How many calories a day do I have to lose to lose weight?

Are you overweight or just want to lose some of those extra pounds to get a flat stomach?
You can lose weight and notice the first results in just one week. Yes, nothing more and nothing less than seven days.
How?
Well, combining a balanced and healthy diet with regular physical activity and a weight loss program optimized to lose calories.
The equation seems very simple: eat less and better, play sports to burn fat, and incorporate what we call a “caloric deficit.”
Apples are a star food in all diets.
To count the calories you must burn in a day, it is essential that you know (using mathematical formulas) your base metabolism , or basal metabolism . To do this, you can use this formula from Harris and Benedict (1918) revised in 1990 by Mifflin St. Jeor:

Women: BMR = (10 x weight in kg.) + (6.25 x height in cm) – (5 x age in years) – 161
Men: BMR = (10 x weight in kg.) + (6.25 x height in cm) – (5 x age in years) + 5
This way of calculating calories allows us to identify the level of daily caloric consumption that our body needs to cover its physiological needs (heart, pulmonary system, blood circulation, irrigation of the brain and vital organs): it is the necessary expenditure of the human body to continue functioning even in a resting situation.
To this we must add the caloric deficit to which we undergo a weight loss process: we voluntarily consume fewer nutrients so that the number of calories (kcal) we absorb daily is lower than the basal metabolism.
The body will pull its “strock” of stored energy if we do not give it through a diet full of fats and sugars. As a result, we will limit our caloric intake, reduce fluid retention and lose weight without the need to fast.
Of course, keep in mind that we  need to burn 9,000 calories to lose a single kilo of fat.
Starting a diet that is too draconian can end up being harmful to our health, since we will later suffer the yo-yo effect.
It is better to eliminate 500 calories from our daily intake to lose a few kilos in a month than to do high intensity exercise to lose 5,000 calories that we will later regain in the blink of an eye.
To lose weight quickly, we must consume foods rich in vitamins and minerals, and not starve between meals: cucumber, eggplant, tomato, zucchini, carrot, cabbage, leek, skimmed dairy products, legumes and white meats, water, green tea, etc. . Everything to follow a fully balanced hypocaloric diet. How many calories a day do I have to lose to lose weight?