Zinc deficiency and supplementation in HIV/AIDS

Abstract

Zinc is an essential micronutrient and deficiency is associated with immunoparesis, an increased susceptibility to infections, and slower growth in children. Supplementation reduces the incidence and severity of diarrhoea and lower respiratory tract infections, decreases morbidity and mortality in malaria, and may contribute to improvement in neuropsychological performance and growth. This review examines the potential of zinc to ameliorate HIV disease in children and adults. A summary of the published articles demonstrates that the data is insufficient or flawed to explore this fully. The available data on zinc and immunity suggest that deficiency of the ion may increase HIV replication, impair cellular immunity, and accelerate apoptosis of cells involved in the immune responses. However there is a paucity of data on the effect of zinc supplementation in HIV-infected children. From the available studies in children, it seems that there is no significant deficiency of zinc in HIV infection, no association between zinc levels and disease progression, and little benefit from supplementation. More information is available on zinc and HIV in adults. This shows that the effects of zinc deficiency are inconsistent in seropositive adults, but may include an increase in viral load, lower CD4 numbers, and higher mortality. Zinc supplementation has not been shown to be beneficial in HIV-infected adults or children, and excess zinc supplements may, in fact, be harmful to both children and adults.Accordingly we find that there is no firm evidence that zinc supplementation may be of benefit in improving health or ameliorating disease in HIV-infected children and adults. Well designed trials to test the effects of zinc supplementation in HIV-infected individuals are required; the consequences of zinc deficiency and supplementation on elements of the immune response critical to HIV infection should be examined.