This file photo shows organic cocoa beans in storage at a factory in Ocumare de la Costa, Caracas, Venezuela. A large-scale study is being launched in 2014 to see if pills containing the nutrients in dark chocolate can help prevent heart attacks and strokes. It is sponsored by the National Heart, Lung and Blood Institute and Mars Inc., maker of M&M's and Snickers bars. The candy company has patented a way to extract flavanols from cocoa in high concentration and put them in capsules.