Your body needs energy, protein, mineral, vitamins, and fiber. In order to get all of these, it is important to have a varied and balanced diet, and to eat the right the amount of food.Your body 'burns' food to energy: the amount of ebergy provided by food is measured in unit called calories.

How many calories do dou need? The depends on your weight and what you do. When you are asleep, your body uses nearly one calorie an hour for every kilogram of weight.So a personwho weighs seventy kilos, used about 560 calories while sleeping for eight hour. More calories are needed for different activities-from 1000 calories an hour for reading or wathcing TV, to 350 calories an hour for palying football.
To calculate the number of calories needed per day for an average person, find out the person's ideal weight. Ten multipy the weight by 40 for a women and 46 for a man. A 60-kilo woman may need about 2400 calories a day-mmore if she does heavy physical work and less if she is very inactive