Chocolate and mood

Individuals who screen positive for possible depression appear to consume more chocolate than those not screening positive for depression, according to a report in the 22 April issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

"A rich cultural tradition links chocolate consumption with putative mood benefits," the authors write as background information in the article. Several potential mechanisms for these benefits have been proposed, but little scientific research has examined the association between chocolate and mood in humans.

Natalie Rose, MD, of University of California, Davis, and University of California, San Diego, and colleagues examined the relationship between chocolate and mood among 931 women and men who were not using antidepressants. Participants reported how much chocolate they consumed and most also completed a food frequency questionnaire about their overall diet. Their moods were assessed using a previously validated depression scale.

Those who screened positive for possible depression consumed an average of 8.4 servings of chocolate per month, compared with 5.4 servings per month among those not screening positive. Those whose scores were even higher, reflecting probable major depression, consumed even more chocolate – 11.8 servings per month.

Findings were similar among women and men. "Several nutrient factors that could be theorised to drive the appearance of a putative chocolate-mood association, such as caffeine, fat, carbohydrate and energy intake, bore no significant correlation with mood symptoms, suggesting relative specificity of the finding," the authors write. There was also no difference in the consumption of other antioxidant-rich foods – including fish, coffee, caffeine and fruits and vegetables – between the two groups.

Several explanations for the findings are possible, the authors note. "First, depression could stimulate chocolate cravings as ‘self-treatment’ if chocolate confers mood benefits, as has been suggested in recent studies of rats. Second, depression may stimulate chocolate cravings for unrelated reasons, without a treatment benefit of chocolate (in our sample, if there is a ‘treatment benefit’, it did not suffice to overcome the depressed mood on average). Third, from cross-sectional data the possibility that chocolate could causally contribute to depressed mood, driving the association, cannot be excluded."

In addition, a physiological factor such as inflammation could drive both depression and chocolate cravings, or more complex relationships may exist. For instance, the mood-elevating, craving-triggering effects of chocolate may be counteracted by ingredients that often accompany chocolate products, including artificial trans fats that inhibit omega-3 fatty acid production. "Future studies are required to elucidate the foundation of the association and to determine whether chocolate has a role in depression, as cause or cure," the authors conclude.

(Source: JAMA/Archives: Archives of Internal Medicine: May 2010)