Superfoods are not a separate category, according to the American Heart Association. This is a marketing term used to describe foods that contain a huge amount of nutrients, few calories, little or no sugar and salt, fiber and other health boosters.  Most definitions will describe them as being rich sources of antioxidants, which protect our body cells from damaging, thus preventing illnesses, and in nutrients lowering bad cholesterol and the risk of heart problems, cancer and other diseases. Some foods have the power to improve mood, energy, metabolism and vision even when you consume them in small doses. Others are especially helpful in achieving weight loss goals during the summer.