Researchers at Johns Hopkins University in Baltimore, MD tested the effect of dark chocolate on platelet activity, C-reactive protein and lipid profile in 28 healthy volunteers. For one week the volunteers ate dark chocolate (providing 700 mg of flavonoids per day). After seven days of regular dark chocolate ingestion, LDL cholesterol fell by 6% and HDL cholesterol rose by 9%. Dark chocolate reduced CRP levels. See http://www.raysahelian.com/cacao.html
My comments: It's okay to eat small amounts of dark chocolate, but larger portions can lead to weight gain and excessive exposure to sugars and fats. An alternative is taking a capsule of a cacao supplement in the morning with breakfast.