Ann Bondowski, age 13, of Freeport, 111. for her question:

CAN RICKETS BE PREVENTED?

Rickets is a bone disease that occurs mostly in children under 3 years of age. It may be caused by a lack of calcium and vitamin D or by the inability of the body to use those substances properly. The bones are so soft that they bend into abnormal shapes.

Eating foods that are rich in calcium and vitamin D usually prevents rickets. Calcium can be obtained by drinking plenty of milk and eating green vegetables every day. The best sources of vitamin D are sunlight and fish oils.

A child can sometimes be cured of rickets by exposing him to plenty of sunlight and by giving him substances rich in vitamin D, such as cod liver oil or halibut liver oil.

Rickets results in conditions called bowlegs, knock knees, chicken breast, funnel chest, rosary ribs and knobbed forehead. As the child grows, bones harden, but the abnormal shape usually remains.

Some of the symptoms of rickets are sweating, especially on the head, weakness, flabbiness, pain in the bones and misshapen bones. Doctors use X rays to diagnose rickets.