The diet intake especially in the elderly people does not provide an adequate level of nutrients that is required to maintain a satisfactory healthy status. It could be due to the micronutrient deficiencies and impaired immune response with consequent development of degenerative diseases. Nutrient "zinc" is a significant micronutrient, which is involved in maintaining a good integrity of various body homeostatic mechanisms, including immune efficiency. It is required for the biological activity of several enzymes, proteins and for cellular proliferation and genomic stability.

Elderly individuals aged 60-65 years and/or older have zinc intakes less than 50% of the recommended daily allowance on a given day. Several causes can be involved such as altered intestinal absorption, psychosocial factors, inadequate mastication, drug interactions, and altered subcellular processes [zinc transporters (Zip and ZnT family), metallothioneins, and divalent metal transporter-1].

Supplementation of zinc may modify the immune alterations in elderly individuals resulting in healthy ageing. Numerous zinc trials have been carried out with differing data, possibly due to inappropriate choice of an effective zinc supplementation in old participants showing subsequent zinc toxic effects on immunity. Old individuals with specific IL-6 polymorphism, i.e. GG allele carriers, are more inclined to zinc supplementation than the whole old population, in whom the right dietary habits with foods containing zinc (i.e. Mediterranean diet) might be enough in restoring zinc deficiency and impaired immune response.

Source: Mocchegiani E, Romeo J, Malavolta M, et al. Zinc: dietary intake and impact of supplementation on immune function in elderly. Age (Dordr). 2013; 35(3):839-860. doi:10.1007/s11357-011-9377-3