What a calorie floor is, and why we have one
In short
A calorie floor is the lowest daily target Mitta will set: 1,500 kcal for men and 1,200 kcal for women and everyone else. Eating less than that without guidance makes it hard to get enough nutrients, to train well and to recover, and losing weight faster than about 1% of your body weight a week costs more muscle. Mitta also never lowers your target while you are already losing faster than that.
Cody de LeeuwLast checked 29 October 2026 · 4 min read
What the floor does
When Mitta works out a calorie target, by formula at the start or from your own data later, it never goes below:
- 1,500 kcal a day if you chose male in your profile;
- 1,200 kcal a day if you chose female or other.
If the maths comes out lower, you get the floor, and Why? says so. Rest days with a lower carb target do not go below it either.
Why eating too little backfires
When you eat too little for what you do, your body starts to save energy. A consensus statement on this, known as relative energy deficiency, links low energy intake to problems with hormones, bones, mood, recovery and performance, in both men and women.1 For lifters, a very low intake also makes it harder to keep muscle while losing fat. A loss of about 0.5 to 1% of your body weight per week is the pace usually advised to keep as much muscle as possible.2
The other limits
- No faster than 1% a week. If you are already losing more than 1% of your body weight a week, Mitta does not lower your target further.
- Small steps. A new target moves at most 200 kcal at a time.
- Time to see the effect. A new target comes at most once every 14 days.
All the limits are on one page: Our safety limits.
Expert opinion evidence
The exact floors are a practical choice, not a number from one study. The reasons behind them, such as the risks of low energy intake and the advice to lose 0.5 to 1% of body weight a week, are well supported. How we rate evidence
How Mitta does it
Fixed limits, not a judgement call.
Mitta’s limits are fixed numbers in the app, not something an AI decides. When one of them changes your target, Why? tells you.
- Your own target is yoursYou can type your own daily target. The field stops at 1,200 kcal for everyone.
- Not medical adviceIf you have a medical condition, are pregnant or unsure what is right for you, talk to a doctor or dietitian first.
Lose fat without crashing.
Mitta keeps your target above a safe floor and changes it in small steps. Free to start, in the web app for invited testers.
Questions about
What a calorie floor is, and why we have one
Why is the floor different for men and women?
Men usually burn more energy because of a larger body size and more muscle, so the same low intake is a bigger deficit. The floor follows the sex you chose in your profile.
Can I eat less than the floor if I want to?
You can type your own target down to 1,200 kcal. Below that, talk to a doctor or dietitian, who can guide you.
What happens if I lose weight too fast?
If you lose more than 1% of your body weight a week, Mitta will not lower your target further, and Why? tells you why.
Sources
- Mountjoy M, Ackerman KE, Bailey DM, Burke LM, Constantini N, Hackney AC, et al. 2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine, 2023; 57(17): 1073–1097. doi.org/10.1136/bjsports-2023-106994
- Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. Journal of the International Society of Sports Nutrition, 2014; 11: 20. doi.org/10.1186/1550-2783-11-20
Written by Cody de Leeuw. First published 29 October 2026, last checked 29 October 2026. This article is general information, not medical advice. Spotted a mistake? Tell me