Surgery on the stomach and/or intestines to help a person with extreme obesity lose weight. Bariatric surgery is an option for people who have a body mass index (BMI) above 40. Surgery is also an option for people with a body mass index between 35 and 40 who have health problems like type 2 diabetes or heart disease.
There are two basic types of bariatric surgery — restrictive surgeries and malabsorptive/restrictive surgeries. Restrictive surgeries work by physically restricting the size of the stomach and slowing down digestion. Malabsorptive/restrictive surgeries are more invasive surgeries that, in addition to restricting the size of the stomach, physically remove parts of the digestive tract, interfering with absorption of calories.