Do women burn fewer calories than men?

Yes, mostly because women are smaller on average and carry less muscle for their weight. The average American woman burns about 450 fewer calories a day than the average American man when both take under 5,000 steps a day, and about 580 fewer at 7,500 to 9,999. The engine runs the same, though: in a large 2021 study, once lean mass and fat mass were matched, women and men aged 20 to 60 burned the same.

It can feel like women got a slower metabolism. What they mostly got is a smaller body, and calorie needs scale with the size of the body doing the burning. The formulas also take off a fixed amount for women, which stands in for the difference in body makeup.

The simple version

A compact car and an SUV can share the same engine design. The SUV still burns more fuel per mile, because there’s more of it to move.

Where the gap comes from

The average American man is 5 foot 9 and 199 pounds and the average woman 5 foot 3½ and 172 pounds, in CDC measurements for 2021 to 2023. At 40, the Mifflin-St Jeor formula puts them about 375 calories a day apart at rest:

• About 210 from height and weight. He’s taller and heavier.
• About 165 from the sex term. The formula adds 5 for men and takes off 161 for women. Women typically carry more fat than men of a similar weight, and at rest a pound of fat burns about 2 calories a day against about 6 for muscle.

Our calculators multiply resting burn by 1.2 under 5,000 steps a day and 1.55 at 7,500 to 9,999, so the middles of their ranges are 2,160 and 1,710 at the lower band and 2,790 and 2,210 at the higher one: about 450 and 580 apart.

Matched for body makeup

The 2021 study pooled measurements of daily burn from 6,421 people in 29 countries. For adults 20 to 60, sex had no effect on total burn once fat-free mass and fat mass were taken into account.

What to do

• Get your own range from the calories from your steps calculator, which asks your sex for this reason.
• Mind the floor: never under 1,200 calories a day for women or 1,500 for men without a doctor.
• Lift weights. At rest, muscle burns about three times what fat does.