No association between allergy and current 25-hydroxy vitamin D in serum or vitamin D intake.

AIM: Vitamin D may be involved in allergy development, but there is conflicting evidence. We investigated if dietary intake of vitamin D and levels of 25OHD in serum differed between allergic and nonallergic adolescents and if serum 25OHD correlated with dietary intake of vitamin D or season of blood sampling.
METHODS: Serum 25-hydroxy vitamin D (25OHD) levels were analysed in 13-year-old subjects with atopic eczema (n = 55), respiratory allergy (n = 55) or no allergy (n = 55). Intake of fat-containing foods was assessed by food-frequency questionnaires, and total daily vitamin D intake was calculated. Logistic regression was used to adjust for gender, parental allergy and time of blood sampling.
RESULTS: Subjects with atopic eczema or respiratory allergy did not differ from nonallergic controls regarding serum 25OHD levels or calculated vitamin D intake. Subjects sampled in the autumn had significantly higher levels of serum 25OHD than subjects sampled in the winter or spring. Serum 25OHD levels correlated to consumption of vitamin D-fortified lean milk (p = 0.001).
CONCLUSION: The findings suggest no association between allergy and 25OHD levels in serum or vitamin D intake in adolescents. Serum 25OHD levels correlated to intake of vitamin D-fortified lean milk. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.