Does ginkgo biloba enhance memory? I forgot.

I recently saw an ad that claimed ginkgo biloba can treat the signs of dementia. A quick search on Amazon.com yielded hundreds of products, many claiming that gingko is a "brain sharpener" or that it "supports focus, memory, brain function and mental performance," or other similar claims.

Ginkgo biloba is a supplement made from the leaves of the gingko biloba tree, which is native to China. The supplements industry claims that gingko has been used for thousands of years to improve memory and stave off dementia. While that may be true (though I doubt it), the argument that a medical treatment was used by pre-scientific cultures is not exactly compelling. After all, people died very young in ancient times, and medical knowledge was little more than superstition, for the most part. I don't know about you, but when I'm looking for medicine, I want the latest stuff.

"But wait!" say ginkgo biloba's advocates: maybe those ancient folk doctors were onto something. Maybe so–and it didn't take me long to find multiple studies testing what those ancients supposedly believed about gingko biloba:

1. Here's a review from 2009 that looked at gingko biloba for dementia and milder cognitive impairment. It reported that "the evidence that Ginkgo biloba has clinically significant benefit for people with dementia or cognitive impairment is inconsistent and unreliable." Not exactly a ringing endorsement.
2. Here's another study, from 2012, looking at the effect of gingko biloba on memory in healthy individuals. Is it a "brain sharpener"? Well, no. This study found that gingko "had no ascertainable positive effects on a range of targeted cognitive functions in healthy individuals." In other words, a total dud.
3. And here's an even more recent study, from 2015. The result: "no convincing evidence ... that demonstrated Ginkgo biloba in late-life can prevent the development of dementia. Using it for this indication is not suggested."

Given that the science says this doesn't work, you might wonder how it is that hundreds of gingko biloba products are still on the market, all of them with claims about memory. Simple: it's a dietary supplement, not a drug, which means that it is essentially unregulated (in the U.S.). The FDA won't step in unless the marketing claims get so outrageous that they cross the line into medicine–and even then, the FDA rarely does more than send a sternly worded letter.

As I've written before, supplement marketing is like the wild west. You generally can't trust anything you read from the manufacturers, except perhaps the ingredients list. And even the ingredients are sometimes inaccurate and contaminated.

(By the way, I find it especially amusing when a pill that has no effect is advertised as "double strength," as Walgreens does for one of their gingko products, here.)

So be skeptical about the marketing claims for gingko biloba. Even NCCIH, the NIH institute whose mission is to promote "alternative" medicine, is remarkably clear about this, stating that:

• "There’s no conclusive evidence that ginkgo is helpful for any health condition.
• Ginkgo doesn’t help prevent or slow dementia or cognitive decline.
• There’s no strong evidence that ginkgo helps with memory enhancement in healthy people, blood pressure, intermittent claudication, tinnitus, age-related macular degeneration, the risk of having a heart attack or stroke, or with other conditions."

I must say, I'm feeling a bit better about NCCIH these days. They got this one right. The bottom line: don't waste your money on gingko biloba.