The ratio, and what it is actually measuring
Divide your waist measurement by your hip measurement. Both use the same units, so it does not matter whether you measure in centimeters or inches. The number captures where you store fat: a higher ratio means more around the belly, which carries more metabolic risk than the same fat on the hips.
WHO risk bands by sex
| Risk | Men | Women |
|---|---|---|
| Low | below 0.90 | below 0.80 |
| Moderate | 0.90 – 0.99 | 0.80 – 0.85 |
| High (abdominal obesity) | 1.00 and above | above 0.85 |
Thresholds from the WHO Expert Consultation (2008). They are the same values whether you measured in centimeters or inches, because the ratio cancels the units.
Apple vs pear, and why it matters
A high ratio is the "apple" shape — fat around the abdomen. A low ratio is the "pear" shape — fat on the hips and thighs. The two carry very different risk for the same total weight.
Belly (visceral) fat is metabolically active and raises insulin resistance and triglycerides. Hip and thigh fat is largely inert, which is why the ratio predicts risk better than total body fat alone.
Getting the measurement right
- Measure the waist above the hip bone. Take it at the top of the iliac crest, not the narrowest point — those can differ by an inch or two and change the band.
- Breathe normally. Measure at the end of a normal exhale and do not suck in. Measure on bare skin; even thin clothing adds half an inch.
- Before eating, not after. A meal can add an inch or more to the waist. Measure in the morning on an empty stomach and average two or three readings.
- Mind the sex threshold. The same ratio sits in different risk bands for men and women, so read your result against the right column.
Common questions
What is a healthy waist-to-hip ratio?
For women, below 0.80 is low risk; for men, below 0.90. The WHO treats a ratio above 0.85 for women or 0.90 for men as abdominal obesity. The lower the ratio, the lower the associated risk of heart disease and type 2 diabetes.
How do I measure waist-to-hip ratio at home?
Use a non-stretch tape. Measure the waist just above the hip bone at the end of a normal breath out, and the hips at the widest part of the buttocks. Divide waist by hip. A 30-inch waist over a 39-inch hip is 0.77.
Is waist-to-hip ratio better than BMI?
For heart risk, it usually is. BMI cannot tell muscle from fat or belly fat from hip fat, and the INTERHEART study found waist-to-hip ratio predicted heart attack risk more strongly than BMI across every ethnic group studied.
Why is the threshold different for men and women?
Women naturally carry more fat on the hips and thighs, which lowers the ratio, so the cut-offs are set lower. A ratio of 0.88 is low risk for a man but high risk for a woman.
