Understanding Your BMI Results
What the numbers mean, why context matters, and what to do next.
WHO Standard Categories
| BMI | Category | Risk |
|---|---|---|
| Below 18.5 | Underweight | Increased |
| 18.5 – 24.9 | Normal weight | Low |
| 25 – 29.9 | Overweight | Increased |
| 30 and above | Obese | High to very high |
Source: WHO Technical Report Series 894, 2000.
Why Indians and South Asians Use Different Thresholds
Research published in The Lancet (WHO Expert Consultation, 2004) found that South Asians develop type 2 diabetes and cardiovascular disease at lower BMI values than Europeans — due to higher visceral fat at any given BMI. The Indian Council of Medical Research (ICMR) endorses lower cut-offs for Indian adults.
| BMI | Asian Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 22.9 | Normal weight |
| 23 – 27.4 | Overweight |
| 27.5 and above | Obese |
Source: WHO Expert Consultation, The Lancet 2004; ICMR guidelines.
What BMI Cannot Tell You
BMI is a screening tool, not a diagnosis. It doesn't measure body fat directly and cannot distinguish muscle from fat. A professional athlete may score "overweight" while having excellent metabolic health.
- –Where fat is stored (visceral vs subcutaneous)
- –Muscle mass vs fat mass
- –Bone density
- –Cardiovascular fitness
- –Blood sugar, cholesterol, blood pressure
How to Improve Your Score
Underweight
Increase intake with nutrient-dense foods — nuts, legumes, whole grains. Strength training builds lean mass. See a doctor if you have unexplained weight loss.
Overweight / Obese
A 500 kcal/day deficit produces ~0.5 kg/week of loss (NHS). Prioritise whole foods, 150 min/week of moderate activity (WHO guidelines), and consistent sleep.
Always consult a registered doctor or dietitian before significant dietary changes.
References
- WHO. (2000). Obesity: preventing and managing the global epidemic. WHO Technical Report Series 894.
- WHO Expert Consultation. (2004). Appropriate body-mass index for Asian populations. The Lancet, 363(9403), 157–163.
- Keys, A. et al. (1972). Indices of relative weight and obesity. Journal of Chronic Diseases, 25, 329–343.
- NHS. (2023). What is the body mass index (BMI)? nhs.uk.
- Misra, A. et al. (2009). Consensus statement for diagnosis of obesity in Asian Indians. JAPI, 57, 163–170.