Question 1

What is a calorie deficit?

Accepted Answer

A calorie deficit means eating fewer calories than your body burns (your TDEE). Your body makes up the difference from stored energy, mostly fat, which is what causes weight loss.

Question 2

How big should my calorie deficit be?

Accepted Answer

For most people, 300–500 calories per day is a sustainable deficit that leads to about 0.5–1 lb (0.25–0.5 kg) of weight loss per week. Larger deficits work faster but increase muscle loss, hunger and the chance of quitting.

Question 3

How many calories are in a pound of fat?

Accepted Answer

Roughly 3,500 calories per pound (7,700 per kg). So a 500-calorie daily deficit adds up to about one pound per week.

Question 4

Why am I not losing weight in a calorie deficit?

Accepted Answer

Common reasons are underestimating food intake, water retention masking fat loss, or your TDEE being lower than estimated. Track consistently for 2–3 weeks; if the trend doesn't move, reduce intake by another 100–200 calories.

Question 5

What is the lowest safe calorie intake?

Accepted Answer

General guidelines suggest not going below 1,200 calories per day for women or 1,500 for men without medical supervision, as it becomes hard to get enough nutrients.

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