Research

Hormonal

Roux-en-Y gastric bypass (RYGB) surgery restores gut hormone balance by elevating postprandial GLP-1 and PYY levels, which contributes to sustained weight loss and improved glucose homeostasis.

For patients who have undergone Roux-en-Y gastric bypass, the surgery works largely by changing how gut hormones signal fullness (GLP-1 and PYY). This hormonal shift helps maintain weight loss and improves blood sugar control long-term. If surgery is not an option, new combination drug therapies aim to replicate this hormonal effect.

GoodSupportsHIGH confidence
Indeed, the reported weight loss with ensuing improvement in glucose homeostasis in patients undergoing RYGB surgery or sleeve gastrectomy is associated with elevated postprandial PYY and GLP-1 levels, even one year after surgery [136,137].
Mona Farhadipour et al. · Nutrients · 2021

Why this rating

Based on multiple cited studies showing consistent elevation of satiety hormones post-surgery, though ghrelin effects are inconsistent.

Source

The Function of Gastrointestinal Hormones in Obesity—Implications for the Regulation of Energy Intake

Mona Farhadipour et al. · Nutrients · 2021

DOI 10.3390/nu13061839

narrative_reviewCited 55×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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