failure patients on hemodialysis, patients with liver failure, and patients receiving total parenteral (IV) nutrition. Some healthy individuals also have increased needs for dietary L-carnitine, including strict vegetarians, premature infants, pregnant women, and nursing mothers.

Dietary sources of L-carnitine are red meat, especially lamb and beef, and dairy products. There is little or no L-carnitine in vegetables, fruits, and cereals. How much L-carnitine is needed in the diet for optimal health is not known.

L-carnitine supplements are available in both the DL form and the L form. Only the L-carnitine form should be used, since the DL form has been shown to cause a muscle weakness syndrome in some individuals. Large doses of L-carnitine may cause diarrhea. Supplements may vary in purity.

Among the claims made for L-carnitine are that it increases blood flow and enhances energy production during exercise. Athletes and bodybuilders often use it.

• Cardiovascular protection. A number of well-designed clinical studies have shown that L-carnitine supplementation does have protective effects with heart patients. According to Bartels, Singh, and others, it appears to reduce angina and ischemia, and can significantly improve exercise duration. In patients with suspected myocardial infarction, it reduces infarction size, angina, cardiac death, and nonfatal infarction.

• Exercise performance. Evidence for improved exercise performance among athletes is not as convincing. In a 1997 review by Dr. Pamela Peeke, researchers found no controlled studies indicating improved physical performance in athletes. Two studies, one by Otto in 1987 and the other by Kasper in 1994, found that it did not produce an improvement for competitive runners.

• Lipid metabolism. Clinical studies are inconclusive on whether carnitine supplementation enhances the oxidation of fatty acids. A 1993 study by Natali found that L-carnitine did not influence lipid metabolism at rest, but did during exercise. However, two other studies found no effect, as reported by Decombaz in 1993 and Oyono-Enguelle in 1988.

While L-carnitine supplementation may help with deficiency states, there is little evidence that it helps healthy people.

Creatine. Creatine is an energy-producing substance that works as an energy storehouse and recharges the energy molecule adenosine triphosphate. Creatine is often used by bodybuilders and other athletes in high-intensity, explosive sports.

Dietary sources are meat and fish, though cooking can destroy it. Vegetarians are not able to get a presynthesized, concentrated form of creatine from their diet.

• Supplementation increases muscle creatine. In a 1995 study by Gordon of congestive heart failure patients, researchers found that creatine supplements did increase creatine phosphate in skeletal muscle, but only in patients whose total creatine level was relatively low to begin with. In this group, supplementation significantly increased strength and endurance.

• Sports performance. Creatine supplementation will not improve performance in endurance types of exercise, such as long-distance running, but does significantly improve performance in short-duration, high-intensity exercise. In a 1994 study of athletes by Birch in England, cellular energy production was higher and more efficient. A 1993 study by Dr. Paul Greenhaff found that creatine supplementation significantly increased performance of subjects doing maximal knee extensor exercise. According to Burke in 1996, a group of elite swimmers who received creatine supplementation showed no significant improvement. From a 1996 study of runners by Redondo, no statistically significant effect on sprint velocity was found.

Although creatine has no well-documented negative effects, supplementation does not seem necessary for daily maintenance of optimum health. However, it may help for specific power sports and bodybuilding. Athletes considering creatine supplementation for such purposes should consult with a sports medicine specialist.

DHEA. DHEA stands for dehydroepiandrosterone, a hormone that was first discovered in 1934. Its significance has been somewhat of a mystery ever since. Claims made for DHEA include that it prevents or slows the aging process, promotes weight loss, prevents or alleviates Alzheimer's disease, and combats AIDS, lupus, and some cancers. More than ten thousand scientific papers have been written about DHEA, and two international conferences have been held on DHEA research.

DHEA is the most abundant steroid hormone in our bodies. It is mainly produced in the adrenal glands, and also in the brain and skin. In the body, DHEA is converted in both men and women into estrogen, testosterone, and other steroid hormones. Production of DHEA peaks at about age thirty, and then gradually declines, reaching about 5 to 15 percent of the peak level at about age sixty. DHEA levels also drop during illness.

Research has shown that low DHEA levels in the blood are associated with heart disease, breast cancer, and a decline in immune competence. Most of the information about DHEA at present comes from animal studies, test tube experiments, and human population studies. Human clinical research is currently limited, with no long-term trials. It is not known at this point whether the effects of DHEA are due to the hormone itself or to the sex hormones and other steroids that the body produces, nor is it known which organs DHEA affects.

