STEVE INSKEEP, host:
If you cannot resist chocolate, a new study offers a reason not to feel so guilty about eating small amounts, like, say, that bag of chocolate chip cookies that somebody brought into our studios this morning. Anyway, researchers have made a surprise finding. People who eat chocolaty foods may benefit from an aspirin-like effect.
NPR's Allison Aubrey reports.
ALLISON AUBREY: For people who are passionate about chocolate, the news is a boost. Take Cheri Davis Gardner(ph), who guiltlessly picks up a chocolate-covered macaroon at a Washington bakery.
Ms. CHERI DAVIS GARDNER (Chocolate Lover): It's the food of the gods, so it's wonderful. So I eat it and I like it.
AUBREY: Resisting chocolate is nearly impossible for some people, researchers at Johns Hopkins learned this last year after recruiting over 1,000 men and women to participate in a study. The goal was to figure out why some people benefit more from aspirin's blood-thinning effect. At the beginning of the study, the researchers instructed everyone to completely avoid chocolate, strawberries, grapes and teas, which are all thought, at high levels, to affect blood platelet activity.
But lead researcher Diane Becker says 140 people blew it and fessed up to eating chocolaty foods.
Dr. DIANE BECKER (Professor of Health Policy and Management, Johns Hopkins University): Chocolate chip cookies and cake and ice cream, and they consumed relatively small amounts because they knew they weren't supposed to be eating it.
AUBREY: These people could no longer be part of the aspirin study. Becker called them the chocolate offenders, but she decided to study their blood, too. In one test, she ran the offenders' blood through a mechanical blood vessel system, basically a hair-thin plastic tube which is designed to measure how long it takes the platelets to clump together or form a mini-blood clot.
Dr. BECKER: Then what normally happens is that there is a time that's known to be the normal amount of time that everybody would do. What happens with chocolate is it actually increases that amount of time.
AUBREY: Meaning it takes more time for the platelets to clump and close off the blood vessel tube. This is advantageous because blood clots can lead to heart attacks and strokes. Becker says prior laboratory stories have shown that mega-doses of dark cocoa do seem to have this anti-clumping effect, but she never guessed the effect would hold up in her offenders group.
Dr. BECKER: I was very surprised that that small amount of causual consumption of chocolate would have this big an effect.
AUBREY: The results are exciting for Becker, who carried out this study independently with no funding from the chocolate industry. But she says it's important to put the findings in perspective. Chocolate should never be mistaken as a medicine. Even if it can produce an anti-clumping effect similar to aspirin, chocolate is nowhere near as potent.
Dr. BECKER: With aspirin it's much more dramatic.
AUBREY: Becker presented her findings to the American Heart Association's annual meeting this week. They've yet to be published, but researcher Alice Lichtenstein of Tufts University says the study is intriguing. The assumption has been that it's only pure forms of dark chocolate, rich in chemicals called flavanols, that have any beneficial effect at all.
But Lichtenstein says since Becker's chocolate offenders weren't eating pure chocolate and may have been eating cookies and cakes with very low levels of flavanols, it raises all sorts of new questions.
Dr. ALICE LICHTENSTEIN (Director of Cardiovascular Nutrition Lab, Tufts University): So then we have to step back and say, well, is it chocolate, is it flavanols, is it something else associated with people eating chocolate?
AUBREY: So for now Lichtenstein's advice is to enjoy a little chocolate if you love it, but don't assume it's helping your heart. As for chocoholic Cheri Davis Gardner...
Ms. GARDNER: I never feel guilty about chocolate. It's the sugar that's bad.
AUBREY: And the calories from fat, too. But she says the food of the gods is still heavenly in moderation.
Allison Aubrey, NPR News, Washington. Transcript provided by NPR, Copyright NPR.