For the typical person, the difference between frequently eating or infrequently eating chocolate could account for a 5- to 7-pound difference, Golomb said.
The findings "certainly weren't explained by the chocolate eaters eating fewer calories. They ate more calories and didn't exercise any more," she said.
It's not clear, however, what kinds of chocolate the participants ate, although most would probably have interpreted the question as asking about candy, Golomb said. Milk chocolate is fattier than dark chocolate.
Golomb cautioned that the study does not say that chocolate consumption will help people lose weight.
"It is not a siren call to go out and eat 20 pounds of chocolate a day," she said.
However, the study suggests that diet composition may influence the body's metabolic processes, and therefore BMI, she said.
So why would chocolate fanciers be thinner than others? Dr. Daniela Jakubowicz, a professor at Tel Aviv University in Israel who has studied chocolate, said previous research has shown that diets that force people to avoid sweets actually make them more drawn to them. In her own research, she found that people were actually better able to tolerate a diet when they ate chocolate.
Golomb said that, ideally, future research will randomly assign some people to eat chocolate and others to avoid it. But that may be a challenge, especially if some participants refuse to go without it.
"We have a few pesky details to iron out," she said.
The study, funded by the U.S. National Institutes of Health, was published online March 26 in Archives of Internal Medicine.
For more about nutrition, visit the U.S. National Library of Medicine.
SOURCES: Beatrice A. Golomb, M.D., Ph.D., associate
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