Research

Hormonal

Gastric bypass surgery results in abnormally low plasma ghrelin levels and the loss of normal meal-related ghrelin fluctuations, which may contribute to sustained weight loss.

Gastric bypass surgery uniquely suppresses ghrelin, the hunger hormone, and eliminates its normal meal-time spikes. This hormonal suppression, rather than just stomach size reduction, helps explain why patients often feel less hungry and maintain weight loss better than with dieting alone.

GoodSupportsHIGH confidence
In contrast, despite a 36 percent weight loss after gastric bypass, the area under the curve for the ghrelin profile in the gastric-bypass group was 77 percent lower than in normal-weight controls (P<0.001)... The normal, meal-related fluctuations and diurnal rhythm of the ghrelin level were absent after gastric bypass.
David E. Cummings et al. · New England Journal of Medicine · 2002

Why this rating

Comparative study with matched controls and rigorous biochemical profiling.

Source

Plasma Ghrelin Levels after Diet-Induced Weight Loss or Gastric Bypass Surgery

David E. Cummings et al. · New England Journal of Medicine · 2002

DOI 10.1056/nejmoa012908

cohort · n=28Cited 2,233×
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DOI resolved against Crossref · corpus check 2026-06-10

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