Research

Hormonal

Unlike diet-induced weight loss, Roux-en-Y gastric bypass (RYGBP) does not trigger a compensatory increase in fasting ghrelin levels, thereby avoiding the hormonal drive for hunger typically associated with caloric restriction.

When you lose weight through dieting, your body naturally increases hunger hormones (ghrelin) to make you eat more. Roux-en-Y gastric bypass surgery avoids this biological backlash. Patients maintain lower levels of active ghrelin, meaning they do not experience the intense hunger spikes that often cause diet failures, making long-term weight maintenance easier.

GoodRefutesHIGH confidence
In summary, the absence of a compensatory increase in ghrelin concentrations that usually occurs with diet-induced weight loss... may contribute to weight loss and to the ability of an individual to maintain weight loss after this surgical procedure.
Judith Körner et al. · The Journal of Clinical Endocrinology & Metabolism · 2005

Why this rating

Clear statistical difference in fasting octanoylated ghrelin between groups.

Source

Effects of Roux-en-Y Gastric Bypass Surgery on Fasting and Postprandial Concentrations of Plasma Ghrelin, Peptide YY, and Insulin

Judith Körner et al. · The Journal of Clinical Endocrinology & Metabolism · 2005

DOI 10.1210/jc.2004-1076

cross_sectional · n=32Cited 419×
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DOI resolved against Crossref · corpus check 2026-06-10

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