The short answer
Your waist should be less than half your height. A 6-foot guy (72 inches) wants a waist under 36 inches. That's a waist-to-height ratio under 0.5.
The math: waist in inches divided by height in inches. A 38-inch waist at 5'10" is 38 divided by 70, or 0.54. Over the line.
The chart
Height | Healthy waist | High risk |
|---|---|---|
5'6" (66 in) | Under 33 in | 40 in and up |
5'8" (68 in) | Under 34 in | 41 in and up |
5'10" (70 in) | Under 35 in | 42 in and up |
6'0" (72 in) | Under 36 in | 43 in and up |
6'2" (74 in) | Under 37 in | 44 in and up |
Between 0.5 and 0.6 is the yellow light. UK health guidelines put that range at increased risk and 0.6 and up at high risk.
Why this beats BMI and the scale
BMI only knows your height and weight. That's like judging a pickup by its total weight without checking whether the bed is full of tools or trash.
Your waist tracks the fat that matters most: visceral fat, the kind packed around your organs. It's tied to heart disease and type 2 diabetes, and research reviews have found waist-to-height ratio predicts that risk better than BMI.
How to measure it right
Morning, before breakfast.
Bare skin. Shirt up.
Find the spot halfway between your lowest rib and the top of your hip bone. For most guys that's about belly-button level.
Tape snug, flat, and level all the way around. Not digging in.
Breathe out normally. No sucking in. The tape doesn't grade on effort.
Measure your height once, barefoot, against a wall.
Same spot, same time, every week. Sunday morning works.
The 3 moves
Move 1: Measure every Sunday. Write it down. Aim for half an inch a month. Slow, and real.
Move 2: Eat 1 gram of protein per pound of goal weight. It protects your muscle while the fat comes off. Here's the math on protein to lose fat after 40.
Move 3: Lift 3 times a week. Sets of 5 to 12 reps that get harder over time. Lifting makes sure the inches you lose are fat, not muscle.
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I'm Jason, a dad of two in my 40s. Every Tuesday and Thursday I send one idea and three moves for dads who want to drop body fat and build muscle at the same time. Five minutes to read. Free.
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Common questions
What's a good waist size for a man?
Under half your height. And for almost any man, a waist over 40 inches is where health risk climbs, even if you're tall.
Is waist-to-height ratio accurate for muscular guys?
More accurate than BMI. Big shoulders and strong legs don't add inches at your belly button. It's not perfect, but it's hard to fool.
How fast can I shrink my waist?
Half an inch a month is a solid pace you can keep. That's 3 inches in 6 months, enough to take a 5'10" guy from 37 inches to 34 and under the line.
Keep reading
I'm not a doctor. If you have a medical condition or take medication that affects your weight, check with yours before changing how you eat or train.