DHEA was found in one study to produce liver cancer in fourteen out of sixteen rats. While this does not necessarily mean that it would produce cancer in humans, if such a response were to occur in human research, DHEA would probably be banned by the FDA. Other studies have shown that DHEA supplementation can lead to increased insulin resistance, unwanted hair growth, and a drop in levels of "good" HDL. It must be remembered that DHEA is a hormone, and replacing any hormone that declines normally with aging must be carefully researched.

• Aging. Human studies on the effect of DHEA replacement on the aging process look promising, but it is too early to draw definite conclusions. In a 1994 study by Morales at the University of California at San Diego, people ages forty to seventy who took DHEA reported a substantial increase in physical and psychological well-being. However, HDL levels declined slightly in women.

• Weight control. Clinical research by Dr. William Regelson in 1996, done only on animals, showed that DHEA promoted weight loss in overweight animals even when they ate their usual diet. A 1991 human population study by Dr. Elizabeth Barrett-Connor found that lower DHEA levels in the blood were associated with increased body mass and impaired glucose tolerance.

• Menopausal symptoms. DHEA may help replace hormones in postmenopausal women, and thus protect against cancer, osteoporosis, and cardiac disease. Research is still preliminary, but in Europe, DHEA products are being marketed for menopause-related depression, and are being used in conjunction with estrogen to treat hot flashes and other menopausal symptoms. In a Canadian study by Dr. Pierre Diamond of twenty postmenopausal women, DHEA yielded reductions in blood insulin and glucose levels. Weight remained the same, but there was an improvement in the body muscle to-fat ratio, an increase in bone density, a drop in blood cholesterol, and an improvement in vaginal atrophy and secretions.

  Studies by Casson in 1993 and 1995 also suggest that DHEA may help postmenopausal women, affording protection against heart disease by reducing blood lipid levels.

• Heart disease. DHEA may help to protect against heart disease in people besides postmenopausal women. A 1995 study by Herrington, reported at the New York Academy of Sciences, found significantly lower blood levels of DHEA in men who had blocked arteries. Another study reported at the conference showed DHEA supplementation reduced platelet aggregation, or the tendency of blood cells to stick together. Excessive platelet aggregation is another risk factor for cardiovascular disease.

• Immune problems. Researchers have reported that DHEA activated immune system functioning. In a 1993 study by Casson, 25 mg daily improved immune regulating response in postmenopausal women.

  There is some suggestion that autoimmune disorders also respond. In a 1995 study by Dr. Ronald van Vollenhoven of the Stanford University School of Medicine, twenty-five female lupus patients who received 200 mg of DHEA showed improvement in their symptoms, had more energy, and were able to reduce their prednisone dosage.

In conclusion, while popular literature enthusiastically endorses the use of DHEA, it is too early to recommend routine supplementation. Anyone considering DHEA supplementation should have their DHEA levels checked to make sure that they are low. Serum levels of steroids should be monitored medically while taking DHEA supplements. DHEA is not fat soluble, so any fat in a meal will block absorption of the supplement. Letting DHEA absorb under the tongue is one way to bypass the intestinal tract, but some people object to the taste. Since blood levels of DHEA are highest in the morning, supplemental DHEA should be taken in the morning, to follow the body's natural rhythm.

Because DHEA is converted into steroid hormones, it is not known what its impact might be on cancers that are sensitive to hormones. There is some evidence that DHEA exacerbates breast cancer, and possibly prostate cancer. If any kind of cancer is present, DHEA supplementation should not be undertaken without medical approval.

Melatonin. Melatonin is one of the new "miracle" hormones being widely promoted today. It is produced by the pineal gland, which begins to shrink at about age twenty, with an accompanying steady decrease in melatonin production of about 1 percent a year. Calcification of the pineal gland occurs in many people over sixty.

Melatonin helps regulate the body's sleep cycle. Light suppresses melatonin production, and dark stimulates it, inducing drowsiness. Older people with sleep problems often have low levels of melatonin.

Melatonin is popular as an aid for sleep, jet lag, and insomnia caused by working at night. It has also been claimed that melatonin is a powerful antioxidant that helps with aging and immunity, and reduces the risk of cancer and heart disease.

