|
The Herbal Hype of Dietary Supplements Physicians need to educate themselves about supplements used by the elderly, who are taking them in record numbers. Their names are exotic. Their pitches are enticing. And to the elderly, dietary and nutritional supplements seem like just what the doctor ordered. Some studies have reported the benefits of using certain supplements, but not all doctors are convinced of the safety and effectiveness of most of them, or the validity of the promises. "These people are snake oil salesmen, and what they're selling is magic," said nutritional researcher Victor Herbert, MD, professor of medicine at Mt. Sinai-New York University Health System, New York City. Supplements include vitamins, minerals, amino acids and herbs. Manufacturers promise older people that the remedies will improve digestion, aid sleep, enhance memory, strengthen bones and joints, shrink the prostate, relieve symptoms of menopause and promote "healthier brain function and well-being." The products have mushroomed into a $15-billion-a-year pharmaceutical industry. "A lot of people are still very skeptical and consider [supplements] fluff," said geriatrician-internist Mary O'Brien, MD, associate professor of medicine at University of North Carolina at Chapel Hill. "But I think more and more physicians are realizing that we need to take a more proactive approach in taking care of the elderly and preventing problems. For the most part these are simple, safe things, if taken as directed." More than one a day A 1994 federal government health survey, the most recent available, found that a third of those interviewed had taken at least one vitamin or mineral supplement during the previous year. The numbers were even higher among older people, and experts believe use is continuing to climb. Some 42% of men between age 50 and 80, and 53% of women in that age group, had taken at least one supplement. Adult non-Hispanic white females were the most likely users. People with higher incomes tended to be major consumers. "As a physician I have learned how to guide patients through this process and not to encourage or discourage their use," said Bernd Wollschlaeger, MD, clinical associate professor of medicine and family practice at University of Miami (Fla.) School of Medicine. "After all, they will use them whether I want them to or not." Ginkgo biloba -- believed to be an aid in maintaining and improving memory and cognitive function, and possibly in preventing Alzheimer's disease -- is the No. 1 herbal remedy used by older people. St. John's wort is a popular treatment used by elderly women for mood disorders, including minor depression. Glucosamine and chondroitin sulfate are popular treatments for arthritis. "Vitamin supplementation is very popular because of the notion that they maintain quality of life and healthy living," Dr. Wollschlaeger said. Herbal supplements come in every imaginable form: teas, powders, tablets and capsules. Some 24,000 to 30,000 products are currently on the market, according to the National Institutes of Health. They are sold in pharmacies, health food stores and grocery stores; over the Internet; and in physicians' offices. "We can embrace some dietary and nutritional supplements," said Rebecca Costello, PhD, deputy director of the NIH Office of Dietary Supplements, which was established by Congress to foster supplement research. "But the herbals are very questionable, and the science base on many of them is scant." When a patient asks for advice, "the average physician just shrugs his shoulders," said George Lustig, MD, who chairs the Broward County (Fla.) Medical Society's complementary and alternative medicine committee. "They don't know enough to tell their patients, and until that paradigm is changed, the patient will be shortchanged," he said. A major concern is product purity. "All of these people are coming in with herbs and dietary supplements," said Texas family physician Robert P. Carroll Jr., MD, who last year called on the AMA to seek tighter regulation. "You don't know what crap you're getting with these things." Under the 1994 Dietary and Nutritional Supplement Health and Education Act, supplements are considered food, not drugs, and are not regulated by the Food and Drug Administration. Manufacturers are restricted from marketing them as remedies to treat, prevent or cure disease. But many skirt that rule by promoting them as aids to "improve joints" and "restore well-being," rather than saying they treat arthritis or depression. There are no standards governing concentrations of key ingredients, which can vary widely, "which doesn't allow the physician to prescribe the product in an analytical fashion," said Dr. Wollschlaeger, who trained in Germany, where the government requires standardization of ingredients. "Physicians are caught in between," he said. "They hear about all these studies -- often contradictory -- on various products, that say there's a place to utilize, for example, St. John's wort in the treatment of minor depression or ginkgo biloba in the treatment of early dementia. Then physicians have to determine which product is safe and efficacious for their patients. "A ginkgo biloba product on a store shelf is not necessarily the same ginkgo biloba used in the study. Physicians, actually, are lost. Good guidelines do not exist." There are other concerns about side effects and possible drug interactions between supplements and prescription medications, especially in elderly patients, a group taking larger quantities of medicines. "It's a potentially devastating problem," Dr. O'Brien said. "Physicians are very good at asking patients about the prescription medications they take, but we need to do a better job asking specifically about over-the-counter preparations -- and, even more