Study: Vitamin D Significantly Helps Prevent Colds, Flu

LONDON — With flu season peaking throughout nearly the entire country, right now may be as good a time as ever to get your local vitamin store. A new major global study finds vitamin D helps shield against respiratory infections such as colds and influenza, especially in those who are deficient in it.

Researchers at the Queen Mary University of London found that Vitamin D has health benefits beyond its effect on muscle and bone, what it is most known for, and could lead the way for new public health policies, such as infusing food with the vitamin.

A new major study finds that vitamin D may be as effective as an injectable flu vaccine against flu-like illnesses.

“The bottom line is that the protective effects of vitamin D supplementation are strongest in those who have the lowest vitamin D levels, and when supplementation is given daily or weekly rather than in more widely spaced doses,” said professor Adrian Martineau from QMUL, a lead researcher in the study, in a university release.

“By demonstrating this new benefit of vitamin D, our study strengthens the case for introducing food fortification to improve vitamin D levels in countries such as the UK where profound vitamin D deficiency is common,” he continued.

The study, which published its results in the British Medical Journal, analyzed data from clinical trials which included nearly 11,000 participants from 14 different countries ages 0 to 95. Researchers noted that the information did return some conflicting results, showing that Vitamin D both helped respiratory infections and had no effect.

“Our analysis of pooled raw data from each of the 10,933 trial participants allowed us to address the thorny question of why vitamin D ‘worked’ in some trials, but not in others,” said Martineau.

For those interested in the science behind the study, researchers noted in the release:

Daily or weekly supplementation halved the risk of acute respiratory infection in people with the lowest baseline vitamin D levels, below 25 nanomoles per litre (nmol/L). However, people with higher baseline vitamin D levels also benefited, although the effect was more modest (10 per cent risk reduction). Overall, the reduction in risk of acute respiratory infection induced by vitamin D was on a par with the protective effect of injectable ‘flu vaccine against ‘flu-like illnesses.

Vitamin D, according to the National Institutes of Health, has been shown to have numerous health benefits, including the potential to reduce the risk of colon, prostate, and breast cancers. Other research has shown it may help in the prevention of diabetes, hypertension, and multiple sclerosis.