Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren

To our knowledge, no rigorously designed clinical trials have evaluated the relation between vitamin D and physician-diagnosed seasonal influenza.We investigated the effect of vitamin D supplements on the incidence of seasonal influenza A in schoolchildren.From December 2008 through March 2009, we conducted a randomized, double-blind, placebo-controlled trial comparing vitamin D(3) supplements (1200 IU/d) with placebo in schoolchildren. The...