Most calorie targets fail in the same way. Someone types their details into a calculator, gets a fierce number, eats like a different person for four days, and then spends the weekend making up for it. By the next Monday the app is deleted and the conclusion is that “tracking doesn’t work”. The tracking was fine. The target was a wish, not a plan.
A target you can keep is one that still looks reasonable on a Thursday, when lunch was late and you are training after work. That usually means starting from what you already eat, then moving a little, rather than jumping to the lowest number you have ever seen on the internet.
Find maintenance before you cut
Maintenance is the amount of food that keeps your weight roughly steady. Formulae can guess it. The scale, over a couple of weeks, is a better witness.
For fourteen days, log what you actually eat. Not the virtuous version you meant to eat. Include the biscuit with coffee, the oil in the pan, the drink after training. Weigh yourself three mornings a week, after the loo and before breakfast, and average those readings so one salty meal does not panic you.
If the average weight barely moves and the logging was honest, the average intake across those two weeks is close to your maintenance. If weight rose, you are a bit above it. If it fell, you are already in a deficit and you may not need a more aggressive target at all.
A formula is still useful on day one, before you have any data. A common research estimate, the Mifflin–St Jeor equation, starts from weight, height, and age, then multiplies by a factor for how active you are. Treat that number as a parking space, not a verdict. Two weeks of real meals will correct it. People overestimate how active “lightly active” is, and the formula cannot see a job that involves a lot of walking or a week of sitting on trains.
Take a smaller cut than your impatience wants
Once you know roughly where maintenance sits, a daily deficit of about 300 to 500 kilocalories is the range most adults can repeat. On paper, a deficit near 500 kilocalories a day lines up with around half a kilogram a week, because a kilogram of body fat stores in the region of 7,700 kilocalories. Real bodies do not pay out that neatly. Water, glycogen, and a missed log all move the scale by more than the fat did.
Smaller people, and many women, often do better at the 300 end. A target that leaves you cold, short-tempered, and unable to finish your gym sets is not “discipline”. It is a deficit that will be repaid later, usually quickly. Faster loss also makes it harder to keep muscle, which is the tissue that makes daily life and future training easier.
Do not set the target by subtracting an extra chunk “to be safe”, and do not eat back every calorie a watch claims you burned. Those estimates are often high. If you want to account for a long run or a heavy session, add a planned snack you can name, rather than a vague licence to graze.
Put protein in the target, not as an afterthought
Calories decide the direction of your weight. Protein decides whether the weight you keep is useful. If you lift, a practical range is about 1.6 to 2.2 grams of protein per kilogram of body weight per day. A 75 kilogram person aiming at the middle of that range is looking at roughly 140 to 150 grams. That is a palm-sized portion at each meal, plus something at breakfast that is not only toast.
High-protein meals are also more filling, which is the real reason the target survives the afternoon. The rest of the calories can come from carbohydrates and fats in whatever mix you can cook and enjoy. There is a fuller walk-through in the macros guide.
Write the weekend into the plan
A weekly average is what your body responds to. Five days at 1,800 and two days at 3,200 is not “1,800 with a couple of slip-ups”. It is closer to 2,200 across the week, and that may be your true maintenance. You have two honest options. Keep the weekdays where they are and accept a slower rate of loss, or bring the weekend down until the average is actually a deficit.
The option that fails is pretending Saturday will look like Wednesday. Plan a higher day. Have the meal out. Log it. Then let Monday be a normal day rather than a punishment.
Change the number on a schedule, not on a mood
Give a new target two full weeks before you judge it. Weigh often enough to see a trend, and look at the weekly average, not the morning after a late dinner. If the average has not moved and the diary is complete, reduce the target by about 150 to 200 kilocalories and run another fortnight. If training has fallen apart, sleep is worse, or hunger is occupying the whole evening, add food back. A target you abandon is worth nothing.
Every four to six weeks, as body weight changes, maintenance changes with it. The number that worked in January will be slightly high by March if you have lost a meaningful amount of weight. Recalculate from a fresh fortnight rather than stacking cuts on top of old cuts until the day is made of black coffee and irritation.
Who should not use this method alone
This is a general approach for healthy adults. It is the wrong DIY project if you are under 18, pregnant, breastfeeding, managing diabetes with medication, or if you have a history of disordered eating. Tracking can make food feel dangerous for some people. If that is you, close the app and speak to a GP or a registered dietitian. A lower number is not a braver number.
In the app. SimplyAI sets a daily calorie and macro target from a short onboarding, then keeps the day on one screen. The target is only useful if you chose a number you can live with — the app will not rescue a target that was too low on day one.