MEDICAL ANIMATION TRANSCRIPT: Obesity is a condition in which body weight is more than 20% above normal for age, height, and gender. While genetics play an important role in determining body weight, a properly balanced diet plays an important role in keeping weight under control and maintaining body function. The three main nutrients in a balanced diet are proteins, lipids, and carbohydrates. The recommended daily allowance of protein for a normal weight adult is 44 to 60 grams or approximately 20% of their caloric intake. Protein is needed for growth and development of muscle and for maintenance of tissue such as skin. The recommended daily allowance of lipids for a normal weight adult is 80 to 100 grams or approximately 30% of their caloric intake. Lipids have various functions, including energy storage in fat cells, vitamin absorption in the intestines, and composition of cellular structural components such as the phospholipid bilayer of the cell membrane. The recommended daily allowance of carbohydrates for a normal weight adult is 125 to 175 grams or approximately 50% of their caloric intake. Carbohydrates are used by the body primarily as fuel. They can be simple carbohydrates such as table sugar or corn syrup. Or they can be complex carbohydrates like pasta, vegetables, and whole wheat breads. Proteins, lipids, and carbohydrates compose nearly all dietary calories. Lipids are the most energy dense, containing more calories by weight than either proteins or carbohydrates. When the body has more calories than it needs to fuel its activities, it stores the excess as fat regardless of the source. Treatment of obesity must be addressed on an individual patient basis. However, some common treatments for obesity include diet and exercise, drug therapy such as orlistat, which blocks the absorption of fat, and surgical intervention such as gastric bypass and gastric banding.