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What is BMI?
Body Mass Index (BMI) is a measure calculated from your height and weight. It is used worldwide as a screening tool to identify potential weight-related health risks. The formula is: BMI = weight (kg) ÷ height² (m²).
BMI Categories (WHO)
- Below 18.5 — Underweight
- 18.5 – 24.9 — Normal (healthy) weight
- 25.0 – 29.9 — Overweight
- 30.0 – 34.9 — Obese Class I
- 35.0 – 39.9 — Obese Class II
- 40.0 and above — Obese Class III (severe)
Limitations of BMI
BMI is a useful population-level screening tool but has important limitations. It does not directly measure body fat — athletes with high muscle mass may have a high BMI without excess fat. It also does not account for fat distribution (visceral fat around the abdomen is riskier than subcutaneous fat). Age, sex, and ethnicity affect what constitutes a healthy BMI. Always consult a healthcare professional for a comprehensive health assessment.