Women and men do not need the same calories to lose weight. For most adults, a woman’s weight-loss target is around 1,400 to 1,800 calories a day, and a man’s around 1,800 to 2,300. The gap comes from body size, muscle mass, and the formula itself — this guide works it out with a same-age couple, side by side.
Why Do Men Need More Calories Than Women?
Three reasons, in order of size. First, men are on average larger: more height and more weight means more tissue to maintain, and the Mifflin-St Jeor equation charges 10 calories per kilogram of weight and 6.25 per centimetre of height. Second, men carry more muscle and less body fat at the same weight, and muscle burns more energy at rest than fat. Third, the formula itself builds in a sex difference: the final constant is +5 for men and −161 for women, a gap of 166 calories before any activity multiplier.
Hormones play a supporting role. Testosterone promotes muscle growth, which raises resting burn; estrogen influences where fat is stored. But size and muscle explain most of the gap — a large, muscular woman can need more calories than a small, sedentary man.
Worked Example: A Couple, Both 35, Both Lightly Active
Take a woman and a man of the same age and activity level, and run the same calculation for both. She is 70 kg and 168 cm; he is 85 kg and 180 cm. Both are lightly active, multiplier 1.375.
Her BMR: (10 × 70) + (6.25 × 168) − (5 × 35) − 161 = 700 + 1,050 − 175 − 161 = 1,414 calories a day.
Her maintenance: 1,414 × 1.375 = 1,944 calories a day.
Her weight-loss target (500 deficit): 1,944 − 500 = 1,444 calories a day.
His BMR: (10 × 85) + (6.25 × 180) − (5 × 35) + 5 = 850 + 1,125 − 175 + 5 = 1,805 calories a day.
His maintenance: 1,805 × 1.375 = 2,482 calories a day (2,481.9 before rounding).
His weight-loss target (500 deficit): 2,482 − 500 = 1,982 calories a day.
The gap is 2,482 − 1,944 = 538 calories a day of maintenance, and the same 538 at the weight-loss target. Of that gap, 1,805 − 1,414 = 391 calories come from BMR, and the activity multiplier stretches it to 538. About 166 calories of the BMR gap is the formula’s sex constant alone; the rest is his extra 15 kg and 12 cm. Run your own numbers with a calorie calculator — the gap for your household will be different, and it is worth knowing rather than guessing.
The practical consequence is simple: a shared meal plan does not fit two people. If they eat the same 1,800 calories a day, she is in a deficit of only 144 (1,944 − 1,800) and loses about 0.3 pounds a week, while he is in a deficit of 682 (2,482 − 1,800) and loses about 1.4 pounds a week. Same meals, same effort, very different results — the targets were different all along.
Calorie Targets by Sex: Quick Reference
These are starting points for a 500-calorie deficit, computed with Mifflin-St Jeor at age 35 to 40 and light activity. Your own figure depends on your exact weight, height, and age — run it through a calorie calculator rather than reading it off a table.
| Person | Maintenance | Target (500 deficit) |
|---|---|---|
| Woman, 70 kg, 168 cm, lightly active | 1,944 | 1,444 |
| Woman, 70 kg, 168 cm, moderately active | 2,192 | 1,692 |
| Man, 85 kg, 180 cm, lightly active | 2,482 | 1,982 |
| Man, 85 kg, 180 cm, moderately active | 2,798 | 2,298 |
| Man, 90 kg, 178 cm, lightly active | 2,499 | 1,999 |
The moderately active figures use the 1.55 multiplier: her 1,414 × 1.55 = 2,191.7, rounded to 2,192; his 1,805 × 1.55 = 2,797.75, rounded to 2,798. One extra activity level is worth about 248 calories a day for her and about 316 for him. The man in the last row is worked out in full in our guide to how many calories you should eat to lose weight, and the two-step method behind every number here is in our guide to how to calculate TDEE.
How Does Age Change Calorie Needs?
Age trims the numbers for both sexes, because the formula subtracts 5 calories per year of age from BMR, and muscle loss with age adds to the effect. Run the same couple at 55 instead of 35, keeping weight, height, and activity the same:
Her BMR at 55: (10 × 70) + (6.25 × 168) − (5 × 55) − 161 = 700 + 1,050 − 275 − 161 = 1,314. Maintenance: 1,314 × 1.375 = 1,807. Target: 1,807 − 500 = 1,307 calories a day.
His BMR at 55: (10 × 85) + (6.25 × 180) − (5 × 55) + 5 = 850 + 1,125 − 275 + 5 = 1,705. Maintenance: 1,705 × 1.375 = 2,344. Target: 2,344 − 500 = 1,844 calories a day.
Twenty years cost her 1,944 − 1,807 = 137 calories a day of maintenance, and him 2,482 − 2,344 = 138. The sex gap barely changes — 2,344 − 1,807 = 537, almost the same 538 as at 35 — but both targets fall. This is why a meal plan that worked at 35 stops working at 55. Strength training is the best countermeasure, because it defends the muscle that keeps BMR higher.
