how many calories do you need?

How Many Calories Do You Need?

Calories are the most important aspect of your diet. The amount of calories you take during the day will define your health status. How many calories do you need?

This and more questions about calories, in this post!

What are Calories?

Calories are a measure of how much energy a food or drink contains. One calorie is defined as the amount of energy needed to raise the temperature of 1 gram (g) of water through 1° Celsius.

The term calorie defines the energy value of foods. Depending on the composition of such foods, the amount of calories will differ.

Calories give you an overview of the energy you take in and spend throughout the day.


The Calorie Balance Model

Based on the 1st Law of Thermodynamics…

“Matter is not created nor destroyed, but transferred”

Applying this law to your body, we obtain the calorie balance model:

The Calorie Balance

Calories In = Calories Out

With this simple model, you can balance the amount of calories you consume with the amount of calories you burn through physical activity.


To lose weight, you need to use more energy than you consume by following a healthy diet.

To maintain weight, the amount of energy used and taken should balance out.

To gain weight, you need to eat more calories than your body uses.

Recommended Calorie Intake

Now that you know what a calorie is, it’s time to get into how many calories you need a day!

Official health organizations in US and Europe recommend to take 2500 kcal/day for men, and 2000 kcal/day for women (source).

However, the amount of calories you need will depend on your age, gender, physical activity, lifestyle, and genetics, among others…


As you may imagine, it is difficult to know accurately the amount of calories you need.

To solve this problem, there are formulas you can use to calculate the caloric intake based on your physical characteristics.

These formulas will give you an estimation of your basal metabolic rate

The Basal Metabolic Rate

The basal metabolic rate (BMR) is the number of calories your body needs to undergo its most fundamental life-sustaining functions.

Calculating the BMR gives you an accurate overview of how many calories your body needs to function properly and develop over time.

The Mifflin-St Jeor Equation accurately calculates your BMR by using your body weight, height size, and age.

The Activity Factor

The activity factor is a number used to define the amount of physical activity you perform on your life. This number is multiplied by the BMR to account for your lifestyle and physical activity.

The BMR and activity factor together will give you an estimation of how many calories you need to take!

To calculate the amount of calories you need, use the calculator on the link below

Obtain Your Calorie Calculator!

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How Many Calories to Lose Weight

To lose weight efficiently, you need to take less calories than the calories your body uses during the day. This is called calorie deficit

The best weight loss rate is about 1lb/week (0.5kg/week). This rate allows you to lose weight in a healthy manner, without putting your muscle nor body functions at risk.

Since 7000kcal/week of calorie deficit corresponds to 1kg of body mass, a daily calorie deficit of 500kcal/day will let you achieve a weight loss rate of 0.5 kg/week.

sounds easy meme

How Many Calories to Gain Muscle

Your body needs of a lot of energy to gain muscle. Building muscle takes time and effort.

To build muscle fast and efficiently, you need to eat more calories than your body uses every day. This will create a calorie surplus that will allow your body to build muscle over time

yes meme

Similarly to what happens when you try to lose weight, the best weight gain rate is of 1lb/week. To achieve such rate, the most recommended calorie surplus is of 500kcal/day above your maintenance calories.

How Many Calories to Stay Healthy

Often health and fitness don’t go along, and you need to differentiate between them. Health is determined partially by your body weight with respect to your height sizes. This is called Body Mass Index (BMI).


Depending on your current BMI, you will need to follow either a calorie deficit, calorie surplus, or simply maintain your weight.

Alternating between calorie surplus and calorie deficit can also provide some benefits by adding a dynamic factor in your body’s metabolism.


Calories are a measure of how much energy a food or drink contains. Generally, men need 2500 kcal/day and women around 2000 kcal/day. The exact amount of calories you need will depend on your age, gender, lifestyle, genetics, and other health conditions.

In this post we’ve seen how to estimate the amount of calories that you need and how to shift this amount to obtain the amount of calories that you need to achieve such goal.

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