This randomized trial included 130 patients with asthma aged 10 to 50 years from Iran during a 6-month period. Vitamin D was measured before, and 4 and 6 months after the intervention. Patients were divided in 2 groups randomly. Both groups received asthma controllers (budesonide or budesonide plus formoterol) according to their stage. The intervention group received vitamin D supplementation (100,000-U bolus intramuscularly plus 50,000 U orally weekly).
FEV1 was significantly better in the intervention group after 6 months. The authors concluded that vitamin D supplementation associated with asthma controllers could significantly improve FEV1 in mild to moderate persistent asthma. It takes time to work and the effect tooks months to emerge.
The effects of vitamin D supplementation on airway functions in mild to moderate persistent asthma. Saba Arshi et al. Annals of Allergy, Asthma & Immunology, Volume 113, Issue 4, Pages 404–409, October 2014.
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