. . . Well, it can be good for you:
A new Australian study has found dark chocolate may increase calmness and contentedness through the polyphenols found in cocoa.
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, and may also have beneficial psychological effects.
Anecdotally, chocolate is often linked to mood enhancement,” Matthew Pase, a PhD candidate at the University of Swineburne in Melbourne and lead author of the study, says. . .
“This clinical trial is perhaps the first to scientifically demonstrate the positive effects of cocoa polyphenols on mood.” . . .
Sadly I don’t think this is the sort of medicine to which you can apply the rule that if some is good, more is better.