Is 1,200 calories a day too low?

For men, yes: the floor for men is 1,500. For women, 1,200 is the lowest to go without a doctor, and for many it’s lower than they need. The average American woman burns about 1,430 calories a day lying completely still. Eating under your resting burn for months is a crash diet with a nicer name. Start from your own numbers.

1,200 shows up everywhere as the diet number, so it sounds like a target. It’s a floor. The 2013 US obesity guideline lists diets of 1,200 to 1,500 calories a day for women and 1,500 to 1,800 for men, adjusted for body weight and activity. So 1,200 is the bottom of a range, a fit for small and inactive women. The same guideline keeps diets under 800 a day for medical settings only.

The simple version

Picture a ladder. 1,200 is the bottom rung for women. Many women should start a few rungs up, and the rung that’s yours is set by your own resting burn.

Who it’s too low for

Resting burn is from the Mifflin-St Jeor formula, and the average bodies are from CDC measurements for 2021 to 2023. Only the first woman can eat 1,200 without going under her resting burn.

What to do

• Find your resting burn on the BMR calculator and keep your target above it.
• Let the calories to lose calculator set a target that respects both floors.
• If you’re pregnant, breastfeeding, under 18, or have had an eating disorder, set your number with a doctor.