The first question that arises when you want to lose weight is this: how many calories do I need to lose weight? Indeed, it is this caloric intake which is directly responsible for taking or, conversely, for weight loss. In this article, find out:
How many calories you will need to eat per day to lose weight.
How many calories to lose weight? Calculate your energy needs
To find out how many calories you need daily, you will need to estimate your energy needs. Good news, some scientific methods and calculations allow you to fairly accurately estimate your daily energy requirement.
First, it is essential to calculate your basal metabolism. That is to say the minimum amount of energy necessary for your organism at rest to ensure its vital functions: digestion, posture, functioning of the organs, maintenance of the body temperature, etc.
Here is the Harris and Benedict formula used to calculate basal metabolism:
- For men = [13.7516 x Weight (kg)] + [500.33 x Height (m)] – (6.7550 x Age ) + 66.473
- For women: [9.5634 x Weight (in kg)] + [184.96 x Height (in m)] – (4.6756 x Age ) + 655.0955
For example, for a 35 year old woman measuring 1.60 m and weighing 58 kg, we obtain a basic metabolism of:
554.6772 + 295.935 – 163.646 + 655.0955 = 1342
To meet her basic needs, this woman will then need 1,342 kcal per day.
Level of physical activity
To calculate how many calories a day the body needs, it is also necessary to take into account the level of physical activity. In fact, in addition to ensuring its vital needs, the body expends additional calories linked to daily activity. The basic metabolism estimated above should therefore be multiplied by a coefficient corresponding to the level of daily activity.
|Level of physical activity||Coefficient|
|Light physical activity||1.375|
|Moderate physical activity||1.55|
|Intense physical activity||1,725|
|Very intense physical activity||1.9|
Let’s take the example of our 35-year-old woman. If his daily physical activity is moderate, his basic metabolism will have to be multiplied by 1.55 to obtain his daily calorie requirement, or 2080 kcal.
Total energy requirement
Thanks to the previous calculations, we obtained an assessment of the total energy requirement. In our example, it is 2080 kcal. In other words, by consuming 2080 kcal per day, this woman will neither gain nor lose weight. Be careful however, this calculation has some limits. To know your needs as precisely as possible, it is recommended to consult a nutrition professional. Only he will be able to adapt this calculation according to your body and its specific needs.
The importance of the right number of calories per day to lose weight
When it comes to weight loss, it’s all about balance. Calculating the right number of calories per day necessary to lose weight is an essential step.
Here are the 3 possible situations:
- the energy supply is equal to the energy requirement: the weight remains stable
- energy intake is lower than energy need: there is weight loss
- energy intake is greater than energy need: there is weight gain
To lose weight, we consider that it is necessary to induce an energy deficit of the order of 10 to 15% of the total energy need. In our example, it will then be necessary to consume less than 1870 kcal per day for a significant weight loss.
Be careful however, the energy deficit should not be too great at the risk of causing nutritional deficiencies and harmful coping mechanisms. Indeed, below a certain number of calories, the body protects itself by saving its energy and by storing in a more important way the calories ingested. As a result, weight loss becomes more and more difficult and the yo-yo effect inevitable.
Calculating calories to lose weight is not enough
Calculating calories to lose weight is never enough. In practice, the body does not only ingest calories but above all nutrients. A calorie restriction is useless if the diet does not promote the consumption of essential nutrients for the functioning of the body. Indeed, 50 kcal of chocolate cookies and 50 kcal of apple are equivalent in terms of calories but not nutritionally.
The content of food in proteins, lipids, carbohydrates but also in micronutrients is essential to maintain a good balance and promote a healthy and lasting weight loss.
Example of a menu to lose weight permanently
In practice, here is an example of a typical calorie-controlled menu for healthy weight loss. Depending on your specific needs and your level of physical activity, this basic menu will need to be adapted.
|1 green tea |
150 ml vegetable milk
40 g nut muesli
100 g compote without added sugar
|150 g of raw vegetables |
100 g poultry
200 g of green vegetables in olive oil
30 g wholemeal bread
1 fresh fruit
15 g oil seeds
100 g cottage cheese with honey
|200 ml vegetable soup |
100 g white fish
120 g cooked whole starchy foods
30 g cheese
1 fresh fruit