Research

Hormonal

Gastric bypass surgery (GBP) improves glucose metabolism and reduces obesity risk partly by altering gut microbiota composition and increasing the secretion of gut hormones (GLP-1, PYY), often before significant weight loss occurs.

Gastric bypass surgery reverses type 2 diabetes and improves metabolic health rapidly, often before significant weight loss. This is driven by anatomical changes that increase beneficial gut hormones (GLP-1, PYY) and alter gut bacteria. It is a highly effective intervention for severe obesity and diabetes.

GoodSupportsHIGH confidence
weight loss following bariatric surgery in morbidly obese patients with type 2 diabetes leads to a rapid reversal of the pathophysiology and subsequent resolution of diabetes mellitus... this glycaemic improvement actually occurs before weight loss... Several studies have reported an increase in postprandial plasma levels of PYY and/or GLP-1 as early as 2 days after bypass.
A. Vrieze et al. · Diabetologia · 2010

Why this rating

Strong clinical evidence from human studies showing rapid metabolic improvement post-surgery, supported by mechanistic animal/human data on hormones and microbiota.

Source

The environment within: how gut microbiota may influence metabolism and body composition

A. Vrieze et al. · Diabetologia · 2010

DOI 10.1007/s00125-010-1662-7

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DOI resolved against Crossref · corpus check 2026-06-10

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