Research

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Bariatric surgery significantly reduces the long-term incidence of type 2 diabetes in obese patients compared to usual care, with an adjusted hazard ratio of 0.17.

For severely obese individuals at high risk of diabetes, bariatric surgery is a highly effective preventive measure, far superior to lifestyle changes alone. While surgery carries small short-term risks, the long-term reduction in diabetes risk is substantial and sustained.

GoodSupportsHIGH confidence
During the follow-up period, type 2 diabetes developed in 392 participants in the control group and in 110 in the bariatric-surgery group, corresponding to incidence rates of 28.4 cases per 1000 person-years and 6.8 cases per 1000 person-years, respectively (adjusted hazard ratio with bariatric surgery, 0.17; 95% confidence interval, 0.13 to 0.21; P<0.001).
Lena Carlsson et al. · New England Journal of Medicine · 2012

Why this rating

Large prospective controlled study with long-term follow-up, though non-randomized.

Source

Bariatric Surgery and Prevention of Type 2 Diabetes in Swedish Obese Subjects

Lena Carlsson et al. · New England Journal of Medicine · 2012

DOI 10.1056/nejmoa1112082

cohort · n=3429Cited 786×
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DOI resolved against Crossref · corpus check 2026-06-10

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