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.

Why does anyone believe this works? The dangers of cupping.

Cupping therapy. If this looks painful and possibly damaging

to the skin, that's because it is.

People are easily fooled. Even smart people.

I'm not talking about voters in the U.S. and the UK, although both groups have recently demonstrated how easily they can be conned into voting against their own interests. You can read plenty of articles about that elsewhere.

No, I'm talking about the wide variety of health treatments that call themselves alternative medicine, integrative medicine, traditional Chinese medicine, energy medicine, and other names. These are all just marketing terms, but many people, including some physicians and scientists, seem captivated by them.

This week I'm going to look at "cupping," a rather bizarre treatment that, for reasons that escape me, seems to be growing in popularity.

I just returned from a scientific conference, where I happened to speak with an editor for a major scientific journal who also follows this blog. She remarked that she liked some of my articles, but she disagreed with me about cupping, which I wrote about during the 2016 Olympics, where swimmer Michael Phelps was observed to have the circular welts that are after-effects of cupping. This editor's argument boiled down to "it works for me," which left me somewhat flabbergasted.

And just two weeks ago, when I was at my physical therapist's office getting treatment for a shoulder injury, I heard her discussing cupping with another therapist. I then noticed a large box containing cupping equipment on one of the counters. Thankfully, my therapist didn't suggest cupping for me; I'm not sure how I would have replied.

What is cupping? It's a technique where you take glass cups, heat the air inside them, and then place them on the skin. Because hot air is less dense, it creates suction as it cools, which sucks your skin up into the glass. (Some cupping sets use pumps rather than heat to create this effect.) Imagine someone giving you a massive hickey, and then doing another dozen or so all over your back, or legs, or wherever the cupping therapist thinks you need it. If that sounds kind of gross, it is.

Quacktitioners Practitioners of cupping think that it somehow corrects your "qi," a mysterious life force that simply doesn't exist. When pressed, they often remark that it "improves blood flow," a catch-all explanation that has no scientific basis and that is more or less meaningless. What really happens, as the physician and blogger Orac noted, is this:

"The suction from cupping breaks capillaries, which is why not infrequently there are bruises left in the shape of the cups afterward.... If you repeatedly injure the same area of skin over time ... by placing the cups in exactly the same place over and over again, the skin there can actually die."

So maybe cupping isn't so good for you.

Cupping is ridiculous. There's no scientific or medical evidence that it provides any benefit, and it clearly carries some risk of harm. A recent review in a journal dedicated to alternative medicine–one of the friendliest possible venues for this kind of pseudoscience–concluded that

"No explicit recommendation for or against the use of cupping for athletes can be made. More studies are necessary."

Right. That's what proponents of pseudoscience always say when the evidence fails to support their bogus claims. Let us do more studies, they argue, and eventually we'll prove what we already believe. That's a recipe for bad science.

Even NCCIH, the arm of NIH dedicated to studying complementary and integrative nonsense medicine, can't bring itself to endorse cupping. Their summary states:

• There’s been some research on cupping, but most of it is of low quality.
• Cupping may help reduce pain, but the evidence for this isn’t very strong.
• There’s not enough high-quality research to allow conclusions to be reached about whether cupping is helpful for other conditions.

In other words, some bad scientists have conducted a few studies but haven't proven anything. But wait, it gets worse. NCCIH goes on to warn that:

• Cupping can cause side effects such as persistent skin discoloration, scars, burns, and infections, and may worsen eczema or psoriasis. 
• Rare cases of severe side effects have been reported, such as bleeding inside the skull (after cupping on the scalp) and anemia from blood loss (after repeated wet cupping). 

And still, otherwise intelligent people say "it works for me." I'm left speechless.

The bottom line: save your money and your skin. Don't let anyone suck it into those cups.