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Waist-to-Height Ratio

One tape measure, one division, one number that predicts risk better than BMI. The published categories, and the cutoffs researchers name on tape.

waist circumference ÷ height, both in the same unit. Adults with a BMI under 35, both sexes, all ethnicities, including people with high muscle mass. Not a diagnosis.

The short answer

Keep your waist under half your height. 0.4 to 0.49 is the healthy band. From 0.5 upward the risk of type 2 diabetes, high blood pressure and heart disease rises, and the boundary is the same for men and women.

72 in tall, 36 in waist

36 ÷ 72 = 0.50

165 cm tall, 80 cm waist

80 ÷ 165 = 0.48

Find the bottom of your ribs and the top of your hips; measure midway between them, breathing out naturally.

Waist-to-height ratio chart

The Ashwell Shape Chart bands and the NICE category names, side by side. Find your ratio, read across.

Ratio	Shape Chart	NICE category	Risk	Sources
Below 0.4	Take care	not categorised	underweight range on the Shape Chart	Study0.4 boundary set pragmatically^a
0.4 to 0.49	OK	Healthy central adiposity	no increased health risk	waist under half your height¹
0.5 to 0.59	Consider action	Increased central adiposity	increased risk of type 2 diabetes, hypertension and cardiovascular disease	Study0.5 to 0.6: increased mortality risk^b
0.6 or more	Take action	High central adiposity	further increased risk	Studyyears of life lost rise after 0.6^c

Boundaries: 0.4, 0.5 and 0.6. The 0.5 line held for men and for women across 14 countries in the pooled analysis, which is why there is one chart and not two.

Your waist at each boundary, by height

Height times 0.4, 0.5 and 0.6. Find your height, and the middle column is the waist you want to stay under.

Height	Waist at 0.4	Waist at 0.5	Waist at 0.6
150 cm (59.1 in)	60 cm	75 cm	90 cm
155 cm (61.0 in)	62 cm	78 cm	93 cm
160 cm (63.0 in)	64 cm	80 cm	96 cm
165 cm (65.0 in)	66 cm	83 cm	99 cm
170 cm (66.9 in)	68 cm	85 cm	102 cm
175 cm (68.9 in)	70 cm	88 cm	105 cm
180 cm (70.9 in)	72 cm	90 cm	108 cm
185 cm (72.8 in)	74 cm	93 cm	111 cm
190 cm (74.8 in)	76 cm	95 cm	114 cm
195 cm (76.8 in)	78 cm	98 cm	117 cm
200 cm (78.7 in)	80 cm	100 cm	120 cm

Centimetres, rounded to the nearest whole. Divide by 2.54 for inches.

Cutoffs from the sources

The highlighted column is not from the chart. Each line is what a researcher said on tape, verbatim, at the second linked. The waist-circumference and waist-to-hip cutoffs below are the other numbers researchers gave for the same question.

1
waist under half your height · all

“your BMI is less relevant to me than your eye color but if your waist circumference is more than 50% of your height you should be concerned”
Dr. Peter Attia, on Huberman Lab, at 96:54
2
under 40 in men, 35 in women

“it's highly correlated with visceral fat if it's greater than 40 in in man or 102 cm you're in trouble and if it's over 35 in in women or 88 CM you're in trouble”
Mark Hyman, on The Dr. Hyman Show, at 24:09
3
under 35 in women, 40 in men

“total cholesterol to HDL ratio less than 3.5 to 1 waist circumference less than 35 in for women or 40 in for men and blood pressure less than 120 over 80”
Dr. Casey Means, on Huberman Lab, at 62:58
4
waist-to-hip under 0.7

“for a female if it's less than 0.7 then your chance of having clinically significant aberration in visceral fat are low and then if it's greater than one you likely have higher levels of visceral fat”
Dr. Mary Claire Haver, on Huberman Lab, at 54:03

Sources from published studies

No researcher on file names a number for these rows. Each line below is one sentence copied from a published paper, with the link to it. A cell marked Study points here.

a
0.4 boundary set pragmatically · the 0.4 line was chosen on practical grounds; no measured risk below it

Similar pragmatic reasoning has been used for the boundary value of WHtR 0.4 [25] .
Ashwell et al., PLoS One 2014, full text
b
0.5 to 0.6: increased mortality risk · British non-smokers at ages 30 and 50, both sexes

Both sexes, certainly at the lower two representative ages, have an increased risk of mortality if they are in the ‘Consider Action’ (WHtR 0.5 to 0.6) range.
Ashwell et al., PLoS One 2014, full text
c
years of life lost rise after 0.6 · years of life lost, British non-smokers, both sexes

YLL increases markedly after WHtR 0.6 in both sexes (the ‘Take Action’ category).
Ashwell et al., PLoS One 2014, full text

What this chart does not tell you

It is a screen, not a scan. The ratio tracks visceral fat well at population scale. For one person, a DEXA visceral-fat reading is the direct measure.
Where you measure moves the number. Midway between the ribs and the hips, breathing out, tape level. Measuring at the belt line or after a meal shifts the ratio by a few hundredths, which is a category at the boundary.
Above a BMI of 35 the categories stop applying. The published guidance limits them to adults under that line. Ethnicity-specific cutoffs exist in the research but come from narrower samples, so we did not print them.

That's one number. Where do you stand on the rest?

The free assessment scores you on 11 targets researchers set on the record, from sleep to strength. It takes 14 questions and about 3 minutes, with no labs needed, and shows the one target holding you back most.

Check where I stand

Precis membership

The chart is the easy part. Moving the number is the argument.

Every category, both worked examples and the cutoffs from the sources above are free.

A free account adds

What the evidence says shifts visceral fat first, and in what order to change diet, sleep and training
The blood markers researchers pair with waist size: fasting insulin, triglyceride-to-HDL, ApoB, with their stated targets
Where the sources split on whether a lean person with a high ratio should act

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Where these numbers come from

Categories are the Ashwell Shape Chart and the NICE NG246 categories, as published in Ashwell 2025 (Nutrition Today). Ashwell M. Nutrition Today, 2025. doi:10.1097/NT.0000000000000778; Ashwell M, Hsieh SD. Int J Food Sci Nutr. 2005;56(5):303–307; Browning LM, Hsieh SD, Ashwell M. Nutr Res Rev. 2010;23(2):247–269.
NICE guideline NG246 is cited through Ashwell 2025, written by a committee member, because nice.org.uk could not be read from our network. The category names and boundaries match that reproduction word for word.
Every line in the sources column is verbatim. Tape lines are checked against the transcript at build; study lines were checked against the paper on 6 October 2026. A cutoff nobody stated does not appear.

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