Few things are more unnerving than the memory lapses most of us experience as we grow older. Younger people forget things all the time, of course, but for their elders these lapses (the mislaid word, name, key or to-do list) call up the threat of permanent memory loss, as in Alzheimer’s disease, possibly the most feared of all disorders. Naturally, we yearn for a pill to prevent mental decline.
There are numerous dietary supplements marketed to improve memory. All sorts of herbs (notably ginkgo), vitamins and fish oil, as well as countless cocktails of herbs and other ingredients (such as Focus Factor, BrainReload, and Brain Alert), come with more or less blatant claims that they aid memory and mental ability.
But all of them, with the possible exception of fish oil supplements, have little or no basis for such claims. If a supplement ever turns out to boost memory or help prevent dementia, we hope to be the first to tell you. Meanwhile, here’s a rundown of the latest scientific evidence about some of the most widely promoted ingredients.
One of the best-selling products in the U.S. for memory loss, ginkgo is an ingredient in many so-called brain boosters. It comes from the maidenhair tree (Ginkgo biloba) and is widely prescribed in Europe for “cerebral insufficiency,” which can mean anything from confusion to depression and anxiety.
A dozen years ago, a study found that ginkgo improved mental functioning in people with Alzheimer’s, but despite a flood of studies since then, the evidence remains inconsistent. In one of the few studies to compare ginkgo with a standard drug approved for use in treating Alzheimer’s disease, a small Italian study in 2006 found ginkgo as effective as donepezil (Aricept) in improving memory and attention in people with mild to moderate Alzheimer’s. However, a review of 35 studies by the Cochrane Collaboration in 2007 concluded that the overall evidence for ginkgo as a treatment for dementia or cognitive impairment is “inconsistent and unconvincing.”
As for prevention trials, a large, well-designed study of healthy people 75 and older in 2008 found no evidence that ginkgo helps prevent dementia, including Alzheimer’s. In 2009, a follow-up study published in the Journal of the American Medical Association found that the supplement did not slow cognitive decline or memory loss in any way.
Finally, in late 2012, a well-designed French study published in Lancet Neurology looked at 2,820 people aged 70 and older with self-reported memory complaints, half of whom took EGb761 (a standardized gingko extract used in many clinical trials and often prescribed in Germany and France) twice daily, half a placebo. After five years, ginkgo did not slow the rate of progression to Alzheimer’s.
Phosphatidylserine (PS) is a type of fat found in brain cells, as well as other cells in plants and animals. The Memory Cure, a perennial bestseller, touts PS supplements as a way to prevent Alzheimer’s. Derived from cow brain until the advent of mad cow disease, PS is now extracted from soy. A few preliminary studies suggested that PS might help elderly people with dementia. Though it has been much studied since, however, there’s no convincing evidence it’s useful for treating dementia or for preventing it in healthy people.