Research

Energy balance

Maintaining a body-mass index (BMI) between 19 and 25 is associated with the lowest mortality rates and reduced risk of chronic diseases, whereas weight gain during adulthood significantly increases the risk of type 2 diabetes, hypertension, and coronary heart disease.

Aim to keep your BMI between 19 and 25. Do not accept gradual weight gain as 'normal' aging. If you gain 10 pounds after reaching adult height, intervene immediately with diet and activity changes to prevent long-term metabolic damage.

StrongSupportsVERY_HIGH confidence
For persons younger than 75, total mortality rates were 8 to 35 percent higher among those with body-mass indexes of 25 to 26.9 and 18 to 40 percent higher among those with body-mass indexes of 27.0 to 28.9 than among persons with body-mass indexes of 19 to 21.9.
Walter C. Willett et al. · New England Journal of Medicine · 1999

Why this rating

Based on large prospective cohort studies (Nurses' Health Study, Health Professionals Follow-up Study, American Cancer Society cohort) with rigorous controls for smoking and reverse causation.

Source

Guidelines for Healthy Weight

Walter C. Willett et al. · New England Journal of Medicine · 1999

DOI 10.1056/nejm199908053410607

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DOI resolved against Crossref · corpus check 2026-06-10

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