How many calories per day, by the evidence

What people ask us next.

Q01

How many calories should I eat a day?

For weight maintenance, most adult women need about 1,600-2,400 kcal/day and most men 2,000-3,000, with the low end for older, sedentary people and the high end for young, active ones (USDA and HHS, 2020-2025). Your personal number is your basal metabolic rate, estimated with the Mifflin-St Jeor equation, multiplied by an activity factor of roughly 1.2 to 1.725. Treat any figure as a starting estimate and confirm it against two weeks of scale data.

Q02

How do I calculate my calorie needs?

Estimate basal metabolic rate with Mifflin-St Jeor: for men, 10 times weight in kg plus 6.25 times height in cm minus 5 times age plus 5; for women the same but minus 161. Then multiply by an activity factor: ~1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active. The result is your total daily energy expenditure, the calories to maintain weight. Subtract about 500 for weight loss or add that much to gain.

Q03

How many calories should I eat to lose weight?

A deficit of about 500 kcal/day below your maintenance number targets roughly 0.45 kg (1 lb) of loss per week, based on the rule that a pound of fat stores about 3,500 kcal. Keep the cut moderate, generally no more than 20-25 percent below maintenance, and avoid eating below your resting metabolic rate for long. As you lose weight your maintenance number falls, so the deficit shrinks and has to be reset every few kilos.

Q04

Why am I not losing weight in a calorie deficit?

The usual reason is that the deficit is smaller than it looks: calorie labels and portion estimates commonly run 20-25 percent low, activity multipliers are overrated, and metabolic adaptation lowers your burn as you lose. Water, salt, and glycogen shifts also mask fat loss for days at a time. The fix is to weigh the two-week trend rather than a single morning, tighten portion accuracy, and cut another 100-200 kcal only if the trend is genuinely flat.

Q05

How many calories do I burn at rest?

Your basal metabolic rate, the energy spent at complete rest, is 60-70 percent of your total daily burn. For a 70 kg, 175 cm, 35-year-old man it is about 1,650 kcal; for a 60 kg, 165 cm woman of the same age about 1,320, using Mifflin-St Jeor. Larger, taller, younger, and more muscular bodies burn more at rest. This resting figure, not your workouts, is the biggest single piece of the calorie total.

Q06

Do I have to count calories to lose weight?

No. Counting works because it makes energy balance visible, but the same deficit can be reached by controlling portions, prioritizing protein and fiber to blunt hunger, and cutting the highest-calorie liquids and fried foods. Many people do best counting for two to four weeks to learn portion sizes, then maintaining the habits without daily logging. What is not optional is the energy gap itself: weight loss still requires eating less than you burn.