The researchers examined the data of 968 participants of the Maine-Syracuse Longitudinal Study (MSLS), which looks at cardiovascular risk factors and cognitive functioning in adults. The participants ranged in age from 23 to 98.
A Nutrition and Health questionnaire was used to measure the participants’ demographics and lifestyle characteristics, as well as their dietary intake. They self-reported how frequently they consumed a list of foods, including meat, fish, eggs, breads, vegetables, nuts, and chocolate. Their cognitive function was assessed using the MSLS neuropsychological test battery.
The researchers found that cognitive performance, across a range of cognitive domains, was significantly higher in those who consumed chocolate at least once per week than in those who never or rarely consumed chocolate. These domains include the Global Composite Score, Visual-Spatial Memory and Organization, Working Memory, Scanning and Tracking, Abstract Reasoning, and the Mini-Mental State Examination.
“The findings suggest that it’s not just a global ability that’s affected by eating chocolate, but also specific abilities are being affected,” said Merrill Elias, one of the study’s authors. “It’s not too surprising to me, because generally when we have these kinds of variables that effect things either negatively or positively, they effect multiple abilities.”
In a secondary analysis of 333 participants, the researchers considered whether it was cognitive performance that determined chocolate consumption, rather than the other way around. However, there were no significant predictions of chocolate consumption based on cognition. The authors are also planning to conduct a follow-up study that would differentiate between various types of chocolate (dark, milk, white, etc).
Previous studies have linked chocolate consumption to cardiovascular health benefits and reduced levels of stress, but little has been known about its effects on human cognitive performance—until now. But just how much chocolate should we eat to reap the benefits?
“We don’t want people to start eating six candy bars a night,” Elias said. “People think, if a little bit is good for me, then a lot is better, but it generally doesn’t work out that way. We’re not looking at people eating chocolate for breakfast, lunch, and supper. We’re saying that if you’re consuming chocolate and you’re doing it sensibly, that may not be bad. It actually may be good for you.”