Micronutrients and innate immunity

folic acid can in¯uence several components of innate immunity. Select micronutrients play an important role in alteration of oxidant-mediated tissue injury, and phagocytic cells produce reactive oxidants as part of the defense against infectious agents. Thus, adequate micronu-trients are required to prevent damage of cells participating in innate immunity. De®ciencies in zinc and vitamins A and D may reduce natural killer cell function, whereas supplemental zinc or vitamin C may enhance their activity. The speci®c effects of micronutrients on neu-trophil functions are not clear. Select micronutrients may play a role in innate immunity associated with some disease processes. Future studies should focus on issues such as age-related micronutrient status and innate immunity, alterations of micronutrients in disease states and their effect on innate immunity, and the mechanisms by which micronutrients alter innate immunity. Nonspeci®c, innate, or natural immunity is present from birth and comprises components that serve as defense barriers. The innate immune system can play an important role as the ®rst-line defense or barrier against foreign organisms and sub