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Vitamin D status in Irish children and adolescents: value of fortification and supplementation
Aoife Carroll1, Chike Onwuneme2, Malachi J McKenna3
1Children's University Hospital, Dublin, Ireland University College Dublin, Dublin, Ireland aoifecar@gmail.com.
Background:
Vitamin D has important skeletal and extraskeletal roles but those living at northerly latitudes are at risk of suboptimal levels because of reduced sunlight exposure.
Aim:
To describe the vitamin D status of Irish children and identify factors predictive of vitamin D status.
Methods:
A prospective cross sectional study was undertaken over a 12 month period. Two hundred and fifty two healthy children attending for minor medical or surgical procedures were recruited. All had 25-hydroxyvitamin D (25OHD), parathyroid hormone and bone profiles measured.
Results:
The mean (standard deviation) for 25OHD was 51(25) nmol/L (20.4 (10) ng/mL). Forty-five percent had levels >50 nmol/L (20 ng/mL). The following variables were significantly associated with 25OHD levels >50 nmol/L (20 ng/mL): sample drawn in April-September, use of vitamin D supplements, consumption of formula milk, and non-African ethnicity.
Conclusion:
More than half of the children in this study had 25OHD levels less than 50 nmol/L (20 ng/mL). Vitamin D status was significantly improved by augmented oral vitamin D intake.
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