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Updated: Feb 19, 2026

Sleeve Gastrectomy in Mice using Surgical Clips
Published on: November 14, 2020
Vitamin D Metabolism in Bariatric Surgery
Marlene Chakhtoura1, Maya Rahme1, Ghada El-Hajj Fuleihan1
1Department of Internal Medicine, Division of Endocrinology, Calcium Metabolism and Osteoporosis Program, WHO Collaborating Center for Metabolic Bone Disorders, American University of Beirut Medical Center, Riad El Solh, Beirut, Lebanon.
Abstract:
Hypovitaminosis D is common in obese patients and persists after roux-en-Y gastric bypass and sleeve gastrectomy. Several societies recommend screening for vitamin D deficiency before bariatric surgery, and replacement doses of 3000 IU/d and up to 50,000 IU 1 to 3 times per week, in case of deficiency, with periodic monitoring. These regimens are mostly based on expert opinion. Large trials are needed to assess the vitamin D dose response, by type of bariatric surgery, and evaluate the effect on surrogate markers of skeletal outcomes. Such data are essential to derive desirable vitamin D levels in this population.
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