specifically, about the vitamins, minerals and herbs they're taking -- and document that in the medical record." A common problem involves patients facing surgery who use ginkgo biloba, which can cause excessive bleeding during surgical procedures. Vitamin E also can cause bleeding in high doses. "The physician may have told the patient to stop taking aspirin, but nobody has told the patient to stop taking ginkgo biloba," Dr. Wollschlaeger said. "If the patient is on antidepressant medication and takes St. John's wort, it can intensify the effects of the antidepressant and cause severe side effects. It's crucial that we educate and develop guidelines for the health care professional. And we have to proactively educate patients to avoid potential side effects, because herbs and vitamins are pharmacologically active substances." Other dangerous combinations include St. John's wort and Zoloft or Prozac -- and even St. John's wort and cough syrup. An ingredient in cough syrup, dextromethorphan, combined with St. John's wort can cause serotonin syndrome, a condition of high fever, confusion, muscle rigidity, profuse swelling and diarrhea. St. John's wort also has been found to decrease the effectiveness of oral contraceptives, a protease inhibitor used to treat HIV/AIDS and the heart medication digoxin. Some supplements, including chaparral, thought to prevent cancer, have been linked to liver damage. Some studies suggest St. John's wort, valerian root and kava-kava may prolong the effects of certain anesthetics and impair awakening from anesthesia. "A lot of physicians don't think supplements are effective so they don't worry about it," said Lisa Colodny, PharmD, clinical coordinator of pharmacy services at Broward General Medical Center in Fort Lauderdale, Fla. But some of them, including St. John's wort and valerian root, have to be tapered off slowly before they're stopped. The hospital recently documented two cases within two days involving adverse medication reactions, she said. One involved ginkgo biloba and Coumadin. "A potentially dangerous assumption is that supplements 'may not help me but they won't hurt me,' " she added. "The problem is that we don't have a lot of information that's science-based that says that they're helpful or harmful." Doctors can't always persuade their patients to discontinue them, either. "You may not convince that little old lady to stop taking that ginkgo with her Coumadin," said Dr. Colodny. "Instead, ask her to have her blood tested more frequently. Educate patients about what could happen so you're proactive about preventing the adverse effects." Diet vs. supplements Isn't maintaining a healthy, balanced diet enough? Ideally, yes, Dr. O'Brien said. "But the truth is, most people don't," she said. "A shocking percentage of older people have nutritional deficiencies. By taking a multivitamin-multimineral supplement, they're just covering all the nutritional bases." Scurvy, a vitamin C deficiency once identified with sailors hundreds of years ago, is now being seen among several population groups, including the homeless and elderly men living alone. For that reason, Dr. O'Brien recommends older people consume children's chewable supplements twice a day with meals. Dr. Herbert, on the other hand, argues that only a few supplements are generally desirable, including the following:
People with serious medical conditions, including cancer, diabetes, hypertension, thyroid disorders and heart disease should avoid taking supplements without physician supervision, Dr. O'Brien said. "For others, the best approach is for doctors to be open-minded and approachable," she said. "Folks don't want to tell you about the Benadryl they're taking over the counter, much less the echinacea. In most cases, they don't want to confide because they're afraid of reproach, criticism and feeling foolish. Unless our patients trust us, we're going to be operating without complete information." When Dr. Carroll senses that a patient is using supplements, he tells them to bring them in. "If I get a bag filled with herbal medicine, four or five laxatives, two or three dietary supplements and a whole lot of stuff that's not given by a doctor, it's time for a lecture." But Dr. Costello said doctors also should ask themselves if the treatments they're prescribing are themselves causing problems that could lead patients to seek relief elsewhere. And despite the concerns, doctors shouldn't reject supplements out-of-hand, Dr. O'Brien said. "What a smart physician does is be open-minded and take the best of both worlds and combine that in a manner that fits the needs of the individual patient." Supplemental advice What should doctors tell their patients about dietary and nutritional supplements?
Weblink American Herbal Products Assn. (http://www.ahpa.org/) A member organization of manufacturers of herbal products that are promoted as remedies to enhance health and quality of life American Nutraceutical Assn. (http://www.americanutra.com/) A group that provides educational materials, continuing education programs for health professionals and a comprehensive online database on supplements ConsumerLab (http://www.consumerlab.com/) A nonprofit organization that provides independent test results and information to help consumers and health care professionals evaluate health, wellness and nutrition products Food and Drug Administration (http://www.cfsan.fda.gov/) Information about supplements from the FDA Center for Food Safety and Applied Nutrition National Institutes of Health International Bibliographic Information on Dietary Supplements (http://odp.od.nih.gov/ods/databases/ibids.html) A database of published, international, scientific literature on dietary supplements Richard T Herrick,MD herrickclinic@mindspring.com www.herrickclinic.com
|
