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