Supplements Won't Prevent Dementia

Donna Kaye Hill realized that her 80-year-old mother was faltering cognitively when her phone suddenly stopped working. When Ms. Hill called the phone company, “they told me she hadn’t paid her bill in three months.” Finding other alarming evidence of memory gaps, she took her mother, Katie, to a memory clinic. A geriatrician there diagnosed dementia and recommended two prescription drugs and a dietary supplement, a form of vitamin E. Katie Hill dutifully took vitamin E capsules, along with a host of other medications, until she died four years later. As she declined, her daughter didn’t think the vitamin, or the two prescription medications, was making much difference. “But if it doesn’t hurt, if there’s a chance it helps even a tiny bit, why not?” she reasoned. Ms. Hill, 62, a retired public employee in Danville, Va., takes fish oil capsules daily herself, hoping they’ll help ward off the disease that killed her mother. The elder Ms. Hill was unusual only in that a doctor had recommended the supplement; most older Americans are taking them without medical guidance. The Food and Drug Administration estimates that 80 percent of older adults rely on dietary supplements, many purporting to prevent or treat Alzheimer’s and other forms of dementia. Last month, the F.D.A. cracked down on this burgeoning market, sending warning letters or advisories to 17 companies selling about 60 supplements with names like Cogni-Flex and Mind Ignite. The warnings pointed out that the companies had touted these products as working like Alzheimer’s drugs, “but naturally and without side effects.” Or as “clinically shown to help diseases of the brain, such as Alzheimer’s.” The pills, oils and capsules were said to treat other diseases, too, from stroke to erectile dysfunction. Claiming that these products were intended for “the cure, mitigation, treatment or prevention of disease” meant that they were drugs, the agency’s letters said. And since they were drugs the F.D.A. had never reviewed or approved for safety and effectiveness, the companies now must submit applications for approval or stop making such claims. Over the past five years, the agency has taken action against 40 other products making Alzheimer’s claims. The supplements’ appeal is understandable. A growing older population with longer life spans means more people with dementia, though in population-based studies in this and other Western countries, its prevalence has fallen. More of us have seen the devastation up close and would do almost anything to evade it. But so far, the news about drugs and supplements has been discouraging. Although scientists have learned much more about dementia, the research literature and large pharmaceutical trials have mostly served to tell worried Americans about the many substances that don’t appear to prevent, treat or slow dementia. Vitamins, various antioxidants, ion Concocktderived from animals and plants — “we see plenty of ads on TV, but we have no evidence that any of these things are preventive,” said Dr. Steven DeKosky, a neurologist and deputy director of the McKnight Brain Institute at the University of Florida. Dr. DeKosky led a federally supported study of Ginkgo biloba extract, for instance, following more than 3,000 people for seven years to see if it reduced dementia. It didn’t. “No effects at all,” he said. “But look on the shelves. Many companies still sell ginkgo — if there’s really any in there, because supplements don’t always have the contents they say they have.” Moreover, “some of these supplements are biologically active and can cause toxicity when you take other drugs,” said Dr. DeKosky. Supplements can be costly, too. But there are other ways people can reduce their risk of dementia. Two prestigious panels, reviewing many prevention studies, recently came up with several recommendations.