Abstract
Recent years have seen a search for more effective forms of asthma therapy, with one possible option being vitamin D supplementation. The main objective of this study was to present the current state of knowledge on the effect of vitamin D supplementation on the course of asthma in children and adults; it also reviews the existing literature on prenatal vitamin D supplementation and asthma status. The search comprised articles, mostly randomized controlled trials (RCTs), included in the PubMed database and published after 2018. Most RCTs conducted on children indicate that vitamin supplementation did not affect the course of the disease, its control, or exacerbations; however, several trials in adults confirm it to have beneficial effects, with an important role being played by vitamin D deficiency. Unfortunately, the studies demonstrated considerable heterogeneity concerning the age and number of participants, dose, duration, and use of guidelines for pharmaceutical drugs, making it difficult to draw clear conclusions. Further, properly designed, large-scale studies with long-term follow-ups are needed.