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Bariatric surgery: Postoperative nutritional management

Robert F Kushner, MD
Susan Cummings, MS, RD
Daniel M Herron, MD, FACS, FASMBS
Section Editor
Daniel Jones, MD
Deputy Editor
Wenliang Chen, MD, PhD


The goals of bariatric operations include maximizing weight loss, and maintaining or achieving nutritional health, while preventing micronutrient deficiencies and lean body mass loss [1,2]. Bypass procedures include the Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion with duodenal switch (BPD-DS), and are known to cause micronutrient malabsorption [2-8].The sleeve gastrectomy (SG), which is the most commonly performed bariatric procedure in certain regions, does not involve intestinal bypass but can still lead to certain nutritional deficits. Since obesity is a risk factor of malnutrition and micronutrient deficiencies, all patients should be screened and deficiencies corrected prior to surgery.

The postoperative diet, micronutrient deficiencies, and nutritional management of the patient with obesity after bariatric surgery are reviewed here. Deficiencies of micronutrients following bariatric surgery can arise from several mechanisms that include preoperative deficiency, reduced dietary intake, malabsorption, and inadequate supplementation.

The specific bariatric procedures, indications, and outcomes are reviewed elsewhere and include the following topics:

(See "Bariatric procedures for the management of severe obesity: Descriptions".)

(See "Bariatric operations for management of obesity: Indications and preoperative preparation".)


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Literature review current through: Sep 2016. | This topic last updated: Aug 11, 2016.
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