Weekly cholecalciferol supplementation results in significant reductions in infection risk among the vitamin D deficient: Results from the CIPRIS pilot RCT

Abstract

Background: Observational studies suggest vitamin D deficiency may contribute to the risk of acute infections. We undertook a randomised controlled trial (RCT) of cholecalciferol supplementation as an intervention against acute infections. Methods: A cohort of 34 healthy adults was randomised to 20,000 IU/week cholecalciferol or identical placebo and followed for 17 weeks during winter 2012. Acute infections, defined as the occurrence of sustained (at least an hour) infection symptoms, either of severity 2/5 or greater or sustained over 24 h, were monitored by daily online symptom reporting, with potential infections assessed in clinic. No microbiological verification of symptoms was availab..