Calorie intake should be kept at a lower level than the amount of calories we spend a day, if we want to reduce weight. If we have an unhealthy diet, we are left with excess calories that do not burn.
Then, the excess energy turns into fatty tissue. The excess calories that the body does not exploit are being stored as fat.
A general rule is that if you enter 500 calories less than you need a day, you will lose about half a kilogram of your weight per week. How many calories you need depends on valid lifestyle and other factors.
There are various methods for determining the daily caloric needs. One of the methods for determining the daily caloric needs is the relatively precise Harris-Benedict –This is mathematical equation that includes body height, weight, age and gender. But here we will give a simpler example.
Usually in women the need for calories can be relatively accurately calculated with using the two calorie components, and they are: the basal metabolism (BMR — Basal Metabolic Rate) and physical activity.
Most of us know that weight depends on the equation of energy balance: the amount of energy that we enter in the body (calories from food) in ratio with the amount of energy that is wasted (activity).