Vitamin A

A deficiency of vitamin A is associated with increased morbidity and mortality, most likely because of increased severity of infections [85].Vita-min A and related retinoids maintain the integrity of epithelial boundaries and the production of mucosal secretions. Some of the immunological abnormalities following vitamin A inadequacies include a reduced number of leukocytes, reduced lymphoid organ weights, reduced circulating levels of complement, impaired T-cell functions, and decreased resistance to immunogenic tumours.

Vitamin A supplementation studies showed decreases in respiratory infections and neutrophil counts and increases in reticuloendothelial system function, lymphocyte proliferation, tumour resistance, graft rejection and cytotoxic T-cell activities. Supplementation above that required to maintain normal vitamin A stores results in adjuvant effects. Excess vitamin A increases antibody and cell-mediated immune responses, stimulates Kupffer cells and potentiates some types of liver toxicity and gouty arthritis [86]. The inhibition of T-cell apoptosis by retinoic acid may contribute to its adjuvant effect [87].

The vitamin A precursor p-carotene is generally considered an antioxidant with activities that are independent of its provitamin A function. Some of its reported benefits include protecting host cells and tissues from oxidation by the respiratory burst and promoting lymphocyte proliferation, T-cell functions, cytokine production and cell-mediated cytotoxicity. However, Bates [88] cautioned that carotenoids can exhibit both pro-oxidant and antioxidant activity.

Arthritis Relief and Prevention

Arthritis Relief and Prevention

This report may be oh so welcome especially if theres no doctor in the house Take Charge of Your Arthritis Now in less than 5-Minutes the time it takes to make an appointment with your healthcare provider Could you use some help understanding arthritis Maybe a little gentle, bedside manner in your battle for joint pain relief would be great Well, even if you are not sure if arthritis is the issue with you or your friend or loved one.

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