Gastric bypass surgery may cause calcium and vitamin D deficiencies and bone loss, warn researchers.
Dr. Shonni J. Silverberg, professor of medicine at Columbia University College of Physicians and Surgeons, and colleagues studied 23 morbidly obese men and women who underwent gastric bypass surgery. Serum calcium, vitamin D, and parathyroid hormone levels, and bone mineral density were all measured before surgery and three, six, and twelve months afterwards. Results showed that within the twelve months following the procedure, participants lost an average 99 pounds; however they also exhibited significant declines in hip bone mineral density.
The authors conclude: “Following gastric bypass there was evidence of calcium and vitamin D malabsorption. Bone turnover increased and hip bone density rapidly declined. The decline in hip BMD was strongly associated with weight loss itself. Vigilance for nutritional deficiencies and bone loss in patients both before and after bariatric surgery is crucial.”
Fleischer J, Stein EM, Bessler M, Badia MD, Restuccia N, Olivero-Rivera L, McMahon DJ, Silverberg SJ. The decline in hip bone density following gastric bypass surgery is associated with extent of weight loss. J Clin Endocrinol Metab. Rapid Electronic Publication first published on Jul 22, 2008 as doi:10.1210/jc.2008-0481.
