Good news for those who love chocolate. According to Japanese researchers, your ability to concentrate gets a boost if you eat a piece of black chocolate every day.

Chocolate has captured the imagination for centuries. There are indeed many stories on its potential health benefits. For example, chocolate would not only be good for your blood vessels, but it would also have a positive impact on brain function. In a new intervention study, Japanese researchers have examined whether this is indeed the case.

A total of 18 healthy adults between the age of 20 and 31 participated in the study, funded by the Japanese Association for Science Promotion. The scientists divided them into two groups. One group ate 24 grams of dark chocolate (70% cocoa) every day for 30 days. The second group received 24 grams of white chocolate daily.

Before, during and three weeks after the intervention period, the researchers subjected the participants to all kinds of tests. In particular, they measured the brain’s ability to concentrate and processing speed. They also measured the brain blood flow and the levels of certain substances that affect the brain cells. One of the substances that is important in learning processes is BDNF. They also determined the content of theobromine, an active substance in dark chocolate.

As expected, the levels of theobromine in the blood of the participants increased spectacularly after eating black chocolate. The black chocolate was also found to have a positive effect on their ability to concentrate. This effect was also still noticeable three weeks after the study. The brain blood flow and the level of BDNF did not increase. White chocolate had no positive effect.

This small, well-designed study shows that participants score better on concentration tests after eating black chocolate. A recent review of intervention studies also shows that cocoa has a small positive effect on the brain function. 

It is not clear how this happened. However, the researchers have included several hypotheses in their research. For example, better brain blood flow could be an explanation. But the research shows that this is not the case. Another hypothesis, namely that the positive effect of black chocolate would be due to an increase in BDNF, has not been demonstrated. The possible mechanism of action is therefore anyone’s guess.

More research is needed to figure this out. Once the mechanism of action has been clarified, we will have to see if the effect really makes a difference in everyday life. And whether the positive effect on brain function outweighs the negative effects of higher fat and sugar intake from eating chocolate. Chocolate, also black, remains an energy bomb.

Elena Mars

Born in London, England and raised in Orlando, FL, Elena graduated from the University of Central Florida with a bachelors' degree in Health Sciences. She later received her masters' in Creative Writing  from Drexel University. She writes part-time for the Scientific Origin and focuses mostly on health related issues.