本研究估计了12～14岁青春期男孩蛋白质需要量以及混合膳食满足其需要量的能力。8名12～14岁健康男孩自愿参加本研究。使用两种膳食:一种为蛋白质摄入量分4个水平的实验混合蛋白质膳食,蛋白质水平为0.45、0.65、0.85和1.05/kg体重·d,相当于72、104、136和168mgN/kg体重·d;另一种为对照参考蛋白质膳食(奶和蛋),蛋白质为1.0g/kg体重·d,相当于160mgN/kg体重·d。实验混合蛋白质膳食的每个水平实验期均为10d,前5d为适应期,后5d为实际平衡期。在混合蛋白质膳食结束时,让受试者进食由奶蛋各半组成的对照参考蛋白质膳食。实验持续总日 This study estimated the protein requirements of adolescent boys aged 12-14 and the ability of a mixed diet to meet their needs. Eight healthy boys aged 12 to 14 volunteered to participate in this study. Two diets were used: an experimental mixed protein diet divided by 4 levels for protein intake at protein levels of 0.45, 0.65, 0.85 and 1.05 / kg body weight · d, corresponding to 72, 104, 136 and 168 mg N / kg body weight · D; the other for the control reference protein diet (milk and egg), protein 1.0g / kg body weight · d, equivalent to 160mgN / kg body weight · d. The experimental mixed protein diet for each level of the experimental period were 10d, 5d before the adaptation period, 5d after the actual balance. At the end of the mixed protein diet, subjects were asked to eat a control reference protein diet consisting of half the custard. The experiment lasts for a total of days