Question 1

How is BMI calculated?

Accepted Answer

BMI (body mass index) is your weight in kilograms divided by your height in metres squared. Example: 89 kg / (1.72 m × 1.72 m) = BMI 30.1.

Question 2

What BMI counts as overweight and what as obesity?

Accepted Answer

BMI 25–29.9 is overweight; BMI 30 and above is obesity (class I 30–34.9, class II 35–39.9, class III 40+). Normal weight is BMI 18.5–24.9.

Question 3

From what BMI is medication considered in the Czech Republic?

Accepted Answer

Following expert guidelines, weight-loss medication is typically considered from BMI 30, or from BMI 27 with a weight-related condition such as high blood pressure, prediabetes or sleep apnoea. A doctor always makes the final decision.

Question 4

Is BMI accurate?

Accepted Answer

BMI is an approximate indicator – it does not account for muscle mass, age or fat distribution. Athletes with higher muscle mass can have a BMI in the overweight range. A medical examination and waist circumference give a fuller picture.

BMI	Category
below 18.5	Underweight
18.5 – 24.9	Normal weight
25 – 29.9	Overweight
30 – 34.9	Obesity class I
35 – 39.9	Obesity class II
40 and above	Obesity class III

BMI calculator

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