Should everyone eat 1,200 calories to lose weight?
Short answerNo
On this page
No. 1,200 calories a day is the low end of the diets the 2013 US obesity guideline suggests for women, a floor, not a target. For a small woman who sits most of the day it’s a modest cut. For a tall, active man it’s about a third of what he burns. Start about 500 under your own maintenance instead.
What we’d do
Ignore the number your friend used. Work out your own maintenance from your size and your steps with the calories calculator, take off about 500, and check it against your floor: your resting burn, and 1,200 a day for women or 1,500 for men, whichever is higher. Eat that for four weeks and let your scale correct it. Most people will find their number is well above 1,200, and that it still works.
If you remember three things
- 1,200 is the guideline’s floor for women. For men it’s 1,500.
- Adults maintain on about 1,600 to 3,000 calories, by the US Dietary Guidelines’ tables, and more if they’re bigger.
- Your target is your maintenance minus about 500. For most people that lands well above 1,200.
Why it sounds right
It’s the number most people have heard. It’s simple, it’s round, and for a small woman who sits most of the day it is a real deficit. And it comes from somewhere real: the 2013 US obesity guideline does suggest diets of 1,200 to 1,500 calories a day for women and 1,500 to 1,800 for men.
What gets lost is the rest of that sentence. The guideline says those levels “are usually adjusted for the individual’s body weight and physical activity levels”, and it offers a second way to set the diet: a cut of 500 or 750 calories a day from what you need. The range was a starting point for a clinic, not one number for every body.
One shoe size
Telling everyone to eat 1,200 calories is like selling everyone the same shoe size. It fits some feet. On others it pinches until you can’t walk, or falls off at the first step. A calorie target only means something against your own maintenance, and adult maintenance runs from about 1,600 to over 3,000.
What 1,200 means for four people
Here’s 1,200 against four bodies, with maintenance from the Mifflin-St Jeor formula and each person’s steps.
| Person | Resting burn | Maintenance | 1,200 is a cut of | At that cut |
|---|---|---|---|---|
| A 30 year old woman, 5 foot 2, 130 pounds, mostly sitting | About 1,260 | About 1,520 | About 320 | About 0.6 pounds a week |
| A 35 year old woman, 5 foot 5, 170 pounds, 6,000 steps | About 1,470 | About 2,020 | About 820 | About 1.6 pounds a week |
| A 40 year old man, 5 foot 10, 200 pounds, 4,000 steps, lifts 3 hours a week | About 1,820 | About 2,290 | About 1,090 | About 2.2 pounds a week |
| A 35 year old man, 6 foot 2, 200 pounds, 12,000 steps | About 1,910 | About 3,300 | About 2,100 | About 4.2 pounds a week |
For all four, 1,200 is under their resting burn. For the two men it’s under the guideline’s floor of 1,500 too. For the tall active man, it’s a crash diet: about 36% of what he burns.
What the US numbers say people need
The 2020 to 2025 US Dietary Guidelines list estimated calorie needs at a healthy weight. For adults aged 19 to 60:
| Sedentary | Moderately active | Active | |
|---|---|---|---|
| Women | 1,600 to 2,000 | 1,800 to 2,200 | 2,200 to 2,400 |
| Men | 2,200 to 2,600 | 2,400 to 2,800 | 2,600 to 3,000 |
Even the least active woman in the table, sedentary and over 50, is listed at 1,600. People who weigh more than the table’s healthy reference weights burn more, not less.
What goes wrong on too few calories
Hunger wins. Appetite rises as you lose, by about 100 calories a day for every kilogram lost in a 2016 analysis. The bigger the cut, the harder that pull.
Muscle goes with the fat. In a 2011 trial of elite athletes, the group that lost 1.4% of body weight a week kept no extra lean mass, while a group losing 0.7% a week gained 2.1%.
Protein gets hard to fit. The 2025 to 2030 US Dietary Guidelines say 1.2 to 1.6 g of protein per kg of body weight a day. At 170 pounds that’s 90 to 125 g, which is 360 to 500 calories of protein alone, up to 40% of a 1,200 calorie day.
And it often isn’t 1,200. In a 1992 study, people who said they couldn’t lose on under 1,200 calories a day were eating nearly twice what they logged. Their burn was normal.
Where it’s partly right
For some people 1,200 is reasonable. A small, older woman who sits most of the day might maintain at about 1,600, and 1,200 to 1,400 would be a steady, ordinary cut for her. The mistake is using it as everyone’s number, or going under it: the same guideline says diets under 800 calories belong only in a medical setting with monitoring.
7 sources
- Jensen et al., 2013 AHA/ACC/TOS guideline for the management of overweight and obesity in adults, Circulation, 2014pmc.ncbi.nlm.nih.gov
- US Department of Agriculture and US Department of Health and Human Services, Dietary Guidelines for Americans, 2020 to 2025, Appendix 2: Estimated calorie needsdietaryguidelines.gov
- Mifflin et al., A new predictive equation for resting energy expenditure in healthy individuals, American Journal of Clinical Nutrition, 1990pubmed.ncbi.nlm.nih.gov
- Lichtman et al., Discrepancy between self-reported and actual caloric intake and exercise in obese subjects, New England Journal of Medicine, 1992pubmed.ncbi.nlm.nih.gov
- Polidori et al., How strongly does appetite counter weight loss? Quantification of the feedback control of human energy intake, Obesity, 2016pubmed.ncbi.nlm.nih.gov
- Garthe et al., Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes, International Journal of Sport Nutrition and Exercise Metabolism, 2011pubmed.ncbi.nlm.nih.gov
- US Department of Agriculture and US Department of Health and Human Services, Dietary Guidelines for Americans, 2025 to 2030realfood.gov
