Vitamin D, acute respiratory infections, and Covid-19: The curse of small-size randomised trials. A critical review with meta-analysis of randomised trials.
BackgroundRandomised trials conducted from 2006 to 2021 indicated that vitamin D supplementation (VDS) was able to prevent severe COVID-19 and acute respiratory infections (ARI).However, larger randomised trials published in 2022 did not confirm the health benefits of VDS in COVID-19 patients.ObjectiveTo examine through a systematic review with met