Unless there is a disorder of body structure, body type is genetic. Most people evaluate their body weight based on their body type. For example, a person whose body mass index is at a normal level (e.g. BMI 23) may seem overweight because of regional fat accumulation. On the other hand, a person whose BMI is 28, even though it is overweight level, may seem normal weight because of stable fat accumulation. The body type is especially noticeable in obese people. The sagging after bariatric surgery depends on the body type. If you have a triangle body type, there is usually not too much sagging in your body. On the other hand, if you have an apple body type, there is usually sagging in your body.