BMI plus waist risk explainer

BMI says how much you weigh for your height. Your waist says where it sits. Together they give a clearer picture than either one alone.

Your details

Sex
Weight
Height
Waist

Measure your waist halfway between your lowest rib and the top of your hip bone, breathing out normally.

Your combined risk

High risk

BMI 27.2 with a very high waist

  • BMI27.2, overweight
  • Waist bandVery high
  • Waist to height0.52

This is a measure of risk of conditions like type 2 diabetes and heart disease, not a diagnosis. A GP or practice nurse can check what is really going on.

The table

How the two numbers combine

Until 2025, NICE guideline CG189 used this table to sort health risk for adults with a BMI of 25 or more. It is still used in many GP surgeries.

BMILow waistHigh waistVery high waist
25 to 29.9No increased riskIncreasedHigh
30 to 34.9IncreasedHighVery high
35 and overVery highVery highVery high

For men, a low waist is under 94 cm (37 in), high is 94 to 102 cm and very high is over 102 cm (40 in). For women the lines are 80 cm (31.5 in) and 88 cm (34.6 in).

What changed

Waist to height is the new favourite

The 2025 guideline, NG246, now prefers the waist to height ratio, because it works for every height and background. So we show that too. A ratio under 0.5 means no increased risk, whatever your BMI says.

Read with care

What this cannot tell you

  • Risk is not a diagnosisIt describes the chance of conditions like type 2 diabetes, not whether you have them.
  • Very high BMIFrom a BMI of 35, NICE says waist measurements add little.
  • BloatingA big meal or period bloating can add an inch for a day.

Questions

Common questions

Is waist size more important than BMI?

They measure different things. Fat around the middle is more closely linked to type 2 diabetes and heart disease, which is why NICE now asks for a waist check alongside BMI.

What waist size is high risk for a man?

Over 102 cm (40 in) is classed as very high risk on the old NICE table. Over 94 cm (37 in) counts as high.

I am overweight but my waist is low. Is that OK?

On the NICE table, an overweight BMI with a low waist means no increased risk. It often points to a sturdier build or more muscle.

Sources

Last checked 21 October 2026. Spotted something wrong? Tell us and we will fix it.

If your weight is on your mind

Talk to your GP if your weight has changed a lot without trying, or if it is worrying you. If food or your body feels hard to think about, Beat has a free helpline on 0808 801 0677 (England, weekdays 3pm to 8pm).

Related

Related calculators