How a calorie deficit works
You lose weight when you consistently eat fewer calories than you burn. The gap is your calorie deficit. A deficit of about 500 calories a day adds up to roughly 3,500 calories a week, which is close to one pound of body fat.
Choosing a pace
Slower is usually better. Losing 0.5–1% of your body weight per week preserves more muscle, is easier to stick to, and is less likely to bounce back. Faster rates (2 lb a week) make more sense when you have more weight to lose.
Making the deficit easier
- Keep protein high (see the protein calculator) to protect muscle and stay full.
- Lift weights 2–4 times a week so the weight you lose is mostly fat.
- Walk more: daily steps are an easy way to widen a deficit without eating less.
- Expect plateaus. Water retention can hide fat loss for a week or two.
Frequently asked questions
What is a safe calorie deficit?
For most adults, 300–750 calories below maintenance, or about 0.5–1% of body weight lost per week. Going below 1,200 (women) or 1,500 (men) calories a day is generally not recommended without medical supervision.
Why did my weight loss stall?
As you lose weight your maintenance calories drop, so the same intake becomes a smaller deficit. Water retention can also mask fat loss. Recalculate with your new weight and give it two weeks before changing anything.
Do I need to count calories to be in a deficit?
No, but tracking for a few weeks teaches you portion sizes and makes the deficit much more reliable.
These results are estimates for healthy adults and are not medical advice. If you are pregnant, breastfeeding, under 18, or managing a medical condition, talk to your doctor or a registered dietitian.