Nitrogen retention and plasma amino acids of men who consumed isonitrogenous diets containing egg albumen or mixtures of amino acids.

Experimental diets that furnished approximately 6.0 g of nitrogen per day were consumed by young men. Nitrogen retention was not altered significantly when egg albumen was replaced by its constituent essential and nonessential amino acids or by the essential amino acids (including cystine, tyrosine and histidine) plus a source of nonspecific nitrogen. Concentrations of essential amino acids in fasting or postprandial plasma were not influenced significantly by source of amino acids or by replacement of nonessential amino acids by nonspecific nitrogen; but concentrations of certain nonessential amino acids were altered by treatment. Responses to an elemental diet or to a similar diet in which egg albumen replaced the amino acid mixture did not differ significantly.