The Safe Floors Are Different Too
The commonly used floors for unsupervised dieting are about 1,200 calories a day for women and 1,500 for men. Below those levels it becomes genuinely difficult to get enough protein, vitamins, and minerals. The 300-calorie difference mirrors the same size and muscle gap as the rest of the numbers.
The floors matter most for smaller or older women. Our 35-year-old woman’s target of 1,444 sits comfortably above her 1,200 floor. But at 55, her target of 1,307 is only 107 calories above it. If she were also smaller — say 60 kg — a 500-calorie deficit would push her below the floor. The answer is never to eat below the floor: take a smaller deficit, 200 to 300 calories, and add activity to widen it.
For men the floor rarely binds, because most men maintain above 2,000 calories and a 500-calorie deficit still leaves them well above 1,500. The exception is a small, older, sedentary man — his maintenance may be near 1,800, and the same logic applies: smaller deficit, more movement.
What Women and Men Should Do Differently — and the Same
Protein matters more for women in a deficit, relatively speaking. Both sexes should aim for about 1.6 grams of protein per kilogram of body weight a day while losing weight — for our 70 kg woman, about 112 grams; for our 85 kg man, about 136 grams. Because her calorie budget is smaller, protein takes up a bigger share of it, so lean sources matter: eggs, Greek yogurt, chicken, fish, and legumes. Our worked 1,510-calorie day in the guide to how many calories are in common foods shows how roughly 105 grams of protein fits into a day at her scale.
Strength training matters for both, and the payoff is the same. Two to three weekly sessions protect muscle during weight loss, which protects BMR.
The deficit rules are identical. Both sexes lose best on a deficit of 300 to 500 calories a day, or 10 to 20 percent below maintenance, at a pace of about 0.5 to 1 pound a week. Both hit plateaus for the same reasons — maintenance falls as weight falls, tracking slips, weekends erase weekday deficits — and the fixes are the same. Our guide to what a calorie deficit is covers plateau causes and the step-by-step fix.
Do Men Lose Weight Faster Than Women?
On the same deficit, men usually lose faster at first — not because of willpower, but because the same 500-calorie deficit is a smaller percentage of a larger maintenance, and because men typically lose more water weight early on. Over months, the gap narrows: as the man loses weight his maintenance falls, and the woman’s slower start catches up in percentage terms. The fair comparison is percentage of body weight lost, not pounds — 1 pound a week is about 0.65 percent of body weight for our 70 kg woman and about 0.53 percent for our 85 kg man.
If you want the other half of the health picture, your body mass index uses the same weight and height: our woman’s BMI is 70 ÷ (1.68 × 1.68) = 70 ÷ 2.8224 = 24.8, in the healthy 18.5–24.9 range, while our man’s is 85 ÷ (1.80 × 1.80) = 85 ÷ 3.24 = 26.2, in the overweight range. Check yours with our free BMI calculator.
FAQ: Calories for Women vs Men
How many calories should a woman eat to lose weight?
Most women land around 1,400 to 1,800 calories a day for a 500-calorie deficit, but the exact number depends on size, age, and activity. A 35-year-old woman, 70 kg, 168 cm, lightly active, maintains on 1,944 and targets 1,444. Do not go below 1,200 calories a day without medical supervision.
How many calories should a man eat to lose weight?
Most men land around 1,800 to 2,300 calories a day for a 500-calorie deficit. A 35-year-old man, 85 kg, 180 cm, lightly active, maintains on 2,482 and targets 1,982. Do not go below 1,500 calories a day without medical supervision. To get your exact number, find your calories to lose weight with your own age, weight, height, and activity level.
Why do men need more calories than women?
Men are on average taller and heavier, carry more muscle and less body fat, and the Mifflin-St Jeor equation builds in a 166-calorie sex difference (+5 for men, −161 for women). Size explains most of the gap; a large muscular woman can need more calories than a small sedentary man.
Can a woman eat the same calories as a man and lose weight?
She can, but the result differs. If a couple both eat 1,800 calories a day, she may be in a deficit of only about 144 while he is in one of about 682 — she loses about 0.3 pounds a week, he about 1.4. Shared meals need different portions, not different menus.
How many calories should a woman over 50 eat to lose weight?
Less than at 35, because BMR falls about 5 calories a year. Our example woman at 55, same weight and activity, maintains on 1,807 and targets 1,307 — only just above the 1,200 floor. A smaller deficit plus daily walking and strength training is usually the better route than a 500-calorie cut.
Do women lose weight slower than men?
At first, usually yes, because the same 500-calorie deficit is a larger share of a woman’s smaller maintenance, and men lose more water weight early. Over six to twelve months the gap narrows considerably. Compare percentage of body weight lost, not pounds.