STEVE INSKEEP, host:
Sales of red wine supplements have grown by more than 300 percent over the past year. Their popularity of red wine supplements since stems from a couple of research studies published last year, which found that mice who were fed a component of wine called resveratrol live longer.
Here is NPR's Allison Aubrey.
ALLISON AUBREY: The allure of a magic elixir can tempt even the savviest consumer. Writer and filmmaker Daedalus Howell was so intrigued by resveratrol when he first heard about it, he offered to be a human test subject in a study to see if the longevity effect found in mice holds up in people too. We caught up with him on his cell phone in California as he shopped at a busy Sonoma Valley market that sells supplements and wine.
Mr. DAEDALUS HOWELL (Writer, Filmmaker): There are certainly people who are buying wine. I'm going to open a wine in a few minutes, but only just to let it, you know, get some air.
AUBREY: Howell says so far researchers have not taken him up on his offer to be a test subject. And it turns out there's very little known about how the red wine compound acts in the human body.
This hasn't stopped people from buying supplements. A new analysis from ConsumerLab.com tested 13 products. It found that compared to the amount given to mice, the supplements contained relatively little resveratrol.
One product tested called Revatrol contained, according to its label, 400 milligrams of a whole red-wine-grape complex, with an unspecified amount of resveratrol.
Mr. TOD COOPERMAN (President, ConsumerLab.com): Clearly, a consumer can be misled.
AUBREY: Tod Cooperman is president of ConsumerLab.com.
Mr. COOPERMAN: This happens often with supplements, where a consumer goes out to buy a certain ingredient. They see a product that sounds like it has that ingredient. In this case, they're looking for resveratrol. This product is called the Revatrol. And they really have no idea that the amount of active ingredient can be just a miniscule amount of the total.
AUBREY: In this case, the lab test found just two milligrams of resveratrol per caplet, less than one percent of the total blend. Now, since the quantity of resveratrol was not listed, it is an accurate label.
But company's James DiGeorgia says just after ConsumerLab.com purchased their caplets last January for testing, he released a new version of Revatrol.
Mr. JAMES DiGEORGIA (Revatrol): We changed the formula and improved the formula and specifically put exactly what's in the formula. So there's nothing misleading about our label or our advertising.
AUBREY: Two products tested by ConsumerLab.com did contain much less resveratrol than what's stated on the label. One distributor, Life Extension, based out of Fort Lauderdale, says it's looking into the results.
And since there's no official recommended dose for resveratrol and no government regulation of the supplement, distributors are free to sell and say almost anything about their products. The FDA doesn't step in unless there are reports of harm.
Physician William Gruss, a paid spokesman for Revatrol, says he thinks the red wine capsules are safe, and since he's been taking them, he says he's noticed benefits.
Dr. WILLIAM GRUSS (Revatrol): I felt suddenly more energy. I felt more endurance. Actually, I've even lost weight.
AUBREY: These kinds of personal testimonies worry the Mayo Clinic's Brent Bauer, a physician who specializes in alternative medicine. He says consumers really need to be more discriminating. Bauer says there are intriguing findings in the animal studies of resveratrol, showing the compound has anti-oxidant and anti-inflammatory properties.
Dr. BRENT BAUER (Alternative and Complementary Specialist, Mayo Clinic): The challenge, of course, is that we don't what have any good clinical trials, in other words human trials.
AUBREY: And the toxicity review underway by the National Institutes of Health won't be finished for a few years. With all the unknowns, writer and wine lover Daedalus Howell says he'll stick with the time-tested way of the imbibing grape extract.
Mr. HOWELL: Wine drinking, of course, goes back eons, and it's certainly a romantic endeavor. And I don't think there's anything terribly romantic about taking a supplement. You ever show up at somebody's house with a supplement and flowers? What kind of date is that?
AUBREY: For those who are interested in supplements, the distributors of Revatrol say they will do follow-up testing to confirm that their new formulation contains exactly what the label states.
Allison Aubrey, NPR News.
INSKEEP: And that's Your Health on NPR News.
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