Calories to lose 1 lb a week
Enter your details and a weekly loss to get a calorie target. The example is a man aged 40 who is 5 ft 10 in tall and weighs 200 lb, aiming to lose 1 lb a week.
How it works
Start with maintenance calories from Mifflin-St Jeor and an activity factor. A pound of body weight is commonly estimated at 3500 calories. Multiply the weekly loss in pounds by 3500 and divide by 7 for the daily deficit. Subtract that from maintenance. For a man aged 40 at 200 lb, this page uses a loss of 1 lb a week.
Worked example
Take a man aged 40 who is 5 ft 10 in tall and weighs 200 lb. Resting calories are 1823.45, and 1823.45 × 1.55 for the moderately active level is 2826.3. That is 2826 calories a day at maintenance. To lose 1 lb a week, multiply 1 × 500 = 500. Then 2826.3 − 500 = 2326.3. The target is 2326 calories a day.
Common questions
Should I recalculate as I lose weight?
Yes. Maintenance falls as weight falls. Check again every few pounds. For this man aged 40, maintenance is 2826 calories a day at 200 lb and about 2756 at 190 lb, with a target of 2326 at 1 lb a week.
How fast is it reasonable to lose weight?
A steady pace of about half a kilogram to one kilogram a week is common. Slower is easier to keep up. Ask your doctor what suits you. For this man aged 40 at 200 lb, 1 lb a week is 0.45 kg a week.
Where does the 3500 calories a pound come from?
It is a rule of thumb for the energy in a pound of body fat. Real results vary because the body adapts as you lose weight. For this man aged 40 at 200 lb, 1 lb a week gives 500 calories a day by the rule.
What if my target is below my resting calories?
Eating below resting calories is hard to sustain and may not be safe without medical advice. Choose a smaller deficit. For this man aged 40 at 200 lb, resting calories are 1823 and the target at 1 lb a week is 2326. The target is 503 calories above resting calories.
Does my activity level change the target?
Yes. Maintenance already includes your activity level. Pick the level that matches a typical week. For this man aged 40 at 200 lb, the sedentary level gives 2188 and the extra active level gives 3465 at maintenance, against a target of 2326 for 1 lb a week.