Nitrogen retention of young men fed rice with or without supplementary chicken

Abstract
Two levels of nitrogen, 8.0 and 6.0 g, from rice only or from rice plus chicken, were tested in six healthy young men. At each level of nitrogen, three treatments were studied: 100% of nitrogen from rice only, 85% from rice plus 15% from chicken, and 70% from rice plus 30% from chicken. A cross-over design was used. Mean daily nitrogen balances were 1.07, 0.89, and 1.04 g, respectively, when rice supplied 100, 85, and 70% of 8.0 g nitrogen, and 0.18, 0.39, and 0.30 g when 6.0 g nitrogen were consumed. The effect of total nitrogen level on nitrogen retention was significant (P < 0.01). The fact that partial substitution of chicken for rice did not exert a statistically significant effect can be attributed to the relatively high intake of lysine when rice supplied either 8.0 or 6.0 g nitrogen. All subjects were in positive balance when they consumed 8.0 g nitrogen from 595 g rice alone but only half of them when 446 g rice supplied 6.0 g nitrogen.