What is a calorie deficit?
Your body burns energy every day for breathing, digestion, moving and exercise. That total is your maintenance calories (TDEE). Eat less than that and your body uses stored energy, mostly fat, to make up the difference. That gap is your calorie deficit.
Find your maintenance number in 30 seconds with the calorie calculator.
How big should the deficit be?
| Goal | Daily deficit | Weekly |
|---|---|---|
| Lose 0.25 kg a week (½ lb) | ≈ 275 kcal (250 for ½ lb) | Gentle, easy to sustain |
| Lose 0.5 kg a week (1 lb) | ≈ 550 kcal (500 for 1 lb) | Most common target |
| Lose 1 kg a week (2 lb) | ≈ 1,100 kcal (1,000 for 2 lb) | Aggressive; usually only for higher body weights |
Example: what a deficit looks like
| Person | Maintenance | −0.5 kg/week target |
|---|---|---|
| Woman, 35, 168 cm, 72 kg, lightly active | ≈ 1,970 kcal | ≈ 1,420 kcal |
| Man, 40, 180 cm, 90 kg, lightly active | ≈ 2,520 kcal | ≈ 1,970 kcal |
How low is too low?
Common guidance is not to go below about 1,200 kcal a day for women or 1,500 kcal for men without medical supervision. Very low intakes make it hard to get enough protein, fibre, vitamins and minerals, and they are hard to stick to. If your target falls below these numbers, choose a slower rate of loss or add activity instead.
Tips that make a deficit easier
- Protein at every meal (eggs, yoghurt, fish, chicken, beans, tofu) keeps you fuller.
- Volume foods: vegetables, fruit, soups and salads add bulk for few calories.
- Watch liquid calories: sugary drinks, fancy coffees and alcohol add up fast — especially over the holidays.
- Walk more: 2,000 extra steps a day burns roughly 80–100 kcal for most people.
- Weigh, don’t guess: a tablespoon of peanut butter is easy to double by accident. The cups to grams converter helps when recipes use cups.
Why weight loss slows down
As you lose weight, your body needs fewer calories, so the same intake creates a smaller deficit. Water shifts can also hide fat loss for a week or two. If the scale hasn’t moved in 3–4 weeks, recalculate your maintenance at your new weight and adjust by 100–200 kcal.
This guide is general information, not medical advice. If you are pregnant, breastfeeding, under 18, have diabetes, an eating disorder or another health condition, talk to a doctor or registered dietitian first.
Questions
How many calories should I eat to lose weight?
Start with your maintenance calories (use the calorie calculator) and subtract about 500–550 a day to lose roughly 0.5 kg or 1 lb per week.
Is a 1,000 calorie deficit safe?
It can be for some people with higher body weights, under guidance. For most, a 300–600 kcal daily deficit is easier to sustain and protects muscle.
How long does it take to see results from a calorie deficit?
Most people see the scale trend down within 2–4 weeks. Day-to-day weight jumps around because of water, salt and food in your gut.
Do I need to count calories to be in a deficit?
No, but tracking for a week or two helps you learn portions. Others succeed by eating mostly whole foods, more protein and vegetables, and fewer sugary drinks.