Substituting a cup of cocoa throughout the day for other snacks could help obese people lose weight – even if they're on a high-fat diet, a new study claims. In lab experiments, US researchers gave obese mice with liver disease a dietary supplement of cocoa powder, for a period of eight weeks. Even though the mice were on a high-fat diet, the experts found the supplement reduced DNA damage and the amount of fat in their livers. While there is more to learn about the health benefits of cocoa, the researchers believe it may in some way impede the digestion of dietary fat and carbohydrate, thereby avoiding weight gain.