Nitrogen balance and calorie efficiency in small-for-date dwarfism.

Accelerated weight gain was induced in eight infants, including two patients with dwarfing syndromes, who were small for their dates of birth and continued to be small after birth. The calorie cost of weight gain was higher than in control infants with linear growth failure due to undernutrition, but the degree of inefficiency did not seem to be of practical significance. Nitrogen retentions were appropriate for weight gain or better. Nitrogen retentions in excess of those expected on the basis of weight gain were seen in infants with small-for-date dwarfism and in controls when calorie intakes were low. The ability to induce good nitrogen retentions is thus no reflection of linear growth potential.