Polymorphisms associated with low vitamin D-binding protein levels weakened the association between low serum 25-hydroxyvitamin D3 levels and food allergy, according to study results.
This may increase the biological plausibility of vitamin D insufficiency in the development of food allergy, according to researchers.
Jennifer J. Koplin, PhD, a postdoctoral research fellow with the Murdoch Children’s Research Institute and the University of Melbourne School of Population and Global Health, and colleagues assessed data from a population-based cohort study to determine whether polymorphisms that lower the vitamin D-binding protein (DBP) could make up for adverse effects of low serum vitamin D on food allergy risk.
The analysis included 607 infants — 338 with and 269 without food allergies — aged 1 year. The analysis also included 105 infants — 55 with persistent egg allergy and 50 with resolved egg allergy — aged 2 years.
Low serum 25-hydroxyvitamin D3 levels (25[OH]D3) (less than or equal to 50 nM/L) in infants aged 1 year increased the risk for food allergy, especially in infants with the GG genotype (OR = 6; 95% CI, 0.9-38.9).
However, this did not appear to be the case in infants with GT/TT genotypes (OR = 0.7; 95% CI, 0.2-2).
Persistent vitamin D insufficiency increased the risk for persistent food allergy (OR = 12.6; 95% CI, 1.5-106.6).
The results have future implications for the prevention and treatment of food allergy, according to the researchers.
“Reference ranges to define low levels of 25[OH]D3 with a detrimental biological effect may need to take into account differences in the DPB level, including racial variation, and treatment dosages might also need tailoring,” the researchers wrote. “Further studies should determine whether correction of vitamin D insufficiency could aid in the development of tolerance including during immunotherapy to foods.” – by Ryan McDonald
Disclosure: Koplin reports support from the National Health and Medical Research Council. Please see the full study for a list of all other researchers’ relevant financial disclosures.