Here's another reason to treat vitamin D deficiency

Taking vitamin D supplements could reduce the risk of deadly lung attacks in some chronic obstructive pulmonary disease (COPD) patients, finds a recent study.

Conducted by researchers at Queen Mary University of London, the study has been published in the journal Thorax.

The findings add to a growing list of health benefits for the 'sunshine vitamin'. While vitamin D is best known for its effects on bone health, previous studies have revealed its role in protecting against colds, flu and asthma attacks, and even helping with weight gain and brain development in malnourished children.

The latest research found that the use of vitamin D supplements led to a 45 per cent reduction in lung attacks among COPD patients who were deficient in vitamin D. No benefit was seen for patients with higher vitamin D levels.

COPD describes a number of lung conditions, including emphysema and chronic bronchitis, where a person's airways become inflamed, making it harder to breathe 1. Almost all COPD deaths are due to lung attacks (termed 'exacerbations') in which symptoms worsen acutely. These are often triggered by viral upper respiratory infections - the type that cause the common cold.

The disease affects more than 170 million people worldwide, and caused an estimated 3.2 million deaths in 2015.

Lead researcher Professor Adrian Martineau said: "New treatments are urgently needed to prevent COPD attacks. Our study shows that giving supplements to vitamin D-deficient COPD patients nearly halves their rate of potentially fatal attacks.

"Vitamin D supplementation is safe, and it costs just a few pence to supplement a person for a year - so this is a potentially highly cost-effective treatment that could be targeted at those who have low vitamin D levels following routine testing.

The analysis found that vitamin D supplements, given by mouth, reduced the rate of moderate/severe COPD exacerbations in patients with low vitamin D levels (less than 25 nmol per litre of blood or 10 nanograms per millilitre).

Doses of vitamin D ranged from 30 micrograms daily to 2500 micrograms monthly. Supplementation did not influence the proportion of participants experiencing serious adverse events, indicating that it was safe.

Giving supplements to patients who did not have such low levels of vitamin D did not reduce their risk of COPD attacks. The researchers therefore highlight that this would need to be a targeted therapy, with doctors first testing vitamin D levels in COPD patients who experience frequent attacks, and then giving vitamin D supplements to those who are deficient.