On Nutrition

Whether you want to stay sharp with age or boost your workday productivity, cognitive health supplements may sound appealing. These supplements form a booming segment of the overall dietary supplement industry. But are they effective? Are they safe? Let’s put it this way: In early 2019, the Food and Drug Administration (FDA) warned that many supplements promoted to prevent, treat or cure Alzheimer’s disease and dementia use unproven claims in their marketing. The agency issued warning letters, but that hasn’t prevented sales of these products.

Some supplements promoted for memory or cognitive clarity contain drugs that have not been approved by the FDA and are not allowed to be sold as dietary supplements, yet they are easily purchased online. For example, vinpocetine — a synthetically produced compound sometimes referred to on product labels as Vinca minor or periwinkle extract — is found in many supplements marketed for enhanced memory, focus or mental acuity. In June 2019, the FDA issued a consumer warning that vinpocetine can cause miscarriage or harm fetal development if used during pregnancy.

Another ingredient openly available for sale despite not being approved for use by the FDA is piracetam, which lacks sufficient evidence to support use for dementia or other cognitive problems. More alarmingly, a 2020 analysis in JAMA Internal Medicine of dietary supplements containing piracetam found that the amount contained in the manufacturer-recommended daily dosages ranged from 831 milligrams to the potentially dangerous 11,283 milligrams. Another 2020 study that examined 10 supplements listing piracetam as an ingredient detected three additional unapproved drugs in their samples. This is concerning because in most cases the drugs weren’t listed on the product label — and because one of the drugs can be addictive and has led to dozens of hospitalizations.

Some popular supplements advertised on TV claim to be “clinically” proven, but in fact are not. Notably, the maker of Prevagen is embroiled in an ongoing legal battle with the Federal Trade Commission and the attorney general of New York state. The charges are that Prevagen claims of improving memory and supporting healthy brain function, including a “sharper mind” and “clearer thinking,” are false and unsubstantiated. Prevagen’s main ingredient, apoaequorin, a protein isolated from the Aequorea victoria jellyfish, has no known role in memory or cognitive function. A 2016 independent review by the Alzheimer’s Drug Discovery Foundation said it was unlikely to have any benefits for brain health, noting that the one company-sponsored randomized controlled trial did not show that apoaequorin worked better than a placebo.

In 2012, the FDA sent Prevagen’s manufacturer a letter warning that the company was violating federal law, alleging that the active ingredient was a synthetic copy of apoaequorin that had never been part of the human diet or sold in supplements. The agency also documented 1,000 “adverse events” between 2008 and 2011, including chest pain, vertigo and seizures.

Other supplements have only a few small studies to back them up. The popular supplement Neuriva claims to increase focus, accuracy, memory, learning and concentration. Neuriva contains an extract of coffee cherry — coffee beans are the seeds of the coffee cherry. The claims about coffee cherry extract are not in line with basic human biology, and the only research showing any benefits was funded and conducted by coffee fruit extract manufacturers.

The bottom line is that the FDA is not authorized to review supplements for safety or effectiveness before they are sold to consumers, so buyer beware. Overall, there’s no evidence that supplements have major benefits beyond diet and lifestyle.