The review of published studies notes that weight loss surgery can cause declines in bone mass and strength, and it is linked with an increased risk of bone fractures. Skeletal changes after surgery appear early and continue even after weight loss plateaus and weight stabilizes. Nutritional factors, mechanical unloading, hormonal factors, and changes in body composition and bone marrow fat may contribute to poor bone health.
Most studies have examined the effects of the Roux-en-Y gastric bypass procedure, which was the most commonly performed weight loss procedure worldwide until it was very recently overtaken by sleeve gastrectomy. Because sleeve gastrectomy is a newer procedure, its skeletal effects have not yet been well defined.
The review’s findings indicate that clinical guidelines on weight loss surgery should address bone health as a priority. “Current clinical guidelines do address bone health, but most recommendations are based on low-quality evidence or expert opinion,” said co-author Dr. Anne Schafer, of the University of California, San Francisco and the San Francisco VA Health Care System. “Future studies should address strategies to avoid long-term skeletal consequences of these otherwise beneficial procedures.”