A History of Cow's Milk Allergy Is Associated with Lower Vitamin D Status in Schoolchildren.

Background/aims: Vitamin D insufficiency is common in children. We aimed to evaluate the main determinants of vitamin D status in Finnish school-aged children, including the history of allergic diseases.

Methods: We conducted a cross-sectional study on 171 ten-year-olds where serum 25-hydroxyvitamin D (25[OH]D) levels were measured, and data on food consumption and use of vitamin D supplements were collected. The history of allergic diseases was evaluated with a validated questionnaire.

Results: Vitamin D insufficiency (<50 nmol/L) was observed in 16% of the children. In children with a history of cow's milk allergy, the mean 25(OH)D levels were lower than in children without allergy (60.5 ± 12.6 nmol/L vs. 75.5 ± 22.3 nmol/L, p = 0.004). Lack of vitamin D supplementation, female gender, non-Caucasian ethnicity, and a history of milk allergy were associated with lower vitamin D status.

Conclusion: The vitamin D status in our study sample of Finnish schoolchildren was sufficient, which suggests that health policy strategies - such as the recommendation of vitamin D supplementation and the fortification of food products with vitamin D - have been successful in improving vitamin D status in children. Special concern should be given to children with a history of milk allergy to ensure their vitamin D sufficiency.