Vitamin D supplements cuts severe risk of asthma attacks by half

Taking oral vitamin D supplements in addition to standard asthma medication can half the risk of asthma attacks, in people with mild to moderate asthma, reveals a recent study.

The findings indicated that there was 50 percent reduction in the risk of people experiencing at least one asthma attack requiring Accident and Emergency Department attendance or hospitalisation.

Asthma deaths arise primarily during episodes of acute worsening of symptoms, known as attacks or 'exacerbations', which are commonly triggered by viral upper respiratory infections.

According to Queen Mary University of London researchers, vitamin D is thought to protect against such attacks by boosting immune responses to respiratory viruses and dampening down harmful airway inflammation.

They analysed 955 participants in seven randomised controlled trials, which tested the use of vitamin D supplements.

They also found a 30 percent reduction in the rate of asthma attacks requiring treatment with steroid tablets or injections.

The results were based on data from adults with mild to moderate asthma: children and adults with severe asthma were relatively under-represented in the dataset.

Lead researcher Adrian Martineau said that results add to the ever growing body of evidence that vitamin D can support immune function as well as bone health.

"On average, three people in the UK die from asthma attacks every day. Vitamin D is safe to take and relatively cost-effective strategy to reduce this problem," Martineau added.

These participants saw a 55 per cent reduction in the rate of asthma exacerbations requiring treatment with steroid tablets or injections - from 0.42 events per person per year to 0.19.

The research appears in the Lancet Respiratory Medicine journal.