You visit your doctor. She checks your BMI and says you are overweight. You come home, enter the same numbers into a fitness app, and it tells you your weight is perfectly normal. Both cannot be right — but they are using different charts. This is not a calculation error. It is a deliberate difference that reflects decades of medical research into how Indian bodies actually work.
The Indian Council of Medical Research (ICMR) recommends that Indians be classified as overweight from a BMI of 23.0, not 25.0 as the World Health Organization's global standard states. That two-point gap has significant consequences for how millions of Indians understand their own health risk.
What Is BMI and How Is It Calculated?
Body Mass Index is a simple ratio: your weight in kilograms divided by the square of your height in metres. A person who weighs 70 kg and stands 170 cm tall has a BMI of 24.2. The formula itself is identical worldwide — what differs is the threshold at which each category begins.
BMI was never designed to be a direct measure of body fat or health. It is a population-level screening tool — useful for identifying broad patterns across large groups of people, not for diagnosing an individual's health. Its value is in what the categories tell you: above a certain BMI threshold, studies consistently show higher rates of type 2 diabetes, hypertension, and cardiovascular disease. The question is: what is that threshold for Indians?
Who the Original BMI Charts Were Built For
The WHO's BMI classification — widely reproduced in health apps, school charts, and fitness trackers — was derived primarily from studies conducted on European and North American populations. The thresholds of 25.0 for overweight and 30.0 for obese reflect the body composition and metabolic risk profile of those populations.
For many decades, these same thresholds were applied globally, including in India. The problem: the relationship between BMI and body fat percentage, and between body fat percentage and disease risk, is not the same across all ethnic groups. Using a chart built for European bodies to assess the health risk of an Indian body is like using the wrong reference range for a blood test — the number looks fine, but the interpretation is wrong.
Why Indian Bodies Are Biologically Different at the Same BMI
Research comparing body composition across ethnic groups has consistently found that South Asian populations, including Indians, carry a higher proportion of body fat at the same BMI compared to many Western populations. Studies show this difference is in the range of 3–5 percentage points of body fat at equivalent BMI values, with Indians typically ranking highest in body fat percentage among compared Asian subgroups.
More importantly, this excess fat is concentrated in the wrong place. Indians disproportionately store visceral fat — fat packed around internal organs such as the liver, pancreas, and intestines — rather than subcutaneous fat stored under the skin. Visceral fat is metabolically active in a harmful way. It drives insulin resistance, raises blood glucose, elevates triglycerides, and promotes inflammation. The result is that metabolic damage begins accumulating at lower body weights in Indians than in populations with different fat distribution patterns.
A Lancet Diabetes & Endocrinology study examining type 2 diabetes risk across ethnicities found that South Asian populations reached a 10-year risk of developing type 2 diabetes equivalent to that seen in white Europeans at a BMI roughly 4–5 points lower. In other words, the metabolic risk that a BMI of 27 signals in a white European may already be present at a BMI of 22–23 in an Indian adult.
Check your BMI using Indian ICMR standards — not the Western chart
Use the BMI Calculator →ICMR vs WHO — The Exact Numbers
Here is how the two classification systems compare side by side:
| BMI Range | ICMR Classification (Indian Standard) | WHO Classification (Global Standard) |
|---|---|---|
| Below 18.5 | Underweight | Underweight |
| 18.5 – 22.9 | Normal Weight | Normal Weight |
| 23.0 – 24.9 | Overweight | Normal Weight |
| 25.0 – 29.9 | Obese | Overweight |
| 30.0 and above | Obese | Obese |
The practical consequence: a person with a BMI of 24.0 is classified as "Normal Weight" by WHO standards and "Overweight" by ICMR standards. A person with a BMI of 27.0 is "Overweight" by WHO and "Obese" by ICMR. These are not minor semantic differences — the ICMR classification may prompt earlier screening, earlier lifestyle intervention, and earlier treatment that can prevent progression to type 2 diabetes or cardiovascular disease.
The Real-World Impact for Indian Adults
India has an estimated 101 million people living with diabetes, according to the ICMR-INDIAB national study published in The Lancet Diabetes & Endocrinology in 2023 — the most comprehensive nationally representative data available. India has the second-highest number of people with diabetes in the world, after China.
A significant portion of this burden is driven by people who were never identified as at-risk because their BMI appeared normal on a Western chart. Using ICMR thresholds, which classify overweight from BMI 23, catches a larger proportion of at-risk Indians earlier — when interventions like dietary change, increased physical activity, and weight management are most effective at preventing progression to full diabetes.
