What is BMI?
Body Mass Index (BMI) is a simple numerical value calculated from your height and weight that classifies your body weight relative to your height. It is widely used as a screening tool to identify weight categories that may lead to health problems.
BMI Categories (WHO Standard)
🔵
Under 18.5
Underweight
🟢
18.5 – 24.9
Normal Weight
🟡
25.0 – 29.9
Overweight
🔴
30.0 and above
Obese
Limitations of BMI
BMI is a useful screening tool but has limitations: it does not account for muscle mass (athletes may have high BMI but low body fat), bone density, age-related body changes, or fat distribution. For a complete health assessment, consult a healthcare professional.
Is a BMI of 25 always unhealthy?
Not necessarily. BMI of 25-27 may be acceptable for older adults and those with high muscle mass. Context matters — age, fitness level and waist circumference should also be considered.
Does BMI differ by ethnicity?
Yes. Asian populations have higher health risks at lower BMI values. WHO recommends Asian-specific cutoffs: Overweight at BMI ≥23 and Obese at BMI ≥27.5.
What is a healthy BMI for children?
For children (2-18), BMI is interpreted using age and gender-specific percentile charts, not the adult categories. A pediatrician should interpret children's BMI results.