Manary Mark J, Wegner Donna R, Maleta Kenneth
Department of Pediatrics, Washington University, St. Louis, MO, United States.
Children's Nutrition Research Center, USDA, Houston, TX, United States.
Front Nutr. 2024 Oct 23;11:1428810. doi: 10.3389/fnut.2024.1428810. eCollection 2024.
Protein quality refers to the evaluation of a food or a diet based on its amino acid composition, protein digestibility, and protein bioavailability. When these parameters are specified, either through direct measurement or estimation, the amino acids provided by the diet are compared to those required by a healthy individual, and based on this comparison, an adequacy ratio or score is assigned. Two widely used protein quality scoring systems are the protein digestibility-corrected amino acid score (PDCAAS) and the digestible indispensable amino acid score (DIAAS), neither of which account for the dietary source of the protein. In malnourished children, metabolic adaptations reduce the endogenous availability of amino acids and increase the demand for protein synthesis. These increased amino acid requirements are primarily driven by the presence of acute infection and the need for tissue accretion. This review examines two large clinical feeding trials involving moderately malnourished children, where dietary protein quality was carefully measured. The finding s suggest that protein quality scores alone do not reliably predict weight gain or recovery in these children and that consuming milk protein provides distinct advantages over vegetable-based proteins.
蛋白质质量是指基于食物或饮食的氨基酸组成、蛋白质消化率和蛋白质生物利用率对其进行的评估。当通过直接测量或估算确定这些参数后,将饮食提供的氨基酸与健康个体所需的氨基酸进行比较,并基于此比较得出充足率或分数。两种广泛使用的蛋白质质量评分系统是蛋白质消化率校正氨基酸评分(PDCAAS)和可消化必需氨基酸评分(DIAAS),这两种评分系统均未考虑蛋白质的饮食来源。在营养不良的儿童中,代谢适应会降低氨基酸的内源性可用性,并增加蛋白质合成的需求。这些增加的氨基酸需求主要由急性感染的存在和组织生长的需要驱动。本综述考察了两项涉及中度营养不良儿童的大型临床喂养试验,其中对饮食蛋白质质量进行了仔细测量。研究结果表明,仅蛋白质质量评分并不能可靠地预测这些儿童的体重增加或恢复情况,并且食用乳类蛋白比植物性蛋白具有明显优势。