美国人饮食指南(DGA)发布了“盎司当量”建议,以帮助消费者满足各种蛋白质食物来源的蛋白质需求。然而,这些不同蛋白质食物来源的代谢当量尚未确定。
我们已经研究了以下假设:对消耗盎司当量的蛋白质食物来源的合成代谢反应将与蛋白质食物来源的必需氨基酸(EAA)含量直接相关。
饮食控制3天后,使用稳定同位素示踪方法,共有56名健康年轻人接受了8.5小时的代谢研究.将消耗7种不同蛋白质食物来源中的一种后的基线变化与该个体的基线值进行比较(每组n=8)。
消费盎司当量的动物性蛋白质食物来源(牛油,猪腰,鸡蛋)导致在高于基线的全身净蛋白质平衡中获得更大的增益,而不是以植物为基础的蛋白质食物来源的盎司当量(豆腐,芸豆,花生酱,混合坚果;P<0.01)。全身净蛋白质平衡的改善是由于所有动物蛋白质来源的蛋白质合成增加(P<0.05),与植物蛋白来源相比,鸡蛋和猪肉组也抑制了蛋白质分解(P<0.01)。全身净平衡(合成代谢)反应的大小与蛋白质食物来源的EAA含量相关(P<0.001)。
在DGA中表示的蛋白质食物来源的“盎司当量”在年轻健康个体中代谢不相等。随着DGA开发建立健康饮食模式的方法,应考虑对饮食蛋白质的合成代谢反应的幅度。
The Dietary
Guidelines for Americans (DGAs) published an \"ounce equivalents\" recommendation to help consumers meet protein requirements with a variety of protein food sources. However, the metabolic equivalency of these varied protein food sources has not been established.
We have investigated the hypothesis that the anabolic responses to consumption of ounce equivalents of protein food sources would be directly related to the essential amino acid (EAA) content of the protein food source.
Following 3 d of dietary control, a total of 56 healthy young adults underwent an 8.5-h metabolic study using stable isotope tracer methodology. The changes from baseline following consumption of 1 of 7 different protein food sources were compared with the baseline value for that individual (n = 8 per group).
Consumption of ounce equivalents of animal-based protein food sources (beef sirloin, pork loin, eggs) resulted in a greater gain in whole-body net protein balance above baseline than the ounce equivalents of plant-based protein food sources (tofu, kidney beans, peanut butter, mixed nuts; P < 0.01). The improvement in whole-body net protein balance was due to an increase in protein synthesis (P < 0.05) with all the animal protein sources, whereas the egg and pork groups also suppressed protein breakdown compared with the plant protein sources (P < 0.01). The magnitude of the whole-body net balance (anabolic) response was correlated with the EAA content of the protein food source (P < 0.001).
The \"ounce equivalents\" of protein food sources as expressed in the DGAs are not metabolically equivalent in young healthy individuals. The magnitude of anabolic response to dietary proteins should be considered as the DGAs develop approaches to establish healthy eating patterns.