The magical thing eating chocolate does to your brain

COURTESY THE INDEPENDENT

In the mid 1970s, psychologist Merrill Elias began tracking the cognitive abilities of more than a thousand people in the state of New York. The goal was fairly specific: to observe the relationship between people’s blood pressure and brain performance. And for decades he did just that, eventually expanding the Maine-Syracuse Longitudinal Study (MSLS) to observe other cardiovascular risk factors, including diabetes, obesity, and smoking. There was never an inkling that his research would lead to any sort of discovery about chocolate.

The chocolate effect

In the first of two analyses, Crichton, along with Elias and Ala’a Alkerwi, an epidemiologist at the Luxembourg Institute of Health, compared the mean scores on various cognitive tests of participants who reported eating chocolate less than once a week and those who reported eating it at least once a week. They found “significant positive associations” between chocolate intake and cognitive performance, associations which held even after adjusting for various variables that might have skewed the results, including age, education, cardiovascular risk factors, and dietary habits.

In scientific terms, eating chocolate was significantly associated with superior “visual-spatial memory and [organisation], working memory, scanning and tracking, abstract reasoning, and the mini-mental state examination.”

But as Crichton explained, these functions translate to everyday tasks, “such as remembering a phone number, or your shopping list, or being able to do two things at once, like talking and driving at the same time.”

In the second analysis, the researchers tested whether chocolate consumption predicted cognitive ability, or if it was actually the other way around–that people with better performing brains tended to gravitate toward chocolate. In order to do this, they zeroed in on a group of more than 300 participants who had taken part in the first four waves of the MSLS as well as the sixth, which included the dietary questionnaire. If better cognitive ability predicted chocolate consumption, there should have been an association between the people’s cognitive performance prior to answering the questionnaire and their reported chocolate intake. But there wasn’t.

“It’s not possible to talk about causality because that’s nearly impossible to prove with our design,” said Elias. “But we can talk about direction. Our study definitely indicates that the direction is not that cognitive ability affects chocolate consumption, but that chocolate consumption affects cognitive ability.”

What’s going on?

Why exactly eating chocolate is associated with improved brain function Crichton can’t say with absolute certainty. Nor can Elias, who admits that he expected to observe the opposite effect–that chocolate, given its sugar content, would be correlated with stunted rather than enhanced cognitive abilities. But they have a few ideas.

They know, for instance, that nutrients called cocoa flavanols, which are found naturally in cocoa, and thus chocolate, seem to have a positive effect on people’s brains. In 2014, one concludes that eating the nutrient can “reduce some measures of age-related cognitive dysfunction.” A 2011 study, meanwhile found that cocoa flavanols “positively influence psychological processes.” The suspicion is that eating the nutrient increases blood flow to the brain, which in turn improves a number of its functions.

Chocolate, like both coffee and tea, also has methylxanthines, the plant produced compounds that enhance various bodily functions. Among them: concentration levels. A number of studies have shown this, including one in 2004, and another in 2005.

Experts have known about the wonders of eating chocolate for some time. A lot of previous research has shown that there are, or at least could be, immediate cognitive benefits from eating chocolate. But rarely, if ever, have researchers been able to observe the impact of habitual chocolate eating on the brain.

The takeaway isn’t that everyone should rush to stuff their faces with the magical sweet. “I think what we can say for now is that you can eat small amounts of chocolate without guilt if you don’t substitute chocolate for a normal balanced healthy diet,” Elias said.