Markers of Innate Immune Function Are Associated with Vitamin A Stores in Men

Recommendations for vitamin A intake and liver stores are based on maintaining normal vision. We propose that higher levels may be required to maintain normal innate immune function. To test this hypothesis, we conducted an 8-wk residential study among 36 healthy Bangladeshi men with low vitamin A stores. Subjects were randomized to receive vitamin A (240 mg in 4 doses) or placebo during study wk 2 and 3. They received 2 vaccines during wk 5 and vitamin A stores were estimated by isotopic dilution at wk 8. The serum concentration of the chemokine interferon-gamma-induced protein 10, a component of T-helper 1 (Th1) response, increased significantly after supplementation and was positively and significantly associated with vitamin A stores. Blood concentrations of…