Research

Hormonal

The exaggerated postprandial secretion of GLP-1 and PYY following Roux-en-Y gastric bypass (RYGB) and Vertical Sleeve Gastrectomy (VSG) contributes to improved glucose tolerance and insulin sensitivity, although its necessity is debated.

Surgery increases beneficial gut hormones like GLP-1, which help regulate blood sugar and appetite. While this is a key part of why surgery works, it is not the only factor, and the body's response varies by procedure.

GoodQualifiesMEDIUM confidence
It is widely accepted that postprandial circulating GLP-1 levels are markedly elevated after RYGB, BPD, and VSG... The physiological relevance of increased GLP-1 secretion in mediating glycemic improvements after RYGB and VSG is contentiously debated.
Rachel L. Batterham et al. · Diabetes Care · 2016

Why this rating

Based on multiple human and animal studies, though results are mixed regarding its necessity.

Source

Mechanisms of Diabetes Improvement Following Bariatric/Metabolic Surgery

Rachel L. Batterham et al. · Diabetes Care · 2016

DOI 10.2337/dc16-0145

narrative_reviewCited 371×
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DOI resolved against Crossref · corpus check 2026-06-10

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