Background and aims: Vitamin D deficiency is a common problem of the world that has many complications, especially in adults. Studies suggest a relationship between low levels of vitamin D and allergic diseases. Regarding to the role of vitamin D in the regulation of immune system, Vitamin D deficiency can be one of the effective factors in the development and exacerbation of allergic diseases. Hence, the present study was aimed to examine the relationship between vitamin D levels and the amount of IgE in adults with allergies (type 1) in Tehran.

Methods: In a cross-sectional study, 80 people with allergies (28 males and 52 females) older than 16 years old referred to the Khorshid Allergy and immunology Clinic were evaluated. Vitamin D and total IgE levels were determined by ELISA. Three levels of vitamin D deficiency (less than 20 ng/ml), insufficient (30-20 ng/ml) and sufficient (more 30 than ng/ml) were classified. In order to confirm the presence of specific IgE, skin prick test was used. Finally, the data were analyzed by SPSS software version 20.

Results: The mean level of vitamin D in the all subjects was 21.59 ng/ml that fall into insufficient range (less than 30 ng/ml). Based on the results, the abnormal level of vitamin D was present in 76.25% (65% insufficient and 11.25% deficient) and only 23.75% of them had sufficient vitamin D levels. The results also showed abnormal level of vitamin D in women was more than men (67.21% to 32.78%). In addition, vitamin D deficiency was significantly associated with female group (P=0.01).

Conclusion: Because of the prevalence of vitamin D deficiency, identification of effective factors on vitamin D deficiency and also its impact on the incidence of allergic diseases, it seems necessary to study vitamin D deficiency and how to prevent it.