Waist circumference adds another dimension. Indian guidelines recommend a waist of less than 90 cm for men and less than 80 cm for women — both lower than the WHO's corresponding thresholds of 94 cm and 80 cm. This is because abdominal fat accumulation, even at normal BMI, is a stronger predictor of metabolic risk in Indian adults. A person can have a BMI of 22 and a waist of 92 cm — technically "normal weight" but with significant abdominal adiposity and elevated risk.
What to Do With Your BMI Result
BMI is a starting point, not a diagnosis. Here is how to interpret your result using ICMR thresholds:
- BMI below 18.5 (Underweight): May indicate nutritional deficiency, a thyroid condition, or other underlying causes. A basic blood panel can help identify the reason. Speak with your doctor.
- BMI 18.5–22.9 (Normal Weight): Healthy range for Indian adults. Check your waist circumference — even at normal BMI, abdominal fat above the Indian thresholds warrants attention.
- BMI 23.0–24.9 (Overweight by ICMR): Ask your doctor for a fasting blood glucose test or HbA1c to screen for pre-diabetes. This is the window where lifestyle changes are most effective.
- BMI 25.0 and above (Obese by ICMR): Elevated risk of type 2 diabetes, hypertension, and cardiovascular disease. A full metabolic panel — blood sugar, lipids, blood pressure — is recommended.
Athletes, bodybuilders, and people with high muscle mass may show elevated BMI without elevated health risk, as muscle weighs more than fat. Conversely, the "thin-fat Indian" — normal BMI, high abdominal fat, low muscle — may carry significant hidden metabolic risk. If in doubt, your doctor can assess the full picture, including waist circumference, body composition, and blood markers.
You can also read more in our companion article: Why BMI Is Not Accurate For Indians — And What To Use Instead.
Frequently Asked Questions
Why is the Indian BMI standard different from the WHO standard?
Indians carry 3–5% more body fat at the same BMI compared to many Western populations, concentrated in the abdomen around internal organs. This higher visceral fat accumulation is associated with greater risk of type 2 diabetes, hypertension, and heart disease even at lower body weights. The Indian Council of Medical Research (ICMR) therefore recommends a lower overweight threshold of 23.0 instead of the WHO's 25.0 to better reflect actual risk in Indian adults.
What is the normal BMI range for Indian adults?
According to ICMR guidelines (Misra A et al, JAPI 2009), a BMI between 18.5 and 22.9 is the healthy range for Indian adults. A BMI of 23.0–24.9 is overweight, and 25.0 or above is obese by Indian standards. This is different from the WHO global thresholds of 25.0 for overweight and 30.0 for obese.
Should Indians use the Western BMI chart?
No. Western BMI charts were developed from studies conducted primarily on European populations and systematically underestimate health risk in Indian adults. Indian doctors and ICMR guidelines use lower thresholds — overweight from BMI 23, obese from BMI 25 — because these better reflect when metabolic risk actually begins to rise in Indian bodies. Using a Western chart to interpret an Indian's BMI can create a false sense of reassurance.
Can I have a normal BMI but still be at risk?
Yes — this is known as the "thin-fat Indian" phenomenon. A person with a BMI in the normal range (18.5–22.9) can still carry significant visceral fat around abdominal organs, particularly if their waist circumference exceeds the Indian thresholds of 90 cm for men or 80 cm for women. In this case, BMI alone gives a false negative. Waist circumference, HbA1c, and fasting glucose provide a more complete risk picture.
Sources
- Misra A, et al. "Consensus statement for diagnosis of obesity, abdominal obesity and the metabolic syndrome for Asian Indians and recommendations for physical activity, medical and surgical management." J Assoc Physicians India. 2009;57:163–170.
- Mohan V, et al. (ICMR-INDIAB-17). "Metabolic non-communicable disease health report of India." Lancet Diabetes & Endocrinology. 2023. (101 million diabetics figure; nationally representative sample of 113,043 participants.)
- Caleyachetty R, et al. "Ethnicity-specific BMI cutoffs for obesity based on type 2 diabetes risk in England: a population-based cohort study." Lancet Diabetes & Endocrinology. 2021;9(7):419–426. (10-year T2DM risk at lower BMI in South Asians.)
- WHO Expert Consultation. "Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies." The Lancet. 2004;363(9403):157–163.
- Deurenberg P, et al. "Asians are different from Caucasians and from each other in their body mass index/body fat per cent relationship." Obes Rev. 2002;3(3):141–6. (3–5% higher body fat at same BMI.)