BMI & waist-to-height ratio
Body mass index (BMI) with WHO categories and the lower cut-offs suggested for Asian populations, plus waist-to-height ratio (WHtR) as an indicator of central adiposity.
Inputs
Results
BMI
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Waist-to-height ratio
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The formula
BMI = mass(kg) ÷ height(m)²
WHtR = waist circumference ÷ height (same units)
WHtR = waist circumference ÷ height (same units)
Limitations
- BMI does not distinguish fat from muscle; muscular athletes can be misclassified.
- BMI does not show where fat is stored; central (abdominal) fat carries more cardiometabolic risk — WHtR helps here.
- Risk at a given BMI differs between ethnic groups; many Asian populations show higher risk at lower BMI.
- Neither measure is valid for children (use age-specific charts), pregnancy or some medical conditions.
Important
These are screening indicators for education, not diagnoses. Discuss results and any health concerns with a qualified health professional.
Sources
- WHO Expert Consultation (2004). Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet 363(9403):157–163.
- Ashwell M, Gunn P, Gibson S (2012). Waist-to-height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta-analysis. Obes Rev 13(3):275–286.