Vitamin D May Ease Asthma
Low Vitamin D Levels Associated With Worse Asthma and Lung Function, Study Finds
Jan. 28, 2010 -- Not getting enough vitamin D may make asthma worse,
according to a new study.
Researchers found that low vitamin D levels were associated with worse lung
function compared to higher vitamin D levels in people with asthma.
In addition, the study showed that people with low vitamin D levels didn’t
respond as well to asthma treatments compared to people with higher vitamin D
"Our findings suggest that vitamin D levels influence a number of important
features of asthma, including lung function, bronchospasm, and therapeutic
response to steroids,” researcher E. Rand Sutherland, MD, MPH, chief of the
pulmonary division at National Jewish Health in Denver, says in a news release.
“The next question to answer is whether giving supplemental vitamin D will lead
to clinical improvements in patients with asthma."
Vitamin D is most commonly produced by the skin in response to exposure to
sunlight and is also found in some foods.
Vitamin D Tied to Asthma Severity
In the study, published in American Journal of Respiratory and Critical
Care Medicine, researchers compared vitamin D levels and asthma severity in
54 people with asthma.
The results showed that people with higher vitamin D levels had better lung
function measures than people with lower vitamin D levels. In particular,
people with low vitamin D performed worse on tests of lung function and airway
hyper-responsiveness, two hallmarks of asthma.
Researchers say vitamin D levels were directly related to the participants’
score on the breathing tests: the lower the vitamin D levels, the worse their
For example, airway hyper-responsiveness was nearly twice as bad in people
with vitamin D insufficiency (below the threshold level of 30
nanograms/milliliter) as in those with higher vitamin D levels.
The study also showed that low vitamin D levels were associated with
increased production of a pro-inflammatory protein in the blood, which raises
the possibility that low vitamin D levels could be related to increased
inflammation in people with asthma.