The Nitrogen Metabolism in Infants on Graded Intake of Soybean “Milk” Proteins.

Abstract

The soybean “milk” with certain non-protein additions has been successfully employed in the feeding of young infants. 1 In general the proteins are fed on a high level constituting approximately 20% of the caloric intake in contrast to the usual 12 to 15% in case of cow's milk and 8% human milk proteins. The nitrogen metabolism was followed in 2 male infants 4 and 7 months old who were given soybean “milk” formulae furnishing approximately 18.5, 13.5, 10.5 and 8.5% protein calories respectively but the same number of total calories per kilo of body weight. In one period cow's milk protein was fed at 12.2% level of calorie intake. The results were:

1. At each of the graded levels of protein intake the nitrogen balance was positive. But the higher the protein intake the larger was its retention.

2. Retention was better on 12.2% calorie intake in cow's milk proteins than on 18.5% of soybean “milk” protein calories.

3. Within the limits studied, the ratio of soybean “milk” nitrogen absorbed to the nitrogen ingested seems fairly constant. The soybean nitrogen absorption was distinctly lower than in the case of cow's milk nitrogen.