Researchers invited 30 healthy, college students to participate in a study to examine the effects of chocolate on vision and thinking (cognitive) abilities. For the first portion of the study, half of the participants ate a single serving of dark chocolate, while the other half ate white chocolate. For the second portion of the study, the groups switched to the other type of chocolate, and for one week in between, participants ate no chocolate at all.
Everyone in the study completed tests of visual function and thinking ability approximately two hours after eating 35 grams (1.25 ounces) of dark or white chocolate. The researchers found that those eating dark chocolate performed significantly better on these tests than those eating white chocolate:
Dark chocolate contains dozens of nutrients called flavonols and health experts theorize that dark chocolate improves brain function because flavonols improve blood flow to the brain. This study supports this hypothesis: that improvements in visual and thinking ability after eating dark chocolate indicate this food may improve brain function. White chocolate does not contain these healthful nutrients.
These tips for enjoying dark chocolate just may give your brain that extra edge to power through the toughest mental tasks, without expanding your waistline.
(Physiol Behav 2011; 103:255–60)
Suzanne Dixon, MPH, MS, RD, an author, speaker, and internationally recognized expert in chronic disease prevention, epidemiology, and nutrition, has taught medical, nursing, public health, and alternative medicine coursework. She has delivered over 150 invited lectures to health professionals and consumers and is the creator of a nutrition website acclaimed by the New York Times and Time magazine. Suzanne received her training in epidemiology and nutrition at the University of Michigan, School of Public Health at Ann Arbor.