Question 1

Why are there two sets of thresholds?

Accepted Answer

The WHO figures (25 overweight, 30 obese) were derived largely from European populations. Research in East and South Asia found that health risks such as type 2 diabetes appear at a lower BMI, so China uses 24 and 28. If you are of Asian descent, the stricter set is usually the more relevant one.

Question 2

Is BMI reliable for athletes?

Accepted Answer

No. Muscle is denser than fat, so a lean, muscular person can land in the overweight or even obese range while carrying very little fat. Waist circumference or a body-composition measurement is more informative in that case.

Question 3

What is a healthy weight for my height?

Accepted Answer

The range shown above corresponds to a BMI of 18.5 to 24.9 for your height. It is a range rather than a single number because a healthy weight depends on build, muscle mass and other factors.