BMI (Body Mass Index) is the world's most widely used weight-health metric. But how accurate is it really? What are its blind spots? Let's settle it once and for all.
The BMI Formula
BMI = weight (kg) ÷ height² (m)
Example: 1.75 m tall, 70 kg → BMI = 70 ÷ (1.75 × 1.75) = 22.9
BMI Healthy Range Chart
| BMI range | Weight status | Health advice |
|---|---|---|
| < 18.5 | Underweight | Increase nutrient intake, build some muscle |
| 18.5 – 23.9 | Normal | Maintain your diet and exercise habits |
| 24 – 27.9 | Overweight | Control calorie intake, add cardio |
| ≥ 28 | Obese | Consider consulting a doctor or dietitian |
Limitations of BMI
BMI is convenient, but it has three clear blind spots:
- It doesn't distinguish muscle from fat: a bodybuilder can be "obese" by BMI while having very low body fat
- It ignores fat distribution: belly fat ("apple shape") is more harmful than hip/thigh fat ("pear shape")
- It doesn't fit special populations: pregnant women, children, and seniors have different fat standards
A More Complete Health Assessment
Pair BMI with these metrics:
- Use the calorie calculator to learn your daily calorie needs
- Use the calorie calculator to track exercise burn
- Measure your waist regularly (under 90 cm for men, 80 cm for women is healthy)
Head to the BMI calculator now and check where you stand.