What is a calorie?

Calorie - is a measure of heat. One of calorie is enough heat to make a kilogram of water one degree Centigrade hotter. The energy which drives the human body is also measured in calories. When people talk about the calorific value of food, they are referring to the amount of energy it gives the person who eats it. The amount of energy a person uses decides the amount of food needed. It depends on how big a person is and how much exercise is taken. A big, muscular lumberjack needs more than 2,500 calories a day, while a small secretary, who sits at a desk all the time, cannot take in more than 1,400 a day without getting fatter. Children need more calories for their size than adults because growing uses up energy fast. When people put on weight it is because they are taking in more calories than they are using up in energy, and the extra is being stored as fat. The reverse is also true. Calorific value is not the same as nutritional value. The body also needs special kinds of food to keep healthy. So people who are trying to lose weight must still eat a good deal of meat, or other form of protein, and vegetables. If they cut these out, their bodies will be undernourished and vulnerable to illness.