he set-point theory proposes that humans have a genetically predetermined body weight or body fat content, which the body closely regulates. Research suggests that genes account for up to of weight differences between people. The genes may be those that determine body type, metabolic rate, and the factors that affect hunger and satiety. People who experience significant are members of a cultural or ethnic group that prefers body weight, have a social network of friends, or get insufficient sleep are likely to carry excess body fat. Those with limited incomes tend to have a risk of obesity