Research

Energy balance

For healthy, never-smoking adults, the optimal body-mass index (BMI) for longevity is 23.5–24.9 for men and 22.0–23.4 for women, with mortality risk increasing linearly as BMI rises above these ranges.

If you are a healthy adult who has never smoked, aim for a BMI between 23.5 and 24.9 (men) or 22.0 and 23.4 (women) to minimize mortality risk. Avoiding overweight and obesity is critical for longevity, regardless of age, as higher BMI consistently increases absolute death risk.

StrongSupportsVERY_HIGH confidence
In healthy people who had never smoked, the nadir of the curve for body-mass index and mortality was found at a body-mass index of 23.5 to 24.9 in men and 22.0 to 23.4 in women.
Eugenia E. Calle et al. · New England Journal of Medicine · 1999

Why this rating

Large prospective cohort (n>1 million), long follow-up (14 years), rigorous exclusion of confounders (smoking, disease).

Source

Body-Mass Index and Mortality in a Prospective Cohort of U.S. Adults

Eugenia E. Calle et al. · New England Journal of Medicine · 1999

DOI 10.1056/nejm199910073411501

cohort · n=1046154Cited 3,663×
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DOI resolved against Crossref · corpus check 2026-06-10

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