(NaturalNews) Low vitamin D levels may make asthmatic children significantly more likely to suffer from severe attacks, according to a study conducted by researchers from Harvard Medical School and published in the Journal of Allergy & Clinical Immunology.
The researchers took blood samples from 1,024 children with mild-to-moderate asthma who were enrolled in a study of two inhaled asthma drugs, budesonide and nedocromil. The children were then followed for four years.
For the purposes of the study, vitamin D insufficiency was defined as a blood level less than or equal to 30 nanograms per milliliter. Although it currently takes levels lower than 11 nanograms per milliliter to be classified as a deficiency, doctors increasingly believe that levels of 30 nanograms per milliliter or higher are required for optimal health.
The researchers found that children with vitamin D insufficiency were significantly more likely to suffer from severe asthma attacks than children with higher levels of the vitamin. During the course of the study, 38 percent of vitamin D-insufficient children had to be hospitalized at least once due to an asthma attack, compared with only 32 percent of vitamin-sufficient children.
Vitamin D did not appear to protect children from moderate asthma symptoms; in fact, lower vitamin levels appeared to be correlated with a slightly lower risk of moderate symptoms. The researchers were unable to explain this effect.
Scientists have long known that vitamin D plays a crucial role in the development and maintenance of healthy teeth and bones. More recently, they have discovered that the vitamin plays a vital role in regulating the immune system, and that low levels may increase the risk of allergies, infection, autoimmune diseases, cancer, and heart disease.
The researchers in the current study suggested that the vitamin may help regulate the body's inflammatory response, perhaps even by enhancing the potency of anti-inflammatory hormones. They found that vitamin D appeared to be more protective among participants who were taking budesonide, a synthetic anti-inflammatory hormone.