The nutritional state and nutrition.

Cystic fibrosis children tend to have a low birth weight and their mean height and weight during childhood is below that for the general population. They also tend to have a delayed bone age and puberty. The degree of underweight correlates more closely with the respiratory condition than with the degree of malabsorption. There is evidence that their nutritional requirements are increased, perhaps up to 150% of the recommended daily allowance, but in later childhood their food intake is frequently low and maybe the major reasons for their poor growth and development. Specific deficiencies of vitamins, minerals and essential fatty acids occasionally present as clinical problems. New approaches to nutrition include increasing dietary fat, which was traditionally low because of malabsorption, and this change has been made possible with the development of modern pancreatic supplements. Supplementary nutrition with elemental diets or intravenous hyperalimentation have given promising results in some studies and might be expected to improve the patient's resistance to infection as well as his nutritional state. The place of oral essential fatty acid supplements is still being evaluated, but intravenous infusions of fat emulsion are not justifiable in themselves.