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close this bookProtein-Energy Requirements of Developing Countries: Evaluation of New Data (UNU, 1981, 268 p.)
close this folderProtein requirements-children
close this folderProtein requirements of pre-school children: milk and soybean protein isolate
View the document(introduction...)
View the documentObjectives
View the documentExperimental details
View the documentSummary of main results
View the documentConclusions


1. The mean nitrogen requirements, allowing for integumental losses and nitrogen retention for growth, were 98 mg (0.61 9 protein) of milk/kg/day and 120 mg (0.75 9 protein) of soybean isolate/kg/day. The milk requirement is 33 per cent lower than the estimate made by the FAD/WHO Committee of Experts on Energy and Protein Requirements (WHO Tech. Rep. Ser. No. 522, 1973).

2. The coefficients of variation between individuals of the regression coefficients and of the nitrogen requirements for the two protein sources were between 14 and 16 per cent, except for the mean nitrogen requirement with milk, which was 28 per cent. If two children with high requirements were excluded, variability would be reduced to 16 per cent. The safe levels of intake of the two proteins can be calculated by adding 30 per cent to the mean requirements (FAO/WHO, 1973), or by using the higher limit of the 95 per cent confidence bands (Rand et al., Am. J. Clin. Nutr., 30: 1129 [1977] ). With the former approach, they would be 127 mg nitrogen or 0.79 9 protein/ kg/day for milk, and 156 mg nitrogen or 0.98 9 protein/kg/day for soybean protein isolate. Using the confidence bands, they are 151 mg nitrogen or 0.94 9 protein/kg/day for milk, and 162 mg nitrogen or 1.01 9 protein/kg/day for the soybean isolate. All of these values are lower than the 1.19 9 milk protein/kg/day suggested by FAD/WHO

3. The nutritive value of the soybean protein isolate was 82 per cent relative to milk.


The Ralston-Purina Company provided us with the milk, soybean protein isolate, and other materials used in these studies. Ms. Cabrera-Santiago participated in the investigation under a Fellowship from the United Nations University World Hunger Programme.