John Cooper, Jr. age 15, of Decatur I11., for his question:

HOW MANY CALORIES DOES A PERSON NEED EACH DAY?

Calories are units of energy supplied by food. The amount of calories a person needs each day depends on the person's sex, age, body build and degree of physical activity.

Children and young people up to 19 years of age require an average of 820 to 3,070 calories each day, depending on age, weight and sex. A husky girl or boy who is a member of all the school's athletic teams needs more calories than does a slightly built, inactive student.

It is estimated that a moderately active man of average weight needs about 3,000 calories each day. A moderately active woman of average weight needs about 2,200.

Daily calories intake by all people in the poorest developing countries average under 2,000 calories, according to United Nations estimates. This is far less than most people require. In many developed countries, daily calorie consumption averages over 3,200. This is far more than most people require.