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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]. Deficiencies of micronutrients following bariatric surgery can arise from several mechanisms that include preoperative deficiency, reduced dietary intake, malabsorption, and inadequate supplementation. 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 and texture progression, micronutrient deficiencies, and their management are reviewed here.

Bypass procedures, such as Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion with duodenal switch (BPD/DS), 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. Any bariatric procedure can result in malnutrition if a proper diet is not followed. 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".)

(See "Bariatric operations: Perioperative morbidity and mortality".)

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Literature review current through: Sep 2017. | This topic last updated: Oct 10, 2017.
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