Weight-loss (bariatric) surgery helps you lose weight and lowers your risk of medical problems associated with obesity. Bariatric surgery contributes to weight loss in two main ways:
- Restriction. Surgery is used to physically limit the amount of food the stomach can hold, which limits the number of calories you can eat.
- Malabsorption. Surgery is used to shorten or bypass part of the small intestine, which reduces the amount of calories and nutrients the body absorbs.