MICRONUTRIENTS AND THE IMMUNE SYSTEM.

Prof. R.K. Chandra, Memorial University of

Newfoundland, St. John's, A1B 3V6, Canada.

Nutrition is a critical determinant of immunity and

risk of infection. The major effects of nutritional

deficiencies include impairment of cell‑mediated

immunity, phagocyte dysfunction, reduction in

complement levels and activity, mucosal IgA antibody

response, decreased production of cytokines, and

antibody affinity.

In addition to protein‑energy malnutrition, many

individual nutrients influence immune responses. These

include zinc, iuron, selenium, copper, vitamins A, E,

C, B6 and folic acid. Some of these act

synergistically, for example vitamin E and selenium.

Excess intake of several nutrients also impairs immune

responses; therefore, moderation is the key word for

nutrition‑immunity interactions. This has several

practical and clinical applications for individual and

public health.