Asthmatic s with more severe symptoms tend to have low levels of vitamin D, while those with high levels are able to control their symptoms better. Researchers at King's College London say the connection between levels of the vitamin and severity of symptoms is "quite striking".
In laboratory tests with blood samples, the researchers saw that the vitamin was able to lower levels of interleukin-17, a chemical that helps fight off infection. However, in asthmatics the chemical is in constant over-ride, causing the typical symptoms of inflamed, swollen and narrowed airways.
The researchers plan to carry out clinical trials to establish if the vitamin can ease an asthma attack.
(Source: Journal of Allergy and Clinical Immunology, 2013; published online, May 17, 2013).