“How long will it take me to lose 10 kilograms?” is one of the most searched questions on the internet, and almost all the popular answers lie — either through optimism or through advertising. The truth has a concrete, verifiable number, and if you know it from the start, you save yourself months of frustration and dozens of abandoned miracle diets.

In short: in a month you can healthily and sustainably lose between 2 and 4 kilograms of fat. Yes, you’ve seen ads with “minus 8 kg in two weeks.” Let me explain exactly what those kilograms are about and why, for the most part, they’re not what you think.

The simple math behind one kilogram

To lose weight, you need to consume fewer calories than you burn — a calorie deficit. The question is: how much deficit makes one kilogram?

One kilogram of body fat stores approximately 7,700 calories. All the arithmetic flows from there:

• A deficit of 500 calories per day = 3,500 per week ≈ 0.5 kg of fat per week, meaning ~2 kg per month.
• A deficit of 1,000 calories per day = 7,000 per week ≈ 1 kg per week, meaning ~4 kg per month.

That’s it. No diet changes these numbers — they can only change how easy or hard it is to maintain the deficit. A deficit exceeding 1,000 calories per day is hard to sustain and starts costing you muscle mass and energy, which is why 2–4 kg per month is the healthy zone for most people.

So why do some people “lose 5 kg in the first week”?

This is the part that ads exploit and that’s worth understanding once and for all. When you start a diet, especially one low in carbohydrates, you do see the scale drop 3–5 kg in the first few days. The problem: it’s not fat, it’s water.

The body stores carbohydrates as glycogen in muscles and the liver, and every gram of glycogen holds 3–4 grams of water bound to it. When you cut carbs, you deplete these reserves and eliminate the associated water. The scale drops spectacularly, you think it’s working brilliantly — and then in the second week it “stalls.” Nothing actually stalled: the easy water is simply gone and the hard fat has begun, which comes out at the slow, real rate described above.

That’s why crash diets look great in the first few days and disappoint later. And why, if you weigh yourself daily, the first kilo always lies to you.

What this means on your plate, concretely

A 500-calorie daily deficit sounds abstract until you translate it into real foods. Here’s how 500 calories disappear without starving yourself:

• You skip the daily juice/beer and the syrup coffee: ~250–350 kcal.
• You replace the pastry snack with an apple and a yogurt: you save ~200 kcal.
• You switch from frying to baking or grilling for one meal: ~100–150 kcal.

You see that you don’t need to starve. You need to cut the useless calories — exactly the ones that weren’t filling you up anyway. The rest you can figure out precisely with the calorie calculator, which tells you your requirement and how much to cut for a target of 0.5 or 1 kg per week.

The myth that “faster is better”

The most damaging myth about weight loss is that high speed is a sign of success. It’s exactly the opposite. The faster you lose weight through extreme deficits, the more you:

• lose muscle mass along with fat (muscle burns calories, so you’re sabotaging your future);
• risk regaining everything, plus a bonus — the classic yo-yo effect;
• feel constantly hungry and, statistically, give up within a few weeks.

The “boring” 2–4 kg per month has one huge advantage: it stays off. A person who loses 3 kg per month for six months has dropped 18 kg and usually keeps them off. One who loses 8 kg in a month through starvation typically puts them back on, often with interest. Weight loss isn’t a sprint — it’s a long road walked at a steady pace.

There’s also a practical reason not to rush: the scale doesn’t only measure fat. If you’re exercising, especially with weights, you can lose fat and gain a little muscle simultaneously — in which case the number on the scale drops more slowly than expected, even though you clearly look better in the mirror. That’s why it’s worth measuring yourself with a tape measure (waist, hips, thighs) every two weeks and taking a monthly photo. Often, when the scale “stalls,” the centimetres tell you you’re actually making progress. Relying on a single measuring tool can discourage you for no reason.

Frequently asked questions

What is the maximum amount I can lose healthily in a month?

For most people, 2–4 kg of fat. People starting at a much higher weight may lose somewhat more initially (including more water), but as they approach a normal weight, the rate slows naturally.

Why did I lose 4 kg in the first week and then almost nothing?

Because the first few kilograms were largely water tied to glycogen reserves. Once those were depleted, fat remained, which comes out much more slowly. It’s normal and doesn’t mean something isn’t working.

Does exercise help me lose weight faster?

Indirectly, yes — it increases the deficit and protects muscle mass. But you can’t “compensate” through exercise for an uncontrolled diet; it’s much easier to eat 500 calories than to burn them. The best results come from combining both, not from running to earn desserts.

Is it bad if I want to lose weight faster for an event?

For a few days, controlling salt and carbs can make you look more “lean” through water loss — temporarily. But real fat loss can’t be rushed. For an event, be realistic and don’t resort to dangerous diets that leave you without energy exactly when you need it.

If you take one thing from this article, let it be this: judge your progress in months, not days. The scale fluctuates daily due to water, salt, and hormones, but the trend over four weeks tells the truth. Put the numbers on paper, aim for 2–4 kg, and leave the rest to patience. If you feel like not even that is happening, see why you’re not losing weight even though you eat little.

⚕️ This information is for educational purposes only and does not replace the advice of a doctor or nutritionist. For a plan tailored to you, especially if you have a medical condition, consult a specialist.