According to WebMD, dark chocolate is healthier than other forms of chocolate because it lowers high blood pressure, decreases the risk of heart attacks, enhances neurotransmitters that regulate sleep and is a source of antioxidants. However, studies report that these health benefits are negated if too much is consumed at once or the chocolate is eaten with milk.
WebMD cautions that dark chocolate is not a panacea for high blood pressure. While certain groups of older people with mildly high blood pressure showed signs of improvement after eating dark chocolate, the increase in calories is a deterrent for anyone looking to lose or maintain weight. Other studies showed that milk interfered with the absorption of the antioxidants in dark chocolate.
The health benefits of dark chocolate come from its content of cocoa phenols, which are natural compounds known for their antioxidant properties. As a general rule of thumb, WebMD recommends chocolate high in nonfat cocoa solids, which are higher in antioxidants. The highest amounts are found in natural cocoa powder, followed by unsweetened baking chocolate. Milk chocolate has the least amount of antioxidants.
However, WebMD does not recommend that people substitute healthy foods for dark chocolate, since most Americans consume plenty of sugar already. Instead, desserts and other types of chocolate should be replaced with dark chocolate for maximum health benefits.