Research

Hormonal

Gastric bypass surgery increases postprandial PYY levels, which contributes to reduced food intake and weight loss.

Bariatric surgery works partly by changing how your gut hormones signal fullness. After surgery, your body releases more PYY, which helps you feel full faster and stay full longer, contributing to sustained weight loss beyond just having a smaller stomach.

GoodSupportsHIGH confidence
there is emerging evidence that PYY3-36 may partly mediate the reduced appetite and weight loss benefits observed post-gastric bypass surgery... patients who had undergone RYGBP had significantly higher meal-stimulated PYY levels compared with weight-matched controls or lean control subjects.
Efthimia Karra et al. · The Journal of Physiology · 2008

Why this rating

Multiple studies (Korner 2006, le Roux 2006) confirm elevated PYY post-surgery.

Source

The role of peptide YY in appetite regulation and obesity

Efthimia Karra et al. · The Journal of Physiology · 2008

DOI 10.1113/jphysiol.2008.164269

narrative_reviewCited 318×
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DOI resolved against Crossref · corpus check 2026-06-10

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