How many calories should I eat? Women need 1,600–2,400 a day and men 2,000–3,000. Chart by age and activity, the Mifflin formula and weight-loss targets.
How many calories you should eat depends on your age, sex, size and how active you are. The Dietary Guidelines for Americans estimate 1,600 to 2,400 calories a day for adult women and 2,000 to 3,000 for adult men, and the NHS uses averages of 2,000 and 2,500. To lose weight, most dietitians advise cutting no more than about 500 calories a day.
Written and medically reviewed by Op. Dr. Mehmet Mehdi Deniz — bariatric and metabolic surgery · Last updated: 25 October 2026
Quick summary:
The table below shows how many calories adults need per day according to the Dietary Guidelines for Americans 2020–2025.
| Age group | Sex | Calories a day — sedentary | Calories a day — active |
|---|---|---|---|
| Adults 19–60 | Women | 1,600 – 2,000 | 2,200 – 2,400 |
| Adults 19–60 | Men | 2,200 – 2,600 | 2,600 – 3,000 |
| Adults 61+ | Women | 1,600 | 2,000 |
| Adults 61+ | Men | 2,000 | 2,400 – 2,600 |
| Children and teens 7–18 | Girls | 1,200 – 1,800 | 1,800 – 2,400 |
| Children and teens 7–18 | Boys | 1,400 – 2,400 | 1,800 – 3,200 |
Source: U.S. Department of Agriculture and Department of Health and Human Services, Dietary Guidelines for Americans 2020–2025, as tabulated in the Merck Manual. The NHS gives a simpler rule: an average man needs about 2,500 calories a day and an average woman about 2,000.
Calorie needs are highest in the late teens and twenties and fall gradually with age. A sedentary woman over 60 needs about 1,600 calories a day, while the same woman in her twenties and active may need 2,400. Pregnancy and breastfeeding raise needs; Mayo Clinic notes that standard calculators can over- or underestimate in those cases and in athletes.
To calculate how many calories you need, start with your resting energy expenditure (REE): the calories your body burns at rest. The Mifflin–St Jeor equation, derived from 498 healthy adults aged 19–78 and published in the American Journal of Clinical Nutrition in 1990, is a widely used formula for estimating resting needs:
Worked example: a 35-year-old woman who weighs 70 kg and is 165 cm tall has an REE of 10 × 70 + 6.25 × 165 − 5 × 35 − 161 ≈ 1,395 calories. That is the floor; daily movement adds to it. For a sedentary woman of her age, the Dietary Guidelines estimate 1,600–2,000 calories a day.
Maintenance calories are the amount that keeps your weight stable: REE plus everything you burn moving. Mayo Clinic's calculator asks for age, height, weight, sex and one of four activity levels, from inactive to very active, and advises treating the result as a starting point. If your weight holds steady over a few weeks at a given intake, that intake is your real maintenance level.
To lose weight you need a calorie deficit: eating fewer calories than you burn. Cleveland Clinic dietitian Julia Zumpano notes that Most dietitians recommend cutting no more than about 500 calories
from your resting metabolic rate. For steady loss of about 1 to 2 pounds a week, Google's AI Overview summarises general targets as follows:
| Goal | Women — calories a day | Men — calories a day |
|---|---|---|
| Steady weight loss (about 1–2 lb a week) | About 1,200 – 1,500 | About 1,500 – 2,000 |
| Do not go below without medical supervision | 1,200 | 1,500 |
| Daily deficit dietitians generally advise | No more than about 500 calories below your needs | |
Targets: Google's AI Overview for "how many calories should i eat to lose weight", 25 October 2026; deficit guidance: Cleveland Clinic. A target this general can be too low for tall or very active people, so calculate your own number first.
For most adults, 1,200 calories a day is too low to sustain. Cleveland Clinic says some people can eat that amount, lose weight and still meet their nutrient needs, but only when it has been judged appropriate for them. A severe cut can lead to nutritional deficiencies, fatigue and irritability, and can slow metabolism.
To gain weight, eat a few hundred nutrient-dense calories above your maintenance level each day, rather than a large surplus. Pair the extra calories with strength training so more of the gain is muscle. Recheck your weight regularly and adjust in small steps.
Counting calories works for many people, but not everyone with obesity can reach a healthy weight through diet alone. If your weight has not moved after a serious, supervised attempt, a doctor may discuss medical options. Start with where your weight sits on our ideal body weight and BMI chart, then compare:
For short-term tips that stay within safe calorie limits, read how to lose weight fast.
Tell us your height, weight, age and what you have already tried. A bariatric team at one of our contracted healthcare institutions holding a health tourism authorization certificate will review whether diet, a non-surgical treatment or surgery fits your case, and Livist Medical coordinates the consultation, travel and stay.
Request your free weight-loss consultation.
Sources: U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans 2020–2025 (via Merck Manual). NHS — Understanding calories. Mayo Clinic — Calorie calculator. Cleveland Clinic Health Essentials — Is eating 1,200 calories a day healthy? Mifflin MD et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-7 (PMID 2305711).
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