Research on melatonin is still in the preliminary stages, with most of the work having been done in animal studies or small studies of human subjects, often not completely controlled.

• Sleep disorders. A number of small studies indicate that melatonin helps people sleep and thus improves daytime alertness and well-being. Researchers usually give 2 mg at bedtime for sleep, but some individuals need as little as 0.5 mg. Other people, however, are stimulated by melatonin, or have nightmares or hangovers. Also, a 1997 paper by the National Sleep Foundation claimed it may harm the reproductive system.

• Phase shift regulation. Some small studies of night-shift workers have shown that melatonin helps people adjust to phase shifts. However, in studies by Folkard and Dawson, the use of bright light was generally more effective than melatonin in producing adaptation to changed sleep time. Studies of phase shift regulation remain inconclusive, since the groups studied have been quite small, and since the results were not always in favor of melatonin.

• Jet lag. Larger studies of airline crews and travelers found that melatonin helped adjustment to jet lag. Optimal timing of melatonin doses to prevent jet lag was different in different studies. In a 1993 study by Petrie, 5 mg doses were begun on arrival at the destination and continued for five days. In an earlier study by Petrie, jet lag was reduced by taking 5 mg of melatonin three days before the flight, during the flight, and once a day for three days after arrival.

• Cancer treatment. In a 1996 Italian study by Dr. Paoli Lissoni, thirty patients with brain tumors received either radiation therapy alone or radiation plus melatonin. Survival was higher in patients receiving the melatonin. Also, side effects of cancer immunotherapy were reduced with melatonin. From another study of thirty patients with gastrointestinal cancer, immune functioning after surgery was improved by melatonin and immunotherapy.

• Protection of tissues. Melatonin's protective effect against potentially harmful drugs and radiation may be due in part to its antioxidant properties. It is a potent scavenger of the hydroxyl radical, perhaps the most active of all the free radicals. In this capacity, melatonin is said to help retard the aging process. It is also believed to stimulate the production of glutathione peroxidase, which plays an important role in neutralizing free radicals. Also, it has been hypothesized by Reiter in 1995 that the waning of melatonin levels acts as a switch for programmed aging of the cells.

In the final analysis, the research on melatonin remains inconclusive. In addition, there are some warnings and contraindications that need to be observed. Some studies suggest that melatonin can deepen or induce depression and exacerbate allergies. Melatonin counteracts the effects of cortisone, so patients taking cortisone should avoid it. Also, some preliminary data suggest that melatonin may cause constriction of blood vessels, may inhibit fertility, may suppress the male sexual drive, and may produce hypothermia and retinal damage. As with any powerful hormone, melatonin should not be taken by pregnant women.

Another concern is the purity of the product. Quality of this hormone is not currently regulated by the FDA, and some products are inferior.

While melatonin does seem to have exciting potential, it is much too early to recommend taking such a powerful substance as an over-the-counter supplement. Anyone considering taking it for sleep or jet lag should receive medical clearance.

Testosterone. Testosterone is the primary male sex hormone. It is produced in both men and women, and is responsible for promoting sexual desire in both sexes. Levels of testosterone decline with aging, though the decline is not as sharp and dramatic as the decline of estrogen in women at menopause. Impotence in older men is due in some cases to declining testosterone levels. If testosterone deficiencies are found in men with impotence, injections of testosterone can sometimes help to overcome the problem.

When testosterone was first identified in the 1930s, it was hailed as a miracle substance that could slow aging. It was used to restore libido and mental and physical energy among older adults. When it was discovered that large doses could promote prostate cancer, its use declined. Currently, though, it is being used increasingly to treat aging men with slight reductions in testosterone levels.

Some women, too, are receiving testosterone replacement therapy after menopause. Women normally produce small amounts of testosterone, just as men produce small quantities of estrogen. In younger women, testosterone levels rise just before ovulation, producing a surge in libido. By age forty, testosterone levels in women have declined to only half their value at age twenty, partly owing to the decline in DHEA, the hormone used by the body to make testosterone.

