This article has been Fact-Checked by Kendall Kennedy MS, RD, RYT
It’s no secret that you have to be in a calorie deficit in one way or another to lose weight. But what should your calorie intake be for weight loss?
A calorie is a measuring unit for the amount of energy in food and drinks. When you absorb more calories than you use, your body stores the excess energy on your body as body fat.
This is useful if you encounter periods where you can’t eat energy rich foods.
The problem is that too much body fat has all kinds of negative health consequences like for example increased risk of heart disease.
Calculating your calorie intake for weight loss
Everyone needs a different calorie intake for weight loss. How much depends on a lot of different factors. Things like age, gender, height, weight, activity levels,… influence it a lot.
This makes calculating exactly how many calories you need to eat for weight loss a pretty difficult task. It’s possible but it requires different experiments in lab setting.
Luckily there are also ways you can get an estimation that’s fairly accurate for most people.
How you can calculate an estimate will be discussed. Just don’t forget that the actual amount may vary. If you’re not losing weight you might need to change it up and try different amounts.
First you can calculate the amount of calories you need to eat to maintain your weight. After that you can decide how much your calorie deficit should be according to how fast you want to lose weight.
How many calories do you need to maintain weight?
One way you can calculate how many calories you need to maintain weight if by using a formula that takes into account some of the most relevant factors. A commonly used formula is the Mifflin – St Jeor Formula.
This formula is not completely waterproof but it is a useful way to get an estimation.
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) + 5
Metric: 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161
Imperial: (4.536 × weight in pounds) + (15.88 × height in inches) − (5 × age) − 161
The result is the amount of calories you burn at rest. If you exercise, your calorie intake can be a little bit higher.
But again, this is an estimate. In reality your number of calories might be bigger or smaller.
You will have to return to this formula every once in a while when you’re losing more and more. Finally when you hit your weight loss goal, you can calculate how many calories you need to consume a day to stay at that weight.
Weight loss plateaus explained
This formula also partly explains weight loss plateaus.
When you lose weight your body uses less energy to do everything it does.
This is one of the reasons for hitting weight loss plateaus. That’s when you should take another look at the above formula and change it to your current situation.
How much should your calorie deficit be?
Now you have your maintenance number you can think about what your calorie deficit should be.
You need to keep in mind that if you lower the amount of calories you eat too much for too long your metabolism might start to slow down. It’s important to go for a healthy weight loss rate.
One way to stop your metabolism from slowing down is to have higher calorie days every once in a while. How often depends different factors.
If you only plan on eating less calories, you can aim for about 300-500 calories deficit on your diet days. One pound of fat is about 3500 calories (one kg +-8000). This means that you would lose close to a pound per week.
If you also plan on implementing other habits that help you lose weight, a bigger calorie deficit can be fine too.
Methods for getting a calorie deficit
You can achieve a calorie deficit in different ways. Here are a few ideas to get started.
The first way is exercising. You can reach a calorie deficit by increasing the amount of energy your body is using to fuel your physical movements. Not all exercise is made equal. Some workouts burn more calories than others.
The next way is by changing what you eat. You might consume the same foods but in smaller amounts or different foods that make it so you absorb less calories from your food.
Losing weight isn’t just about how many calories you are consuming and how much you are exercising. How healthy your body is influences the way it processes calories.
You can try losing weight by fasting for example. On top of the weight loss from not eating you get a ton of other health benefits that will influence the number on the scale.
You can lose weight without exercising. You just have to pay more attention to the other habits that influence your weight.
How to count how many calories you eat
Now you know how many calories you should aim for the next question is “how do I measure this accurately?”.
Most packaged foods have nutritional values on them. This means the amount of calories in them is right there.
Unpackaged foods like for example vegetables are a bit more difficult to measure. You’ll have to find an app or website that provides an estimation of the nutritional values for these foods.
Then you would weigh just how much you are eating of everything. There are apps to add all these numbers but you can also use a digital spreadsheet or even a piece of paper.
Does source of calories matter?
Some people claim the source and macronutrient ratio of foods doesn’t matter other do.
The answer is yes they influence things.
For example it takes your body more calories to process the same amount of calories from protein as from carbohydrates. Other foods like cayenne pepper can increase the amount of energy you burn too.
These are just small examples. Getting your calories from healthy sources will be beneficial for both your health and weight loss progress.
How does calorie intake for weight loss work?
Now how do these things work?
Body fat is excess energy stored for later use. The amount of energy something contains is measured in calories.
You need calories to carry out all kinds of functions.
Your body uses the energy from the food you eat first. If the amount of energy absorbed from your food is bigger than the amount you use, it get’s stored as body fat.
When the energy in your food is not enough, you convert body fat into usable energy.
Keep in mind that the amount of calories you burn changes with how much you weigh. This is the cause of a lot of weight loss plateaus.
Don’t panic, it happens to everyone. You just have to up your game a bit and you’ll be back to burning fat in no-time.