HEALTH NEWS

Study Title:

Low Vitamin D Linked to Allergies in Children

Study Abstract

Background
Previous research supports a possible link between low vitamin D levels and atopic disease. However, the association between low vitamin D levels and total and allergen-specific IgE levels has not been studied.

Objective
We sought to test the association between serum 25-hydroxyvitamin D (25[OH]D) deficiency (<15 ng/mL) and insufficiency (15-29 ng/mL) and allergic sensitization measured by serum IgE levels in a US nationally representative sample of 3136 children and adolescents and 3454 adults in the National Health and Nutrition Examination Survey 2005-2006.

Methods
The association of 25(OH)D deficiency with 17 different allergens was assessed after adjustment for potential confounders, including age; sex; race/ethnicity; obesity, low socioeconomic status; frequency of milk intake; daily hours spent watching television, playing videogames, or using a computer; serum cotinine levels; and vitamin D supplement use.

Results
In children and adolescents allergic sensitization to 11 of 17 allergens was more common in those with 25(OH)D deficiency. Compared with sufficient vitamin D levels of greater than 30 ng/mL, after multivariate adjustment, 25(OH)D levels of less than 15 ng/mL were associated with peanut (odds ratio [OR], 2.39; 95% CI, 1.29-4.45), ragweed (OR, 1.83; 95% CI, 1.20-2.80), and oak (OR, 4.75; 95% CI, 1.53-4.94) allergies (P < .01 for all). Eight other allergens were associated with 25(OH)D deficiency, with P values of less than .05 but greater than .01. There were no consistent associations seen between 25(OH)D levels and allergic sensitization in adults.

Conclusion
Vitamin D deficiency is associated with higher levels of IgE sensitization in children and adolescents. Further research is needed to confirm these findings.

From press release:

A study of more than 3,000 children shows that low vitamin D levels are associated with increased likelihood that children will develop allergies, according to a paper published in the February 17 online edition of the Journal of Allergy and Clinical Immunology. Researchers from Albert Einstein College of Medicine of Yeshiva University headed the study.

Researchers looked at the serum vitamin D levels in blood collected in 2005-2006 from a nationally representative sample of more than 3,100 children and adolescents and 3,400 adults. The samples are derived from the National Health and Nutrition Examination Survey (NHANES), a program of studies designed to assess the health and nutritional status of adults and children in the United States. The survey is unique in that it combines interviews, physical examinations and laboratory studies. One of the blood tests assessed was sensitivity to 17 different allergens by measuring levels of Immunoglobulin E (IgE), a protein made when the immune system responds to allergens.

When the resulting data was analyzed by Einstein researchers, no association between vitamin D levels and allergies was observed in adults. But for children and adolescents, low vitamin D levels correlated with sensitivity to 11 of the 17 allergens tested, including both environmental allergens (e.g., ragweed, oak, dog, cockroach) and food allergens (e.g., peanuts). For example, children who had vitamin D deficiency (defined as less than 15 nanograms of vitamin D per milliliter of blood), were 2.4 times as likely to have a peanut allergy than were children with sufficient levels of vitamin D (more than 30 nanograms of vitamin D per milliliter of blood).

The research shows only an association and does not prove that vitamin D deficiency causes allergies in children, cautioned Michal Melamed, M.D., M.H.S., assistant professor of medicine and of epidemiology & population health at Einstein and senior author of the study. Nevertheless, she said, children should certainly consume adequate amounts of the vitamin. "The latest dietary recommendations calling for children to take in 600 IU of vitamin D daily should keep them from becoming vitamin-D deficient," she said.

Study Information

Shimi Sharief, Sunit Jariwala, Juhi Kumar, Paul Muntner, Michal L. Melamed
Vitamin D levels and food and environmental allergies in the United States: Results from the National Health and Nutrition Examination Survey 2005-2006.
Journal of Allergy and Clinical Immunology,
2011 May
Albert Einstein College of Medicine of Yeshiva University.