Lesourd B M
Laboratoire d'Immunologie du vieillissement, Faculté de Médecine Pitié-Salpétrière, Paris, France.
Am J Clin Nutr. 1997 Aug;66(2):478S-484S. doi: 10.1093/ajcn/66.2.478S.
Nutrition has a strong influence on the immune system of the elderly. Aging induces dysregulation of the immune system, mainly as a result of changes in cell-mediated immunity. Aging is associated with changes to the equilibrium of peripheral T and B lymphocyte subsets, such as decreases in the ratios of mature to immature, naive to memory, T helper 1 subset (TH1) to TH2, and CD5- to CD5+ cells. As a consequence, cell-mediated immune responses are weaker and neither cell-mediated nor humoral responses are as well adapted to the antigen stimulus. Undernutrition, common in aged populations, also induces lower immune responses, particularly in cell-mediated immunity. Protein-energy malnutrition is associated with decreased lymphocyte proliferation, reduced cytokine release, and lower antibody response to vaccines. Micronutrient deficits, namely of zinc, selenium, and vitamin B-6, all of which are prevalent in aged populations, have the same influence on immune responses. Because aging and malnutrition exert cumulative influences on immune responses, many elderly people have poor cell-mediated immune responses and are therefore at a high risk of infection. Nutritional therapy may improve immune responses of elderly patients with protein-energy malnutrition. Supplementation with high pharmacologic doses of a single nutrient (zinc or vitamin E) may be useful for improving immune responses of self-sufficient elderly people living at home. Therefore, nutritional deficiency must be treated in the elderly to reduce infectious risk and possibly slow the aging process.
营养对老年人的免疫系统有很大影响。衰老会导致免疫系统失调，主要是细胞介导免疫发生变化所致。衰老与外周T和B淋巴细胞亚群的平衡改变有关，例如成熟与未成熟、初始与记忆、辅助性T细胞1亚群（TH1）与TH2以及CD5 -与CD5 +细胞比例的下降。因此，细胞介导的免疫反应较弱，细胞介导和体液反应对抗原刺激的适应性都较差。营养不良在老年人群中很常见，也会导致免疫反应降低，尤其是在细胞介导免疫方面。蛋白质 - 能量营养不良与淋巴细胞增殖减少、细胞因子释放降低以及对疫苗的抗体反应减弱有关。微量营养素缺乏，即锌、硒和维生素B - 6缺乏，在老年人群中都很普遍，并对免疫反应有同样的影响。由于衰老和营养不良对免疫反应产生累积影响，许多老年人的细胞介导免疫反应较差，因此感染风险很高。营养治疗可能会改善蛋白质 - 能量营养不良老年患者的免疫反应。补充高药理剂量的单一营养素（锌或维生素E）可能有助于改善居家生活的自给自足老年人的免疫反应。因此，必须治疗老年人的营养缺乏问题，以降低感染风险，并可能延缓衰老过程。
