What is BMI, how do you work it out, and how do you check your waist against your height?
"Too heavy or too thin may not be about the number on the scales." This Happy Series material from Herbalife Thailand introduces two numbers you can check at home: body mass index (BMI) and your waist measurement compared with your height.
What BMI is and how to work it out
- The material says keeping your weight within a suitable BMI range matters for overall health
- Formula: BMI = weight (kg) ÷ height (m) squared
- The suitable range for Thai adults is 18.5–22.9
Reading your BMI
- Below 18.5: underweight
- 18.5–22.9: normal
- 23–24.9: overweight
- 25–29.9: obesity, level 1
- 30 and above: obesity, level 2
What your BMI is useful for
- Understanding your own body shape and proportions
- Planning an exercise programme that suits you
- Its limits: athletes and people with a lot of muscle, or people retaining fluid, can have a high BMI without being overweight
Check belly fat with a tape measure
- Everyone's idea of a good figure is different, and some people who look slim may still carry fat around the abdomen
- The check in the material: if your waist measurement is more than half your height, that counts as abdominal obesity
- For anyone carrying a lot of abdominal fat, the material suggests learning more about food and exercising regularly
More images in this series (tap to enlarge)
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These numbers are a starting point for getting to know your body, not a diagnosis. Results may vary from person to person. If you have a health condition, are pregnant or take medication, consult a doctor before changing your diet or exercise. Ask us on LINE.
Image and reference from official material in the MyHerbalife media library: Happy Series – Knowledge 1 (social) · Happy Series – Knowledge 2 (social) (added to the library: Jul 2025)
Herbalife products are not intended to diagnose, treat, cure or prevent any disease.