Influence of dietary pattern on human immunity

Abstract

Objective: To systematically review the relationship between dietary patterns and human immunity and health. Methods: Chinese and English search terms, including "dietary pattern", "dietary structure", "nutrients", "food", "protein", "fat", "vitamins", "dietary fiber", "immunity", "inflammatory", "inflammation", "oxidative stress", were searched for relevant articles in PubMed, Web of Science, Wanfang and National Knowledge Infrastructure (CNKI) database from the collection start date to January 10, 2020. Results: A total of 1 Chinese article and 22 English articles were included, including 9 cross-sectional studies, 7 intervention studies, 6 cohort studies and 1 nested case-control study. Common evaluation methods for dietary patterns included dietary inflammatory index (DII), inflammatory score of the diet (ISD), empirical dietary inflammatory pattern (EDIP), dietary compliance score, and healthy eating index. There were 13 studies on Mediterranean dietary patterns and healthy dietary patterns with higher intake of vegetables, fruits, bean products, fish and dairy products in the included articles. The Mediterranean diet can reduce the levels of inflammatory markers such as CRP, IL-6, Hcy, WBC, and fibrinogen, as well as the levels of metabolic indicators such as vascular endothelial growth factor and endothelial function score, improve chronic inflammatory diseases and reduce the risk of chronic diseases. The higher the healthy diet score was, the lower the level of pro-inflammatory factors was. Even if the dietary recommendation was not met, the healthier the diet was, the lower the level of inflammatory factors was. Western dietary patterns were positively correlated with CRP, IL-6, E-selectin, sICAM-1, sVCAM-1 and other inflammatory factors, and can increase the incidence of type 2 diabetes and the risk of cardiovascular disease. However, one study did not found the relationship between them and hs-CRP. Conclusions: Dietary patterns are closely related to human immune function. Different dietary patterns have different inflammatory potentials according to the characteristics of food intake, which can directly or indirectly affect immune function.