How Many Calories Should You Eat to Lose Weight?

A calorie target can give your meals some structure, but it is not a magic number. Your needs depend on your body, daily movement and many other factors. The useful question is not how little you can eat. It is how you can eat enough to feel well while making a manageable change over time.

Weight loss generally happens when you use more energy than you take in over time. Food and drinks supply energy; your body uses it to keep you alive, digest food and move. This balance is real, but neither food tracking nor calorie calculators measure it perfectly. Treat the numbers as helpful estimates, not a daily test you must pass.

BMR and TDEE: two different estimates

Basal metabolic rate, or BMR, estimates the energy your body needs at rest for essential functions such as breathing and circulation. Total daily energy expenditure, or TDEE, includes those needs plus movement and digestion. A weight-loss calorie target is usually based on TDEE, not on subtracting calories from BMR.

The Mifflin–St Jeor equation is one common way to estimate resting energy needs. It uses weight in kilograms, height in centimetres and age in years. Its original sex-based equations are shown below; individual physiology can differ, so a professional can help when these categories do not fit your circumstances.

• Men: 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5.
• Women: 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161.

Allow for your everyday activity

To estimate TDEE, calculators often multiply resting needs by an activity factor. These factors range roughly from 1.2 for a sedentary routine to around 1.9 for a very active one. They are estimates, not precise measurements. A desk job with a few workouts may require less energy than an active job with similar workouts.

Choose the description that matches an ordinary week rather than your busiest day. Avoid counting exercise twice by using a high activity multiplier and then adding every workout calorie again. Wearables can be useful for noticing movement patterns, but their calorie estimates are not exact either.

Start with a moderate deficit

A deficit of roughly 500 kcal per day is a common starting point for some adults, not a requirement for everyone. About 0.5–1 kg (1–2 lb) per week is often discussed as a general weight-loss pace, but a 500-calorie deficit does not guarantee that range or its upper end. Smaller bodies or people near their goal may need a smaller deficit and slower pace.

Eating too little can leave you hungry, tired and less able to train or concentrate. It can also make getting enough nutrients harder, contribute to muscle loss and make the routine difficult to sustain. A plan you can repeat is more useful than an aggressive target that leaves you feeling unwell.

Commonly cited general lower limits without supervision are around 1,200 kcal per day for women and 1,500 for men. These are guidelines, not personalized safe minimums or targets to aim for. Many people need more. Very low-calorie diets should only be used under medical supervision.

Look at trends, then adjust gently

Give your starting estimate around two to four weeks before judging the overall trend, unless you feel unwell or have been advised otherwise. Weight changes day to day with water, salt, stored carbohydrate, digestion and menstrual cycles. One higher reading does not tell you that you gained body fat overnight.

If weighing is comfortable for you, use comparable conditions and look at averages rather than isolated readings. Also notice energy, hunger, meal satisfaction and how your clothes fit. If the trend is not moving as expected, review portions and activity before making a small adjustment. Avoid slashing calories in response to a single day.

This guidance is for adults and is not medical advice. Speak with a healthcare professional before changing your diet if you have a medical condition, are pregnant or breastfeeding, are under 18, or have a history of disordered eating. A calorie-focused approach may not be appropriate for you.