Why dark chocolate makes people feel calm

Research from Swinburne University of Technology has found that the polyphenols in dark chocolate increase calmness and contentedness.

Polyphenols are found naturally in plants and are a basic component of the human diet. These compounds have been shown to reduce oxidative stress, which is associated with many diseases. They may also have beneficial psychological effects.

“Anecdotally, chocolate is often linked to mood enhancement,” Swinburne PhD candidate and lead author of the study Matthew Pase said.

“This clinical trial is perhaps the first to scientifically demonstrate the positive effects of cocoa polyphenols on mood.”

Seventy-two healthy men and women aged 40–65 years took part in the randomised study to receive a dark chocolate drink mix standardised to contain either 500mg of cocoa polyphenols, 250mg of cocoa polyphenols or no cocoa polyphenols. The drink mixes were given to participants in identical packaging so that both the investigators and participants were unaware of which treatment they were receiving. Participants drank their assigned drink once a day for 30 days.

After 30 days, those who drank the high dose concentration of cocoa polyphenols reported greater calmness and contentedness than those who drank either of the other drink mixes.

The researchers failed to find any evidence that cocoa polyphenols significantly improved cognitive performance. Additionally, only those who consumed the highest amount of polyphenols (500mg per day) reported any significant positive effects. Participants who consumed a moderate amount (250mg per day) reported no significant effects. The research is published in the May issue of the Journal of Psychopharmacology.