Obesity is defined as having a high amount of body fat.
A person is obese if the fat weight in the body is more that 30 percent of their total weight. The most accurate way of measuring body fat is to weigh a person underwater or measure the person's skinfold fat using special calipers. Skinfold measurements are more practical and are available at most health clubs that have certified fitness instructors. As much as 50 to 75 percent of obesity has genetic influences. Just what those genetic influences are that affect body fat have not been identified.