A person can appear lean and still carry dangerous visceral fat
For generations, the scale and the BMI chart have served as society's shorthand for health — blunt instruments that measure mass but not meaning. Now, nutritionists and physicians are pointing to a quieter, more precise signal: the ratio of one's waist to one's height, a number that reveals not how much the body carries, but where it chooses to carry it. For South Asian populations in particular, whose genetic inheritance makes them prone to storing dangerous fat around vital organs even at modest weights, this distinction may be the difference between early intervention and silent harm.
- Millions of people receive a clean bill of health from their BMI while visceral fat quietly accumulates around their organs, driving inflammation and insulin resistance unseen.
- South Asians face a compounded vulnerability — genetic predisposition means abdominal fat builds earlier and at lower weights, making standard screening tools dangerously misleading for this population.
- A waist-to-height ratio at or above 0.5 flags elevated cardiometabolic risk that BMI simply cannot detect, offering a critical early warning for diabetes, hypertension, and heart disease.
- The measurement itself demands almost nothing — a string, a navel, and basic arithmetic — yet it surfaces a risk profile that expensive diagnostics often miss.
- Experts are steering people toward sustainable, unglamorous interventions: fewer processed sugars, daily walking, twice-weekly strength training, and consistent sleep to lower cortisol and shrink central fat.
For years, the bathroom scale and BMI calculator have been medicine's default tools for gauging metabolic risk. But nutritionist Pooja Makhija and Dr. Amit Saraf of Jupiter Hospital in Thane argue these measures share a fundamental blind spot: they cannot see where fat lives in the body.
The distinction is not trivial. Visceral fat — the kind that wraps around organs in the abdomen — is metabolically active in ways that fat stored beneath the skin is not. It fuels inflammation and insulin resistance, quietly raising the risk of diabetes, high blood pressure, and heart disease. A waist-to-height ratio of 0.5 or higher signals this elevated cardiometabolic danger even when BMI reads as perfectly normal.
For Indians, the stakes are higher still. South Asian genetics predispose people to accumulate abdominal fat earlier and at lower body weights than most other populations. Someone can appear lean, see a reassuring number on the scale, and still be carrying dangerous amounts of visceral fat. The calculation is simple: divide waist circumference by height. Dr. Saraf offers an even more intuitive method — cut a string to your height, fold it in half, and check whether it fits around your waist.
The path forward, once an elevated ratio is identified, is less about dramatic intervention than consistent habit. Reducing added sugars and ultra-processed foods, walking 8,000 to 10,000 steps daily, adding protein to meals, training for strength twice a week, and protecting sleep — which, when disrupted, raises cortisol and feeds abdominal fat accumulation — are the practical levers available to most people.
BMI and body weight remain useful data points, but they are supporting characters in a story whose protagonist is central fat distribution. For anyone navigating long-term metabolic health — and especially for those with South Asian ancestry — the waist-to-height ratio is the number that tells the truth.
For years, the bathroom scale and BMI calculator have been the standard tools for assessing whether someone is at risk for metabolic disease. But two medical experts argue that these measures miss something crucial: where the body stores its fat. Nutritionist Pooja Makhija and Dr. Amit Saraf, director of internal medicine at Jupiter Hospital in Thane, say the waist-to-height ratio—a simple calculation that divides waist circumference by height—is a far more reliable predictor of whether someone will develop diabetes, high blood pressure, or heart disease.
The distinction matters because not all fat is created equal. BMI tells you how much mass a person carries relative to their height, but it says nothing about whether that mass is distributed around the midsection or elsewhere. Visceral fat—the kind that accumulates around vital organs in the abdomen—is metabolically active and dangerous. It drives inflammation and insulin resistance in ways that subcutaneous fat, stored under the skin, does not. A waist-to-height ratio of 0.5 or higher signals elevated cardiometabolic risk, even in people whose BMI falls comfortably within the "normal" range. This is the gap that BMI cannot see.
For Indians, this distinction carries particular weight. Genetic factors predispose South Asian populations to accumulate abdominal fat earlier and at lower body weights than many other groups. A person can appear lean, step on a scale and see a reassuring number, and still be carrying dangerous amounts of visceral fat. Large global studies have shown that waist-to-height ratio detects this hidden risk far more effectively than BMI alone. The measurement is straightforward: measure your height, then measure your waist circumference at the level of the navel without pulling in your stomach, and divide one by the other. Dr. Saraf offers a practical shortcut: cut a string to your height, fold it in half, and see if that folded length fits comfortably around your waist. If it does not, you likely have excess central fat.
Once someone knows their ratio is elevated, the path forward does not require drastic intervention. The experts recommend sustainable changes focused on reducing belly fat. Limiting added sugars and ultra-processed foods helps, as does walking 8,000 to 10,000 steps daily to improve insulin sensitivity. Adding more protein to meals increases satiety and supports metabolism. Strength training twice weekly targets central fat directly. Sleep matters too—poor sleep raises cortisol levels, which drives abdominal fat accumulation. These are not exotic interventions. They are the fundamentals of metabolic health, applied with intention.
Weight and BMI need not be abandoned entirely, but they should be understood as supporting numbers rather than the main story. Weight tells you how much you weigh. Waist-to-height ratio tells you whether that weight is stored in places that will eventually harm you. For anyone concerned about long-term metabolic health, especially those with South Asian ancestry, the ratio is the number that actually counts.
Notable Quotes
BMI only shows how heavy a person is for their height. It does not reveal how much fat is stored around vital organs.— Dr. Amit Saraf, director of internal medicine, Jupiter Hospital
For long-term metabolic health, waist-to-height ratio is the number that truly counts.— Medical experts cited in the reporting
The Hearth Conversation Another angle on the story
Why has BMI held on so long if it misses the real risk?
Because it's simple to calculate and it correlates with health outcomes at a population level. But simplicity isn't the same as accuracy. BMI was designed in the 1800s for population statistics, not individual risk assessment. It treats a muscular athlete and someone carrying visceral fat the same way if they weigh the same.
So someone could have a "healthy" BMI and still be at high risk?
Exactly. That's the whole point. You can be lean-looking, weigh 65 kilos, and still have dangerous amounts of fat packed around your liver and pancreas. BMI wouldn't flag that. Waist-to-height ratio would.
Why specifically Indians? Is it just genetics?
It's partly genetic, but also dietary patterns and lifestyle factors that have accumulated over generations. Indians tend to develop metabolic dysfunction at lower weights than Europeans or Africans. So a person who looks fine by global standards might actually be at significant risk.
The string trick seems almost too simple. Does it actually work?
It's a practical approximation. The real measurement is more precise, but the string method gives you a quick sense of whether you should pay attention. If the string doesn't fit, you know it's time to look more carefully.
What if someone's ratio is high? How quickly can they improve it?
That depends on consistency. Walking more, eating less processed food, adding protein and strength training—these aren't quick fixes. But they work. The key is that they're sustainable. You're not cutting calories drastically or eliminating food groups. You're shifting habits in ways you can actually maintain.