• Strength and muscle mass. Bodybuilders and other athletes, both men and women, have been using testosterone and other anabolic, or muscle building, steroids to build muscle and lean body mass. Unfortunately, the high doses of steroids used by athletes have been linked to heart disease, stroke, cardiomyopathy, and possibly cancer. Other adverse effects include liver toxicity, decreases in plasma testosterone, atrophy of the testes, prostate enlargement, impotence, decreased sperm count, breast enlargement in men, increased injury of muscles and tendons, increased serum cholesterol, and decreased HDL. Psychological side effects can include euphoria, aggressiveness, irritability, nervous tension, changes in libido, mania, and psychosis. Female athletes have less-well-documented side effects, including irreversible lowering of the voice, increased libido, menstrual disturbances, aggressiveness, acne, increased body hair, and clitoral enlargement.

• Arthritis. Testosterone has been studied as a treatment for rheumatoid arthritis, with equivocal results. In a 1996 study by Booji, it caused improvement in rheumatoid arthritis symptoms. However, in a 1996 study by Hall, there was no significant effect on the disease.

Testosterone is not available as a dietary supplement. It is available only by prescription and is relatively expensive, at fifty to one hundred dollars a month. Besides injections, testosterone is now available in a new patch that can be worn on any part of the body, making it easier to use. It was formerly available in the United States only by injection, or by a patch worn on the scrotum. In Europe, testosterone is available in pills, but these have not been approved for use in the United States.

To summarize, testosterone is appropriate for severe testosterone deficiency, and for older men, and perhaps women, whose low testosterone levels have caused loss of libido. However, even in small doses, it can encourage prostate tumors. Testosterone also increases the risk of stroke.

Testosterone is a very powerful hormone that can have very serious side effects, and should only be used under appropriate medical supervision.

Creating a Personalized Nutritional Program

Biochemical individuality means that we all have slightly different dietary needs, based on our genetic endowment, exercise level, metabolic function, state of health, geographic location, and other factors. To sort out what this means in terms of diet and supplement choices, professional help is available from a number of disciplines.

Before making radical changes in your diet or lifestyle, remember that in order to maintain new health behaviors, these changes need to be supported by many sources, such as family and friends. Enlist the cooperation and encouragement of family and friends, and reinforce your decisions by reading material that underscores the benefits of the changes you are planning. If you are making significant changes in your diet, such as adopting a more plant-based or vegetarian diet, make every effort to ensure that your new diet is appealing to all your senses and includes a variety of colors, tastes, and aromas. This not only whets the appetite, it also helps to ensure that your diet will provide all the protective nutrients your body requires. Even a weight-loss regimen need not produce a feeling of deprivation. A slimming diet rich in grains, legumes, fresh fruits, and vegetables can be very satisfying and appealing to the senses.

It is wise to consult with your doctor or nutritionist before undertaking any supplementation beyond the use of antioxidant vitamins such as C, E, the B vitamins, and calcium/magnesium for women who require calcium throughout their lives as one deterrent to osteoporosis. Maintaining a balanced ratio of calcium to magnesium can also be delicate. Trained professionals are able to evaluate whether any medications or health conditions would contraindicate the use of the more controversial substances discussed above.

Many of the more controversial supplements have had intriguing claims made for their anti-aging and longevity properties, and research has begun to document the potential value of some of these substances for restoring and preserving youthful vigor. However, no nutrient, supplement, or magic bullet can take the place of a balanced, well-rounded diet and a lifestyle conducive to optimal health. Regular exercise, social engagement and support, good stress management practices, a feeling of optimism, and a sense of purpose in life are all just as important as any supplements you might take in assuring you a long and healthy life. Positive mental attitude grows out of and reinforces good dietary practices. Each positive lifestyle habit you cultivate magnifies and multiplies itself throughout every aspect of your life. When you know that you have made dietary changes that will be beneficial for you, your feeling of self-worth and empowerment will improve along with your level of physical well-being. Even older adults with chronic diseases have a better prospect for survival and for less troublesome symptoms when they know that they have control over those areas in their lives where they can exercise choice.

Copyright © 2000 by Dr. Kenneth R. Pelletier, Inc.

About the Author

Dr. Kenneth R. Pelletier is a clinical professor of medicine at the University of Maryland and the University of Arizona Schools of Medicine. He is a medical and business advisor to NIH, the World Health Organization (WHO), and major corporations, including American Airlines, Medtronic, Disney, Merck, Ford, Microsoft, Blue Cross, Blue Shield, and United Healthcare. As director of the American Health Association, he is the author of more than two hundred professional papers, and he was previously a clinical professor of medicine at the Stanford University School of Medicine.