Nutritionist Grishina named dark chocolate a source of iron, magnesium, copper and manganese 
bitter chocolate. According to her, a dark delicacy is considered to be one in which at least 55 percent of natural cocoa, while in milk only 25-35 percent, RIA Novosti reports.
“Dark chocolate is an excellent source of iron, magnesium , copper, manganese and other minerals, besides, it raises your spirits, “Grishina emphasized.