How Many Calories Do You Actually Need to Lose Weight?

You have probably been told to eat 1,200 calories a day. Or 1,500. Someone at the gym said 1,800. A calculator online said 2,300 and you assumed it was broken.

None of those numbers mean anything without knowing where they came from. And the gap between them is the difference between losing fat steadily for six months and quitting in three weeks, exhausted and convinced your metabolism is the problem.

Here is how to work out the number that actually applies to you.

Why This Happens

Your body burns calories through four separate channels, and most advice ignores three of them.

Your BMR — basal metabolic rate — is what you burn simply existing: keeping your heart beating, your brain running, your body at temperature. For most adults this is 60–70% of total daily expenditure, and it scales with how much you weigh and how much muscle you carry.

NEAT covers everything you do that is not deliberate exercise: walking to the car, standing, fidgeting, housework. This varies enormously between people — as much as 400 calories a day between two individuals of the same weight — and it is why two people on the same diet get different results.

Exercise is what most people overestimate. An hour of hard training is typically 300–500 calories, not the 800 the treadmill claims.

Digestion burns roughly 10% of what you eat, more if your diet is high in protein.

Add these together and you get your TDEE — total daily energy expenditure. That is the number that matters, and a generic "1,200 calories" figure is not connected to it in any way.

What Most People Get Wrong

The most common mistake is cutting too hard, too early.

The logic seems sound: a bigger deficit means faster loss. And for two or three weeks it works. What follows is predictable — hunger becomes constant, training quality drops, sleep gets worse, and NEAT falls quietly as your body moves less to conserve energy. Then you eat normally for one weekend and regain three kilos, most of it water, and conclude the whole thing failed.

A 1,200-calorie target is below the BMR of most adult men and many adult women. You are not slow-metabolism — you were given a number that was never going to work.

The second mistake is treating the number as permanent. Your TDEE falls as you lose weight, because a lighter body costs less to run. The target that produced steady loss at 95 kg will stall you at 85 kg. This is normal arithmetic, not a broken metabolism, and it needs recalculating every 4–6 weeks.

The third is trusting the calorie readout on gym equipment. Those figures ignore your body composition and routinely overstate burn by 20–40%. Eating back "exercise calories" from a treadmill display is one of the quietest ways to erase a deficit.

Your maintenance calories are not a fixed property of your body. They fall as you get lighter, which is why a plan that never changes eventually stops working.

The Fix

Step 1: Estimate your maintenance

The quick version, accurate enough to start:

Bodyweight in kg × 30 = maintenance calories

For a more precise figure, calculate BMR with the Mifflin-St Jeor equation and apply an activity multiplier:

Men: (10 × kg) + (6.25 × cm) − (5 × age) + 5 Women: (10 × kg) + (6.25 × cm) − (5 × age) − 161

Then multiply:

Your week looks like	Multiplier
Desk job, little walking	1.2
Light activity, 1–3 sessions	1.375
Moderate, 3–5 sessions	1.55
Heavy, 6–7 sessions	1.725

A 30-year-old man, 85 kg, 175 cm, training four days a week: BMR = (10 × 85) + (6.25 × 175) − (5 × 30) + 5 = 1,799 TDEE = 1,799 × 1.55 = 2,788 calories

Step 2: Subtract, but not too much

Take 400–500 calories off maintenance. For the example above, that is roughly 2,300 calories a day.

This produces about 0.4–0.5 kg of fat loss per week. It sounds unambitious. It is also the rate people are still following six months later, which is the only rate that matters.

Never drop below your BMR. Below that you are borrowing against recovery, training quality, and muscle.

Step 3: Judge it on weekly averages

Weight fluctuates 1–2 kg day to day from water, salt, and food still in your system. A single high reading is not fat gain.

Weigh yourself daily, but compare this week's average to last week's. If the average is down, it is working — regardless of what any individual morning said.

Step 4: Recalculate every 4–6 weeks

When loss stalls for more than two weeks at a genuinely consistent intake, recalculate at your new bodyweight and take the new deficit from there. Do not simply cut another 500 calories on top. If you are already stalled, work through the five things to check before cutting further first — the cause is usually one of them.

Once you have the number, the harder question is what to eat to hit it. For local food, portioning, and the things that quietly add calories in a Pakistani kitchen, see why most diet plans fail here.

Doing This Without a Spreadsheet

The arithmetic above is not difficult, but doing it by hand every six weeks is exactly the kind of friction that ends a plan. Most people run the numbers once, never revisit them, and stall.

This is what the FitLife app was built for — BMR, TDEE, calorie targets, and body-fat estimates are built in, so recalculating at your new weight takes seconds rather than being a task you keep postponing. It also tracks weight, water, steps, and sleep on one screen, so you can see the weekly trend rather than reacting to a single morning's reading.

Work out your number today, then hold it for two full weeks before changing anything. Two weeks of consistent data tells you more than two months of adjusting every few days.