M Majdi - Department of Cellular and Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
F Hosseni - Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.

Introduction: Asthma is a common lung condition that causes breathing difficulties, that Characterized by bronchial hypersensitivity and airway inflammation that leads to coughing, wheezing and breathlessness. Around 235 million people are living with asthma. It is the most common chronic disease among children worldwide which seriously affects children s health and growth. Since the inflammation is an important component in asthma pathogenesis reducing inflammatory potential could also be a promising strategy for lowering asthma risk. Studies have shown that Vitamin D suppresses the proinflammatory cytokines interleukin-17 (IL-17) and IL-13 and promotes the anti-inflammatory cytokines such as IL-10. As this regard, Vitamin D inhibits sensitization in bronchial wall smooth muscle. The aim of this published review was to examine the effect of vitamin D on asthma in children. Methods: A systematic search was conducted from the following databases: PubMed, Google scholar and Scopus by using relevant keywords. Results: some of studies indicate Vitamin D, with anti-inflammatory and immune-modulatory effects, may be effective on the severity and level of symptoms control in childhood asthma. Although the asthmatic children had lower vitamin D levels as compared to non-asthmatic children, but the correlations between vitamin D and asthma and lung functions is different. Conclusion: The association between Vitamin D and asthma and lung function had different results. Randomized controlled trials are required to determine if children with asthma can benefit from Vitamin D supplementation.

Asthma, lung function, Vitamin D, Children, Systematic review