1. The Reality Check

BMI (Body Mass Index) is the most widely used health screening number in the world, printed on every medical chart — yet it's also one of the most misunderstood, since it was never designed to diagnose individual health.

2. Plain English Definition

BMI is a simple ratio of your weight to the square of your height, used as a quick population-level screening tool to flag possible weight-related health risks.

3. What BMI Actually Measures (and Doesn't)

BMI cannot distinguish between muscle and fat. A muscular athlete and a sedentary person of the same height and weight will show an identical BMI, despite having very different body compositions and health risk profiles. It's a starting point for a conversation, not a diagnosis.

4. Key Terms

• Underweight: BMI below 18.5
• Normal Weight: BMI 18.5–24.9
• Overweight: BMI 25–29.9
• Obese: BMI 30 and above

5. Next Steps

Calculate your BMI above, then consider pairing it with body fat percentage for a fuller picture of your health.