This article has been Fact-Checked by Kendall Kennedy MS, RD, RYT
To lose weight you want to burn more calories than you take in. If you’re aiming for weight loss, how many calories per day should you eat?
By knowing how many calories you can have a day it becomes a lot clearer what you have to do to lose weight. Finding out exactly how much you can eat while still staying in a calorie deficit is a complicated calculation depending on things like age, activity levels, height,…
Luckily there is a simple way to get a good estimation of the amount of calories you can eat a day.
Calculating your calories per day for weight loss
It’s important to keep in mind that every calculation or calculator is ultimately just an estimation. There are all kinds of factors that influence your calorie need. A lot of these factors are ignored to avoid getting too complicated.
Just know that things like age, activity levels, body composition,.. matter.
If the amount of fat on your body is not going down with the estimation it’s time to either increase energy burned or reduce energy absorbed from food.
The first step is to figure out how many calories you need per day to maintain weight. Once you have that number you can decide just how big you want your calorie deficit to be.
Calories per day to maintain weight
A way to get a rough estimate of how many calories per day you need to maintain weight is to fill in the most important variables into a formula. One of the more commonly used formulas is the “Mifflin – St Jeor Formula”.
Here is how you can calculate how many calories you need per day to maintain weight:
Imperial: (4.536 × weight in pounds) + (15.88 × height in inches) − (5 × age) + 5
Metric: 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5
Imperial: (4.536 × weight in pounds) + (15.88 × height in inches) − (5 × age) − 161
Metric: 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161
Again, keep in mind that this is an estimate. The only way to know for sure is implementing this goal and seeing what the results are like.
In theory you could also get lab tests done but that’s an expensive idea.
How big of a calorie deficit for weight loss
Now you know how many calorie you need per day to maintain weight, the next question becomes how big of a calorie deficit do you need for weight loss.
Too much of a calorie deficit for too long can slow down your metabolism, the amount of calories you burn each day.
Not enough of a calorie deficit means slow weight loss and less wiggle room for off days.
In general a calorie deficit of about 300-500 a day comes down to a healthy weight loss rate.
So let’s say your maintenance number was 3000 calories. Then you can aim to consume 2500 calories a day.
Since one pound is about 3500 calories (one kilogram about 8000 calories) you would lose about a pound of body fat per week.
When you first start out you might notice that you’re losing more than that. It’s not necessarily bad, in the beginning this could also be due to less water retention because of better food choices.
Weight loss is not fat loss.
Methods for getting a calorie deficit
A calorie is a measurement for a certain amount of energy. A calorie deficit means you’re absorbing less energy from you’re food than you’re using.
There are 2 main ways you can achieve a calorie deficit:
- Burning more calories
- Absorbing less calories
Ways to get started
One of the most common methods to increase the amount of energy you use is exercising. By exercising you increase the amount of energy your body uses for a while. Not all workouts have the same effectiveness, some burn more calories than others.
Another common method is changing what you eat. This can mean consuming the same amount of food but in smaller amounts or different foods that help you absorb less calories from your food.
Keep in mind that losing weight isn’t only about these two things. A good general rule is how healthier your body is the leaner you will be.
Another thing you can try is losing weight by fasting. It’s not just the not eating that helps you lose weight. Fasting benefits your body in term of health too.
You don’t have to do every little thing perfect to see results. You can for example lose weight without exercising. It just means you have to pay more attention to other aspects of your health.
Don’t worry if things like weight loss plateaus happen, that’s almost inevitable. The trick is to take a good look at what you’re doing and making some changes where possible.
Every situation is different but the minimum calorie intake for women is considered to be 1200 calories per day and 1500 calories per day for men.
Going below this amount can be negative for your health.
In theory you would have to be in a 1000 calorie deficit a day to lose 2 pounds of body fat a week.
This is not considered to be a healthy weight loss rate. Going this fast can have negative health consequences.