Vitamin nutritional status and immunocompetence of elderly in Perugia (Italy): an epidemiological approach.

The influence of the vitamin nutritional status on the immunocompetence of a group of elderly people in the city of Perugia has been investigated. The impairment of some immunological (humoral as well as innate and acquired cell-mediated) functions seemed to be mostly related to age. Statistically significant correlations between the complement component C4 and plasma levels of retinol as well as alpha-tocopherol and an inverse correlation between titers of IgG and plasma retinol have been observed (significance level alpha = 5%).