Calorie Deficit to Lose 2 Pounds a Week: The Upper Limit

To lose 2 pounds (0.9 kg) a week, the 3,500 kcal per pound rule asks for a calorie deficit of about 1,000 kcal a day. For 1 kg a week it’s 1,100 kcal, and for 1 lb it’s 500. Two pounds is also the top of the NHS range. It stays within 1% of body weight only at 91 kg (200 lb) or more, and real loss usually comes in lower.

What calorie deficit do I need to lose 2 pounds a week?

About 1,000 kcal a day. The rule that Hall and colleagues describe counts one pound of weight lost as 3,500 kcal. Two pounds is 7,000 kcal, and 7,000 ÷ 7 days is 1,000. In metric the same rule gives about 7,700 kcal per kg, so 1 kg a week costs 1,100 kcal a day. In kilojoules, 1,000 kcal is 4,184 kJ, and 500 kcal is 2,092 kJ. If the idea of a gap itself is new, start with what a calorie deficit is.

The table puts the usual paces side by side, and its last two columns show who can use each one. Two limits produce them: 1% of body weight a week, and the start of the prescribed ranges in the AHA, ACC and TOS guideline: 1,200 kcal for women and 1,500 kcal for men.

Weekly loss	Daily gap	Weekly gap	Lowest body weight at the 1% limit	Lowest maintenance (women / men)
1 lb (0.45 kg)	500 kcal	3,500 kcal	45 kg (100 lb)	1,700 / 2,000 kcal
1.5 lb (0.68 kg)	750 kcal	5,250 kcal	68 kg (150 lb)	1,950 / 2,250 kcal
2 lb (0.91 kg)	1,000 kcal	7,000 kcal	91 kg (200 lb)	2,200 / 2,500 kcal
2.2 lb (1 kg)	1,100 kcal	7,700 kcal	100 kg (220 lb)	2,300 / 2,600 kcal

Take the 2 lb row. You need to weigh at least 91 kg, and your maintenance minus 1,000 must stay at or above your floor. Fail either test and 2 lb a week is off the table.

The 1% limit comes from a review by Helms and colleagues. They wrote it for lifters in contest prep, and it sets intake to lose about 0.5 to 1% of body weight a week. I treat it as a ceiling for everyone, not just lifters.

A pace of 1 lb a week passes the weight limit for anyone at or above 45 kg (100 lb), which is nearly every adult. So 2 lb is a different kind of target from 1 lb.

Can I lose 2 pounds a week at my weight?

Only at 91 kg (200 lb) or more, with a maintenance that clears the floor. This table gives the ceiling at six body weights, at 1,100 kcal per kg of weekly loss.

Body weight	1% a week	Daily gap at that pace	2 lb a week allowed?
55 kg (121 lb)	0.55 kg (1.2 lb)	605 kcal	No
70 kg (154 lb)	0.70 kg (1.5 lb)	770 kcal	No
80 kg (176 lb)	0.80 kg (1.8 lb)	880 kcal	No
91 kg (200 lb)	0.91 kg (2.0 lb)	1,001 kcal	Yes, just
100 kg (220 lb)	1.00 kg (2.2 lb)	1,100 kcal	Yes
120 kg (265 lb)	1.20 kg (2.6 lb)	1,320 kcal	Yes, but the NHS tops out at 1 kg

In the UK, 91 kg is 14 stone 4 lb. The NHS aims for 1 to 2 lb a week. So even at 120 kg the practical ceiling is 1 kg, or 1,100 kcal a day.

Weight is one filter, and maintenance is the other. A woman who weighs 95 kg but maintains at 2,000 kcal can’t take a 1,000 kcal gap. She would eat 1,000 kcal, under her 1,200 kcal floor, so her ceiling is 800 kcal.

Your own ceiling: multiply your weight in kilograms by 11 for a daily gap in kcal. Then subtract your floor from your maintenance. Whichever number is smaller is your biggest gap.

The calorie calculator turns your age, height, weight and activity into a NASEM 2023 estimate. It won’t plan below 1,200 kcal for women or 1,500 kcal for men.

Why is 2 pounds a week the upper limit and not a goal?

It is the top of the published range, and it overstates the result. The NHS says to aim for 1 to 2 lb a week, and the CDC calls about 1 to 2 pounds a week a gradual, steady pace. Neither goes past 2.

The rule overshoots in practice as well. Thomas and colleagues compared the 3,500 kcal rule with seven weight-loss experiments in which intake was supervised or measured. They found it grossly overestimates loss. Take the rule at face value and 2 lb a week for 52 weeks is 104 lb (47 kg), which would leave a 70 kg adult at 23 kg, a result no one reaches because a lighter body uses less energy and the gap closes. The rule also treats every kilogram alike, while Hall’s figures put the energy in a kilogram of lost weight anywhere between about 1,800 and 9,400 kcal, depending on whether it is lean tissue or fat.

Hall’s model shows the same slowing. It has a 100 kg sedentary man cutting 2 MJ (480 kcal) a day and levelling off near 75 kg, with about a year to reach half of that loss and about three years to reach 95%. The first weeks sit closest to the rule.

Muscle pays for it as well. In the review by Helms and colleagues, deeper deficits pull a larger share of the loss from lean mass. My default is 1 lb a week, with 2 lb kept for the heaviest adults. For the gap most adults can hold, see the guide to a calorie deficit to lose weight.

What happens to my 2-pound pace as I lose weight?

The ceiling falls with you, and so does maintenance. In the NASEM equations, each kilogram lost lowers a low active man’s maintenance by 14.94 kcal. Take a man who starts at 100 kg on a 1,000 kcal gap. He is inside the limit. About 9 kg later he weighs 91 kg and 1,000 kcal is too big, while his maintenance has dropped 134 kcal. On the same food his gap is down to about 866 kcal. That is 0.78 kg a week, and he changed nothing.

I recalculate after every 5 kg, and I’d do the same. Move to 1.5 lb a week (750 kcal) when your weight drops under 91 kg, and to 1 lb (500 kcal) under 68 kg. Both steps come from the first table.

What should I aim for if I weigh under 91 kg?

One pound a week, which needs 500 kcal a day. Between 68 and 91 kg you can step up to 1.5 lb, and at 70 kg the ceiling of 770 kcal leaves 750 just inside.

Hold the gap for two weeks, then compare weekly average weights. The rule predicts 0.45 kg a week for 500 kcal, and the real average will usually fall short. A shortfall like that is the rule overpromising and says nothing bad about your gap. A 7-day calorie deficit meal plan shows what 500 kcal under maintenance looks like on a plate, and calorie deficit meal prep cooks a week in two batches.

This target only suits adults who have a reason to lose weight. If you’re pregnant, breastfeeding, under 18, on medication or living with a health condition, your doctor sets the plan. A past eating disorder calls for a professional first. The guideline puts diets under 800 kcal a day in medical settings.

If counting calories has started to feel hard to stop, or eating feels out of control, talk to someone: ANAD in the US (1-888-375-7767), Beat in England (0808 801 0677), NEDIC in Canada (1-866-633-4220) or the Butterfly Foundation in Australia (1800 33 4673). If you’re in danger right now, call your local emergency number. Other UK numbers and crisis lines are on our crisis support page.