How to measure waist-to-hip ratio
Stand relaxed and measure at the end of a normal breath out. Measure your waist at the midpoint between your lowest rib and the top of your hip bone (for most people the narrowest point of the waist). Measure your hips at the widest part of the buttocks, keeping the tape parallel to the floor.
Ratio = waist / hip. For example, an 80 cm waist and 100 cm hips give a ratio of 0.80. Units do not matter as long as both measurements use the same one: 32 in and 40 in give the same 0.80.
What does your result mean?
The World Health Organization defines a waist-to-hip ratio of 0.90 or more in men and 0.85 or more in women as the point where the risk of metabolic complications rises substantially. This calculator uses these bands:
Men: below 0.90 low, 0.90-0.99 moderate, 1.0 and above high risk Women: below 0.80 low, 0.80-0.84 moderate, 0.85 and above high risk
A high ratio means fat is stored more around the abdomen than on the hips and thighs (the apple shape).
Why belly fat is riskier
Visceral fat, stored around the internal organs, is metabolically active in a way that fat under the skin is not. It is strongly linked to insulin resistance, type 2 diabetes, high blood pressure, unhealthy cholesterol levels and heart disease. In some large studies, waist-to-hip ratio predicted heart attack risk better than BMI.
The good news is that visceral fat usually responds quickly to weight loss and regular exercise. About 150 minutes of moderate activity a week, enough sleep, and cutting back on sugary drinks and alcohol are the most effective ways to bring the ratio down.
Limitations
Waist-to-hip ratio does not measure body fat percentage; it only describes how fat is distributed. Small differences in technique can shift the ratio by 0.02-0.03, so measure at the same points every time. It is less reliable for people with a BMI above 35 and during pregnancy.
The ratio is most meaningful alongside BMI, waist circumference and markers like blood pressure and blood sugar. A waist circumference above 102 cm (40 in) for men or 88 cm (35 in) for women is also a high-risk sign on its own.
When to see a doctor
If your ratio is in the high-risk band, especially with a family history of early heart disease or diabetes, see a doctor to check your blood sugar, cholesterol and blood pressure. If you have symptoms such as chest pain, shortness of breath or excessive thirst, get medical help without waiting.