Respiratory-tract infections and asthma are major health concerns in early childhood, causing significant morbidity and long-term complications. Asthma, the most common chronic childhood condition, is often triggered by respiratory infections. With rising prevalence rates, prevention is critical. Vitamin D, known for its immunoregulatory properties and effects on inflammation and pathogen defense, has been identified as a potential modulator. Observational studies link low maternal and early-life vitamin D levels to higher infection susceptibility and asthma risk.

Vitamin D may reduce asthma and infection risk by modulating airway immunity, microbiota composition, systemic inflammation, and sphingolipid metabolism. Prenatal supplementation has shown promise in altering infant immune profiles and microbiota, potentially reducing asthma risk. However, direct evidence for preventing respiratory infections or asthma is mixed, emphasizing the need for robust, large-scale trials. Future research should focus on optimal dosing, genetic factors, and long-term interventions to better define vitamin D’s role in prevention. Understanding its mechanisms and refining prevention strategies remain vital to reducing childhood respiratory diseases.

Reference: Brustad N, Chawes B. Vitamin D Primary Prevention of Respiratory Infections and Asthma in Early Childhood: Evidence and Mechanisms. J Allergy Clin Immunol Pract. 2024 Jul;12(7):1707-1714. doi: 10.1016/j.jaip.2024.02.005. Epub 2024 Feb 14. PMID: 38360214.
Link:
https://pubmed.ncbi.nlm.nih.gov/38360214/