- NICE uses 23 to define overweight and 27.5 to define obesity for these groups, instead of 25 and 30.
- The reason: type 2 diabetes and heart disease tend to develop at a lower BMI, often because more fat is stored around the organs.
- Eligibility thresholds for weight-management treatment are usually 2.5 points lower too.
Who the lower thresholds apply to
NICE recommends lower BMI thresholds for adults of South Asian (for example Indian, Pakistani, Bangladeshi or Sri Lankan), Chinese, other Asian, Middle Eastern, Black African and African-Caribbean family background. The guidance is about family background, not where you were born or live.
The numbers side by side
| Category | Standard BMI | Lower thresholds |
|---|---|---|
| Healthy weight | 18.5 – 24.9 | 18.5 – 22.9 |
| Overweight | 25 – 29.9 | 23 – 27.4 |
| Obesity | 30 and above | 27.5 and above |
Use our BMI calculator and tick the background box to see your result against the right thresholds.
Why risk starts earlier
Large studies have found that, at the same BMI, people from these backgrounds are more likely to develop type 2 diabetes, high blood pressure and heart disease — and often at a younger age. A key reason is body composition: more of the body’s fat tends to be stored inside the abdomen and around the liver, where it drives insulin resistance. Genetics and differences in muscle mass also play a part.
This is also why your waist-to-height ratio is so useful. Its 0.5 boundary applies to every ethnic group and picks up central fat directly.
What it means for treatment
Because risk starts earlier, eligibility for weight-management support is usually adjusted too. Where medical weight-loss treatment is generally considered from a BMI of 30 (or 27 with a weight-related condition), the equivalent thresholds for these groups are usually 27.5 (or 24.5 with a condition). Tell the prescriber about your family background during your assessment — including mixed heritage — so it can be taken into account.
Not sure if medical weight loss is right for you?
Our free online assessment takes about five minutes. A GPhC-registered prescriber reviews it and only recommends treatment if it is safe and suitable for you.
Start the free assessmentFrequently asked questions
I was born in the UK — do the lower thresholds still apply?
Yes. The thresholds relate to family background, not where you were born or where you live.
Does this apply to waist-to-height ratio?
No. The waist-to-height boundary of 0.5 applies to adults of every ethnic background.
Why does a health app show me a different category?
Many apps and older systems still use only the standard ranges. If the lower thresholds apply to you, your risk may be higher than the app suggests.
This page is general health information. It does not replace advice from your GP or another healthcare professional who knows your history. If you have symptoms that worry you, contact your GP or NHS 111; in an emergency call 999. Prescription treatment is only supplied after an assessment by a registered prescriber.