Weight-loss Surgery Side Effects

What are the side effects of bariatric surgery?

Side effects of weight-loss surgery, also called metabolic and bariatric surgery, may include

Follow-up interventions, surgery, and hospitalizations are relatively common within 5 years of weight-loss surgery, affecting about one-third of patients. Follow-up procedures are required more frequently after gastric bypass compared with gastric sleeve.9

Rarely, surgery-related problems can lead to death.

Other side effects may occur later. Your body may not absorb enough nutrients, especially if you don’t take your prescribed vitamins and minerals. Not getting enough nutrients can cause health problems, such as anemia and osteoporosis. Gallstones can occur after rapid weight loss. Some health care professionals prescribe medicine for about 6 months after surgery to help prevent gallstones. Gastric bands can move out of position or erode into the stomach wall and need to be removed.

A hand holding several nutritional supplements.
Taking your prescribed vitamins and minerals will help you get the nutrients you need.

Other problems that could occur later include strictures and hernias. Strictures—narrowing of the new stomach or the connection between the stomach and small intestine—make it hard to eat solid food and can cause nausea, vomiting, and trouble swallowing. Health care professionals treat strictures with special instruments to expand the narrowing. Two kinds of hernias may occur after weight-loss surgery—at the incision site or in the abdomen. Hernias can be repaired with surgery.

Some research suggests that weight-loss surgery, especially gastric bypass, may change the way your body absorbs and breaks down alcohol and may lead to more alcohol-related problems after surgery.


Last Reviewed September 2020
Share this page
Facebook X Email WhatsApp LinkedIn Reddit Pinterest

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. NIDDK translates and disseminates research findings to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by NIDDK is carefully reviewed by NIDDK scientists and other experts.