Dietary and Herbal Supplements and Alzheimer's: What Works?
Last updated: Oct 17, 2008
People often turn to vitamins and herbal medicines in the desperate search for something – anything – to stave off the symptoms of Alzheimer's disease once they begin. Unfortunately, the science to date mostly says "save your pennies."
This week marked another dead end: this time, of the once-promising idea that B vitamins can minimize brain deterioration. High-dose supplements of folate and vitamins B6 and B12 showed no effect on the symptoms of people with mild and moderate Alzheimer's in a clinical trial reported in the Journal of the American Medical Association. B vitamins reduce homocysteine, an amino acid that's found in higher amounts in people with Alzheimer's. In the trial, homocysteine levels did indeed drop in the subjects who took the supplements, but it didn't change their symptoms. It's unclear why.
Which begs the question, does any supplement work?
Vitamin supplements: Earlier this year, a study in the Journal of the American Geriatrics Society reported that using supplements of either vitamin C or vitamin E, or both of these antioxidants together, failed to slow the advance of Alzheimer's. This echoed previous studies. Vitamin E, still sometimes prescribed, has fallen out of favor since several major studies in 2005 discount its effectiveness. What's more, megadoses of vitamin E are linked to heart failure.
Herbal/alternative supplements: Not much better news here. No large, well-run clinical trials have definitively shown an herbal remedy to reverse or slow Alzheimer's symptoms. The trouble with herbals is that they're less well-studied than vitamins or drugs. So we have less data (and more wiggle room for false claims). Grape seed extract research earlier this year showed promise and is being tested further, for example. Coral calcium is an alternative that's been dismissed.
Worth remembering: "Natural" doesn't mean "always safe." Why not just try all the alternative possibilities anyway? Because we don't understand herbals' side effects or drug interactions any more than their benefits. For example, ginko balboa, a tree-leaf extract that may have modest positive effects on memory, can be dangerous for people on blood thinners. Chinese club moss, another popular supplement now in clinical trial, can't be taken with the dementia drugs Aricpet, Exelon, or Razadyne.
Bottom line: Supplements should be approached warily for someone with dementia -- and ideally under the advice and supervision of a physician.
Finally, if you're looking to avoid dementia: The substances I've described have been in the context of treating dementia. Alas, there's scant evidence they can prevent Alzheimer's, either. Omega three fatty acids are among the preventatives being looked into, but, again, it's inconclusive.
Caregivers' best bet: Maintain a normal weight, take a multivitamin to help get all the basic nutrients you need, don't smoke or drink to excess, and, above all, stay heart-healthy to avoid high blood pressure and diabetes. For now, that's still the best prevention advice around.