Questions about calorie deficits
A calorie deficit is eating less energy in a day than your body uses. Your body spends energy keeping you alive and moving you around. When you eat less than you spend, it makes up the difference from what it has stored, and your weight comes down. When you eat more, it stores the rest.
First it estimates your maintenance, the energy you use in a day, from your height, your weight, your age, your sex at birth and how much you move. Then it subtracts the deficit for the pace you chose. Around 7 700 kcal is stored in a kilogram of body fat, so 550 kcal a day comes to roughly half a kilogram a week, and 1 100 kcal a day to roughly a kilogram.
No. A deficit you can hold for months beats a deficit you can hold for nine days. Half a kilogram to a kilogram a week suits most people, and losing faster than that usually costs you muscle rather than fat. If the pace you picked takes a quarter or more of your daily energy off the table, this page says so.
Because below about 1 500 kcal a day for men and 1 200 for women, eating that little without medical supervision is a different thing from dieting. If the pace you chose would take you under that line, this page shows you the floor instead, and it does not show a timeline, because you would not be losing weight at the pace you chose. There are people for whom a lower intake is right, and the difference is a conversation with a doctor.
It is an estimate built on population averages, and your real numbers depend on your sleep, your medication, your history and things a calculator cannot see. Treat it as a starting point, watch what actually happens over a few weeks, and adjust from there. If nothing moves despite the work, that is worth a conversation rather than a smaller number.
Being tired in a way sleep does not fix. Being cold. Being hungry all day. Mood that has flattened. Hair, skin and nails changing. Periods changing. Any of those is a reason to eat more and to speak to someone, not a reason to try harder.
It is for adults of 18 and over in Malta. If you are pregnant or breastfeeding, if you have or have had an eating disorder, or if you live with diabetes, kidney disease or liver disease, please talk to a doctor rather than using a number from this page. It is a general guide, not a diagnosis, and it cannot see your medical history, your medication or your bloods.
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What a calorie deficit is
A calorie is a unit of energy. Your body spends energy keeping you alive and moving you around. Eat less than you spend, and your body makes up the difference from what it has stored. That difference is a calorie deficit. Eat more than you spend, and it stores the rest.
Nothing about that is complicated. What is complicated is holding it in place while the rest of your life carries on, which is the part a number on a screen cannot do for you.
How this is worked out
First your maintenance, the energy you use in a day. That comes from your height, your weight, your age, your sex at birth and how much you move. If you know your body fat, the estimate switches to an equation that reads your weight and your body fat only, and gets a little closer. The daily calories calculator shows that figure on its own.
Then the deficit comes off. Around 7 700 kcal is stored in a kilogram of body fat, so 550 kcal a day comes to roughly half a kilogram a week, and 1 100 kcal a day to roughly a kilogram. Those two rates are the choice this page gives you, and the gentler one is right more often.
What a safe deficit looks like
Half a kilogram to a kilogram a week suits most people. Below about 1 500 kcal a day for men and 1 200 for women, eating that little without supervision is a different thing from dieting, and this calculator will not show a figure under those. If the pace you chose would take you there, it shows you the floor instead and says why.
A deficit you can hold for months beats a deficit you can hold for nine days. That is the whole rule.
When a deficit has gone too far
Being tired in a way sleep does not fix. Being cold. Being hungry all day. Mood that has flattened. Hair, skin and nails changing. Periods changing.
Any of those is a reason to eat more and to speak to someone. None of them is a reason to try harder.
What actually moves it
Protein at most meals, so you keep muscle while the weight comes off. The protein calculator gives you a range. Movement you would do anyway, rather than movement you will resent by week three. Sleep, because short sleep makes hunger louder. Water, and a rough daily figure is enough.
And medical support where it is right for you, which is a conversation with a Malta-registered doctor who can look at your sleep, your thyroid, what you already take and the rest of the picture. That is a decision a calculator cannot make.
A number is a start, not a plan
A free assessment takes a few minutes. A Malta-registered doctor reads it, tells you what they think is going on, and tells you honestly if we are not the right fit.
Start Your Free AssessmentMalta only. Adults of 18 and over.
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