If you are South Asian or Indian, the standard BMI chart probably understates your health risk. The usual World Health Organization cut-offs - overweight at a BMI of 25 and obese at 30 - were calibrated mainly on White European populations, and they let too much risk slip through for people of South Asian descent.
You should use lower thresholds. For South Asians, risk starts climbing at a BMI of 23, and India's 2025 guidelines now treat any BMI above 23 as the entry point for obesity assessment. The lower cut-offs began with the WHO 2004 expert consultation published in The Lancet. In January 2025, Indian experts from AIIMS, Fortis C-DOC and N-DOC went further and formally redefined obesity for Asian Indians, the first update in 15 years. The reason is simple but important. South Asians develop type 2 diabetes and heart disease at a lower body weight than the standard chart assumes.
By the Smart Health Calculators editorial team. Last updated 4 June 2026. This article is educational and is not a medical diagnosis. Sources are listed at the end.
Key takeaways
- Use lower cut-offs. For South Asians, risk begins at a BMI of 23, not 25. Under India's 2025 revised definition, a BMI above 23 is already the starting point for obesity assessment.
- Same BMI, more fat. At an identical BMI, South Asians carry more total body fat and more visceral fat around the organs than White Europeans.
- The "thin-fat" phenotype is real. Many South Asians look slim and sit in the normal BMI range while being metabolically overweight - sometimes called normal-weight obesity.
- Risk climbs earlier. Type 2 diabetes, insulin resistance, and heart disease appear at lower BMI levels in South Asians than in most other groups.
- Measure more than BMI. Track waist circumference, waist-to-height ratio, and body fat percentage - they capture central fat that BMI misses.
Why doesn't standard BMI work for Indians?
BMI is just weight divided by height squared. It says nothing about how much of your weight is fat, where that fat sits, or how much muscle you carry. That is a problem for everyone, but it is a bigger problem for South Asians because of a consistent difference in body composition.
At any given BMI, people of South Asian origin tend to have a higher percentage of body fat and more abdominal, visceral fat than White Europeans, alongside relatively lower muscle mass. So an Indian man with a BMI of 24 - comfortably "normal" on the standard chart - may carry the fat profile and metabolic risk that the chart only expects at a BMI of 27 or 28.
This was the core finding behind the WHO 2004 expert consultation in The Lancet , which concluded that the health risks of Asian populations rise from a lower BMI than the standard thresholds suggest. The result is a real risk of under-diagnosis if you read your number against the wrong chart. We cover the general limits of the metric in our guide to why BMI is inaccurate.
What are the BMI cut-offs for South Asians?
The WHO recommended adding lower "action points" for Asian populations rather than replacing the international classification entirely. In practice, that means reading your BMI against a shifted scale. India's revised obesity guidelines, including those informed by the ICMR, follow a similar pattern.
| Category | Standard WHO BMI | Asian / South Asian BMI |
|---|---|---|
| Underweight | Below 18.5 | Below 18.5 |
| Normal weight | 18.5–24.9 | 18.5–22.9 |
| Overweight / increased risk | 25–29.9 | 23–27.4 |
| Obese / high risk | 30 and above | 27.5 and above |
These are the WHO 2004 screening action points. A BMI of 23 marks the point where risk begins to climb, and 27.5 is the higher action point where many clinicians recommend active intervention. They are screening thresholds, not a diagnosis. India's own guidance has since moved further, which is covered in the 2025 update below. If you want the general-population view for comparison, see our explainer on what is a healthy BMI.
The formula itself does not change. Our Indian BMI Calculator does the interpreting for you, reading your result against the lower Asian thresholds above rather than the default chart. You can also use the standard BMI Calculator for the raw figure.
India redefined obesity in 2025: stages, not just BMI
In January 2025, the National Diabetes Obesity and Cholesterol Foundation, Fortis C-DOC and AIIMS published a revised definition of obesity for Asian Indians , the first update since 2009, in step with the global Lancet Commission on clinical obesity. The biggest change is that BMI alone no longer decides whether you are obese. It only decides whether you should look closer.
- Stage 1 obesity. A BMI above 23 with no effect yet on organ function or daily activities. This is the warning stage. The goal is to act before it progresses.
- Stage 2 obesity. A BMI above 23 combined with a large waist (over about 90 cm for men, 80 cm for women) or a high waist-to-height ratio, plus at least one obesity-related condition such as type 2 diabetes or knee pain that limits daily activity. This stage calls for active medical management.
Within these stages, BMI is still graded: 23 to 24.9 is Grade I, 25 to 27.5 is Grade II, 27.6 to 32.4 is Grade III and 32.5 or above is Grade IV. The practical takeaway is simple. BMI gets you in the door at 23. Your waist and your health effects decide how serious it is.
A worked example. An Indian man who is 5'8" (173 cm) and weighs 72 kg has a BMI of about 24.1. The standard chart calls that normal. Under the 2025 Indian definition he is already in Stage 1 territory, and if his waist measures over 90 cm and his blood sugar is high, he meets the criteria for Stage 2. Same body, very different message.
