
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.
References:
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.
http://www.annallergy.org/article/S1081-1206(14)00463-3/abstract
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