Understanding BMI: What It Means and Its Limitations
BMI is a useful screening tool but not a perfect measure of health. Here's what you should know about interpreting your BMI score and what other metrics to consider.
Body Mass Index (BMI) is a simple calculation using your height and weight to estimate whether you're in a healthy weight range. It's widely used by doctors and health organizations worldwide as a quick screening tool — but it has important limitations you should know about.
How BMI Is Calculated
BMI = Weight (kg) ÷ Height² (m²). For example, if you weigh 70 kg and are 1.75 m tall, your BMI is 70 ÷ (1.75 × 1.75) = 22.9, which falls in the normal range.
BMI Categories
The standard BMI categories are: Underweight (below 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), and Obese (30 and above). For Asian populations including Indians, health organizations often use slightly lower thresholds since metabolic risk starts at lower BMI values.
Why BMI Is Not the Full Picture
BMI doesn't distinguish between muscle and fat. A very muscular athlete might have a high BMI but low body fat. Conversely, someone with a "normal" BMI can have high body fat percentage (a condition called "skinny fat"). BMI also doesn't account for where fat is distributed — visceral fat around the abdomen is more dangerous than fat in other areas.
Better Metrics to Use Alongside BMI
Use BMI together with waist circumference (risk increases above 90 cm for men and 80 cm for women in South Asians), body fat percentage from our Body Fat Calculator, and regular blood tests for cholesterol, blood sugar, and blood pressure.
Check Your BMI Now
Use our free BMI Calculator to find your BMI instantly. For a more complete health picture, also try the Body Fat Calculator and TDEE Calculator available on CalciHub.
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