Iron, folacin, vitamin B12 and zinc status and immune response in the elderly

The relationships of iron, folacin, vitamin B12 and zinc status to cell-mediated immune response were investigated among 125 healthy, elderly persons (60-87 years of age). Plasma ferritin, plasma and red cell folate, and plasma vitamin B12 levels were assayed immuno-radiometrically. Plasma and hair zinc levels were determined by atomic absorption spectroscopy. Immune response was determined by transformation of peripheral blood lymphocytes after stimulation with phytohemagglutinin (PHA) and concanavalin A (con A), and in mixed lymphocyte reaction. Deficiencies of iron, folacin vitamin B12 and zinc were each associated (independently) with significantly lower lymphocyte responses to PHA and con A, and mixed lymphocyte reaction (P < 0.01). These findings indicate a depression of cell-mediated immunity in elderly persons deficient in iron, folacin, vitamin B12 or zinc. Further, they suggest that deficiencies of these nutrients may play a role in the depression of cell-mediated immunity with age, which in turn may lead to increased susceptibility to infectious diseases and cancer in the elderly