Abstract
Increasing evidence supports the immunomodulatory effect of vitamin D on allergic diseases. The combined role of prenatal and postnatal vitamin D status in the development of food sensitization (FS) and food allergy remains understudied. Plasma 25-hydroxyvitamin D (25(OH)D) levels of 460 children in the Boston Birth Cohort (BBC) were measured at birth and early childhood, and the subjects were genotyped for rs2243250 (C-590T) in the IL4 gene. We defined FS as specific IgE levels of ≥0.35 kUA/l to any of eight common food allergens; we defined persistently low vitamin D status as cord blood 25(OH)D <11 ng ml and postnatal 25(oh)d><30 ng ml. we observed a moderate correlation between cord blood 25(oh)d at birth and venous blood 25(oh)d measured at 2-3 y (r="0.63)," but a weak correlation at><1 y (r="0.28)." there was no association between low vitamin d status and fs at any single time point alone. however, in combination, persistence of low vitamin d status at birth and in early childhood increased the risk of fs (odds ratio (or)="2.03," 95% confidence interval (ci): 1.02-4.04), particularly among children carrying the c allele of rs2243250 (or="3.23," 95% ci: 1.37-7.60). prenatal and early postnatal vitamin d levels, along with individual genetic susceptibility, should be considered in assessing the role of vitamin d in the development of fs and food allergy.>
