Abstract
A growing body of evidence from cross-sectional epidemiologic studies has shown that HIV-infected persons and AIDS patients exhibit abnormal blood levels of key micro-nutrients and sulphated amino acids (thiols) that are prevalent early in infection. The abnormalities appear to arise from an interplay of malnutrition, malabsorption, metabolic alteration and nutrient depletion associated with the risk factors of HIV infection. The nutrients in question include vitamins A, B-complex, C, E and carotenes (precursor of vitamin A); trace elements selenium, copper and zinc; and thiols, namely, cysteine and the tripeptide glutathione (GSH). Most of these compounds are well known in providing protective physiologic functions, serving as vital antioxidants in scavenging toxic free radicals and/or as immunomodulators in maintaining cell-mediated/humoral responses. Some B-complex nutrients (namely, B6 and B12) have been linked to maintenance of cognitive functions. Therefore, micro-nutrient imbalance may contribute to increased oxidative stress/inflammation and abnormalities in immunologic/neurophysiologic functions underlying HIV/AIDS. Additionally, specific antioxidants (notably vitamin C, selenium and cysteine) have been demonstrated to suppress HIV replication and virus activation in infected cells. Accordingly, deficiencies in these physiologic antioxidants may potentiate HIV replication and exacerbate the pathological effects (including lymphocyte depletion) associated with HIV-induced chronic immune activation/inflammation. Evidence from prospective studies in asymptomatic HTV-seropositive persons has demonstrated that micro-nutrient consumption or multi-vitamin use at baseline was associated with significant reduction in rate of progression to AIDS. Nutritional intervention studies evaluating efficacy of high micro-nutrient supplementation in randomized cohorts are required to validate conclusively the influence of nutritional factors on AIDS progression.