Remember though, it has to be 70% + dark chocolate, and made with proper cocoa butter NOT palm oil:
There is, however, other evidence that chocolate has health benefits. A review (admittedly not a systematic one, which would be more reliable, since it would tell you how the studies included in the review were chosen) of cocoa and cardiovascular health in the journal Circulation suggests that epicatechin, a specific flavanol, may have antioxidant and anti-inflammatory effects that protect the inner walls of blood vessels from atherosclerosis. So chocolate may be due some credit for widening blood vessels, keeping their lining smooth and increasing blood flow.
Chocolate has also been found, in some studies, to reduce blood pressure and the risk of stroke. Dark chocolate, with 70% cocoa solids, is the healthiest, since it has little sugar, its fat comes from cocoa butter and it contains iron and magnesium.