What is the "thin-fat" Indian phenotype?
The "thin-fat" phenotype describes a body that looks slim on the outside but carries a high proportion of fat on the inside - particularly around the abdomen and internal organs - with comparatively little muscle. It is also called the normal-weight-obese phenotype, because the BMI reads as normal while the body composition does not.
This pattern has been observed from birth in South Asian populations: studies describe Indian newborns as relatively low in weight but high in body fat compared with European babies. Across a lifetime, that tendency to store fat centrally rather than build muscle helps explain why diabetes and heart disease appear so early and at such low body weights in this group.
The practical message is uncomfortable but useful: a flat or slim-looking frame does not guarantee you are metabolically healthy. A normal BMI in a South Asian body can still hide a high-risk fat distribution.
Why visceral fat matters more here
Visceral fat is the fat packed around your liver, pancreas, and intestines. It is far more metabolically active - and more dangerous - than the subcutaneous fat under your skin. It drives insulin resistance, inflammation, and abnormal blood lipids.
Research consistently shows South Asians carry more visceral fat than other groups at the same BMI and the same waist size, which is a major reason their risk of type 2 diabetes and cardiovascular disease is elevated . That is fat BMI can never see, which is why no single number from a height and weight ratio can settle the question on its own.
What should you track instead of BMI?
BMI is still a fine starting point - quick, free, and directionally useful when read against the right chart. But for South Asians especially, it should be one number among several. The most useful additions all capture central fat.
Waist circumference
Because South Asians store fat centrally, waist size is one of the most telling measurements you can take. Indian guidelines use lower cut-offs than Western ones - abdominal obesity is often flagged at a waist of around 90 cm for men and 80 cm for women, compared with roughly 102 cm and 88 cm in standard Western thresholds.
Waist-to-height ratio
Dividing your waist by your height accounts for body size and is a strong, simple predictor of cardiometabolic risk. A common rule of thumb is to keep your waist below half your height - a ratio under 0.5.
Body fat percentage
Since the South Asian issue is fundamentally about fat versus muscle, an actual body fat estimate is valuable. Our Body Fat Calculator uses the Navy method, which incorporates your waist measurement and therefore captures some of the central-fat signal that BMI ignores.
Blood markers and fitness
Fasting blood glucose, HbA1c, blood pressure, and a lipid panel say far more about your metabolic health than any single body measurement. Given the early onset of diabetes in South Asians, screening earlier and more often is a reasonable, evidence-based precaution to raise with your doctor.
Putting it together
If you are South Asian or Indian, treat a BMI of 23 as your watch line rather than waiting for 25 or 30. Under India's 2025 definition that is already the entry point for obesity assessment. Pair that number with a waist measurement and, ideally, an occasional check of your blood glucose and blood pressure. None of this is cause for alarm - it is simply a more accurate frame for a body type the standard chart was never built around.
The goal is not to fixate on a lower number. It is to make sure the number you do use is telling you the truth. For South Asians, the standard BMI chart often does not - and a small adjustment to the thresholds, plus a tape measure, closes most of that gap.
Frequently asked questions
What is a healthy BMI for South Asians and Indians?
Generally below 23. Risk starts climbing at a BMI of 23, which is also where India's 2025 guidelines begin obesity assessment. The standard cut-offs of 25 and 30 are set too high for South Asian bodies.
Why are BMI cut-offs lower for Indians?
Because South Asians carry more body fat and more visceral fat at the same BMI than White Europeans. This raises their risk of type 2 diabetes and heart disease at a lower body weight, so a lower threshold flags risk earlier.
What is the thin-fat or normal-weight-obese phenotype?
It describes South Asians who look slim and have a normal BMI but carry a high proportion of body fat, especially around the abdomen and organs, with relatively low muscle mass. It is linked to higher metabolic risk.
At what BMI is an Indian considered obese?
Under India's 2025 revised definition, obesity assessment starts at a BMI above 23. A BMI above 23 with no effect on organs or daily life is Stage 1 obesity. It becomes Stage 2 when combined with a large waist or high waist-to-height ratio plus a related condition or physical limitation. The older WHO Asian action points used 27.5 as the high-risk threshold.
Should South Asians measure waist circumference too?
Yes. Because South Asians store more fat centrally, waist circumference and waist-to-height ratio are especially useful. Indian guidelines often use a lower waist cut-off of around 90 cm for men and 80 cm for women.
Does the BMI calculator change for Indians?
The formula stays the same - weight in kilograms divided by height in metres squared. What changes is interpretation. Read the result against the lower Asian cut-offs rather than the standard chart.
Sources
- WHO Expert Consultation. Appropriate body-mass index for Asian populations. The Lancet, 2004.
- Misra A, et al. Revised definition of obesity in Asian Indians living in India. Diabetes & Metabolic Syndrome: Clinical Research & Reviews, 2025.
- Research on visceral fat and cardiometabolic risk in South Asians.
This article is for education only and does not replace advice from a qualified doctor. If your numbers fall in the ranges discussed here, the right next step is a conversation with a healthcare professional.