Research to be published in the May issue of the Journal of Psychopharmacology has found cocoa polyphenols have a positive impact on mood in healthy individuals.
“To our knowledge, this is the first randomized, controlled trial to substantiate the effects of cocoa polyphenols on positive mood states in a non-clinical sample,” Matthew P. Pase of Swinburne University in Australia and his colleagues wrote in their study.
“Future research is needed to investigate whether cocoa polyphenols can ameliorate the symptoms associated with clinical anxiety or depression.”
The group of compounds are found naturally in the cocoa bean, the main constituent of dark chocolate. Many people believe consuming dark chocolate reduces anxiety and some research has even found that dark chocolate could improve mental functioning.
In the study of 72 healthy men and women aged 40–65 years, those who consumed a large amount of cocoa polyphenols in the form of a dark chocolate drink mix reported greater calmness and contentedness than those who consumed a chocolate drink mix that lacked polyphenols. The participants in the study maintained a relatively strict diet for 30 days to avoid consuming additional polyphenols.
The researchers failed to find any evidence that cocoa polyphenols significantly improved cognitive performance. Additionally, only those who consumed the highest amount of polyphenols (500 mg per day) reported any significant positive effects. Participants who consumed a moderate amount (250 mg per day) reported no significant effects.
Previous research suggests that cocoa polyphenols produce anti-anxiety effects by interacting with GABA receptors in the brain, Pase and his colleagues explained.
“Given the known actions of polyphenols on GABAa receptors, further human clinical trials are needed to substantiate the effects of cocoa polyphenols on anxiety and calmness.”