Weight loss

How fat loss actually works

Updated 29 August 2026

No detoxes, no banned foods, no "lose 10 kg in a month" nonsense — just the mechanism, the numbers for your body, and the handful of habits that decide whether the weight stays off.

One mechanism: the calorie deficit

Every diet that has ever worked — keto, fasting, low-fat, anything — worked by the same route: you ate fewer calories than you burned. The packaging differs; the mechanism does not. That is good news, because it means you can build the deficit out of food you actually like eating.

A sensible deficit is 15–20% below your daily burn (TDEE) — large enough to see progress, small enough to keep your training and your mood intact. Worked example for a 25-year-old, 70 kg, 170 cm man who trains three times a week:

BMR (Mifflin-St Jeor) ≈ 1643 kcal
TDEE (× 1.40 lightly active) ≈ 2300 kcal
Fat-loss target (−20%) ≈ 1840 kcal/day — a deficit of about 460 kcal

Work out your own numbers with the calorie calculator — it uses exactly this method, and never prescribes below your BMR.

How fast is healthy

0.4–0.8% of your body weight per week. At 70 kg that is roughly 0.3–0.6 kg a week — a pace you can hold for months without your training collapsing or hunger running your life.

Crash diets lose weight faster on the scale, but a large share of it is muscle and water. Muscle is the engine that burns calories and the thing that makes a leaner body actually look trained — losing it makes regain almost automatic. Weigh in 2–3 times a week under the same conditions and judge the weekly average, never a single morning.

Protein and lifting: the muscle insurance

In a deficit your body will burn something — protein and strength training decide whether that something is fat or muscle. Two rules:

  • Protein at the high end while cutting: about 2.0–2.2 g per kg of body weight per day — the diet plan page shows what that looks like as actual meals
  • Keep lifting heavy: do not switch to light weights and high reps "for toning" — lifting the same loads you built strength with is the signal that tells your body the muscle is still needed. The beginner plan or dumbbell plan both work fine in a deficit.

Everyday swaps, with real numbers

Computed from the same food data the app uses. None of these ban anything — they buy you calories while keeping the meal recognisable.

Instead of Try Calories saved Protein change
Paneer (full fat) (100g) Low-fat paneer (100g) ~95 kcal +4 g
Chicken curry (150g) Chicken breast (cooked) (100g) ~115 kcal +5 g
Mutton curry (100g) Fish (rohu / surmai) (100g) ~145 kcal -3 g
Cooked rice (cup) Brown rice (cup) ~10 kcal +0.5 g

The quiet one: cooking fat

Ghee and oil carry about 45–50 kcal per teaspoon, and a free-pouring hand easily adds three or four unmeasured teaspoons to a single dish. Measuring cooking fat with an actual spoon is often worth 150–200 kcal a day — as much as a swap, with zero change to what you eat.

When the scale stops moving

First: wait two weeks

Water retention routinely hides fat loss for a week or two — hard training, salty food and poor sleep all hold water. If the two-week average has genuinely not moved, then change something.

Check portion creep

The most common real cause. Portions drift back toward old sizes within a few weeks — especially rice, oil and snacks eaten standing up. Measure again for three days before assuming your metabolism is the problem.

Then adjust one lever

Either eat 100–200 kcal less, or add movement — 2,000 extra steps a day is roughly the same size of lever. Change one thing, hold it two weeks, judge the average again.

Know when to stop cutting

After 10–16 weeks of dieting, a few weeks eating at maintenance restores training quality and sanity, and makes the next phase work better. Fat loss is not meant to be a permanent state — see cutting vs bulking.

Common questions

How fast should I lose weight?

A sustainable rate is roughly 0.4 to 0.8 percent of your body weight per week — for a 70 kg person, about 0.3 to 0.6 kg. Faster than that usually means losing muscle along with fat, constant hunger, and a rebound when the diet ends.

Do I have to give up rice and roti to lose fat?

No. Fat loss is decided by your total calorie intake across the week, not by any single food. Rice and roti are ordinary carbohydrate sources — portion size is what matters. Diets fail when they ban foods people actually eat every day.

Is cardio required for fat loss?

No — the calorie deficit does the losing, and that can come entirely from food. Cardio and daily steps make the deficit easier to hold without eating very little, and strength training is what tells your body to keep its muscle while the fat goes.

Why has my weight stopped dropping?

Usually one of three things: water retention masking fat loss for a week or two (especially after hard training or high-salt days), portions quietly growing back to old sizes, or your body genuinely burning less because it is now smaller. Hold the plan for two weeks before changing anything; then reduce intake by 100 to 200 kcal or add daily steps.

Are fat-burner supplements worth buying?

No. None of them meaningfully change fat loss, some are unsafe, and the money is better spent on protein-rich food. There is no product in this category we would recommend.

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