Beneficial effects of dark chocolate consumption (in moderation, of course) on cardiovascular health have been reported in several studies, with this effect linked to the high levels of polyphenolic flavonoids found in dark chocolate or cocoa. But how, exactly, does flavonoid-rich dark chocolate take a bite out of cardiovascular mortality?

In research reported by Wirtz et al., the authors questioned whether this protective effect was exerted through a reduction in stress reactivity – and whether this stress-busting effect occurs in the periphery or more centrally. Psychosocial stress, the investigators noted, has been implicated as a cardiovascular disease risk factor, presumably by inducing physiological stress responses and hyperactivation of the hypothalamus-pituitary-adrenal axis and the sympathetic nervous system.