Nitrogen Balances of Women Maintained on Various Levels of Methionine and Cystine

Abstract

With a cystine intake of 500 mg, 150 to 180 mg of methionine resulted in nitrogen storage in 4 of 7 women, while the balances of the other three were within the “zone of equilibrium.” An intake of 290 mg appeared to be adequate for all 13 subjects studied at those levels. A total of 300 mg of the two sulfur-containing amino acids appeared to be marginal while 550 mg resulted in some nitrogen storage in all subjects. From these data it appears that a total of 550 mg of the sulfur-containing amino acids is adequate for the establishment of nitrogen balance in women, under these conditions.