The relationship between nutrition and infectious diseases: A review

Abstract
Nutrition and infectious diseases are related to each other in some aspects. First, nutrition affects the development of human body immune system. Moreover, nutrition can influence emerge of infectious diseases (e.g., gastrointestinal infections), food poisoning, intestinal diseases, and systemic infectious diseases. In this review, the mentioned aspects of the relationship between nutrition and infections are discussed. Furthermore, the relationship between malnutrition and infectious diseases, nutrition in patients with severe combined immunodeficiency and relationship between overeating and infection are reviewed. Overall, some factors can weaken the body's ability to fight infection and cause malnutrition. The factors include anorexia, traditional behaviors, reduction of intestinal absorption, metabolic damage, disorder metabolism of lipids and carbohydrates, reduction of vitamins, iron, zinc, and copper. In the case of the relationship between malnutrition and infection, a large number of studies have illustrated a bidirectional interaction of malnutrition and infection. In this aspect, to treat serious acute malnutrition and limit the rate of death, some preventive studies applied antibiotics, probiotic bacteria, and prebiotic foods. In the future, studies may be conducted on intestinal or systematic immunomodulation.