The immune system's major functions are to defend the host from infection by pathogenic microbes, to clear damaged tissues, and to keep an eye on cancerous cells that proliferate within the body. Nutrition has been investigated as a changeable component in immune function for several decades, and the discipline has evolved into a renowned study subject known as nutritional immunology. The immune system, like other physiological systems, relies on enough nutrition to function correctly. Nutritional status is well-documented as being linked to immunity and host resistance to infection. Nutrition is essential for immunological defence and pathogen resistance, with repercussions that affect individual organisms' health, welfare, and reproductive success, as well as having significant ecological and evolutionary ramifications. Increased intake of some nutrients above currently recommended levels may assist optimize immunological activities, such as enhancing defensive mechanisms and consequently infection resistance, while preserving tolerance, according to growing research.