Health
BMI Explained: What Your Number Really Means
What is BMI?
Body Mass Index (BMI) is a number calculated from your weight and height. It's a screening tool, not a diagnosis.
BMI = weight (kg) / [height (m)]²
WHO categories
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Normal weight |
| 25 to 29.9 | Overweight |
| 30+ | Obese |
Where BMI falls short
- It doesn't distinguish muscle from fat, bodybuilders score "overweight"
- It doesn't account for fat distribution (visceral fat matters more)
- It's less reliable for the elderly, very tall, or very short people
Better complements to BMI
- Waist-to-hip ratio
- Body fat percentage (DEXA, calipers, or smart scale)
- Resting heart rate and blood pressure
Check yours instantly with our BMI Calculator.
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