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Vitamin D may help to fight against flu

By Alisdair Stirling

Vitamin D may protect against influenza and other viral respiratory infections say US researchers.

They studied 195 healthy adults aged 20–88 years, during last year's autumn and winter flu season and measured 25(OH)D levels as a marker for vitamin D each month.

During this period 84 participants suffered 103 acute viral infections.

Just over 83% of the 18 participants who maintained a vitamin D concentration of 38 ng/ml or higher experienced no respiratory tract infections.

Those with a vitamin D concentration above this level were 2.7 times less likely to experience a viral infection of the respiratory tract than those with a vitamin D level below it.

Study leader Dr James Sabetta, an infectious disease specialist at Yale School of Medicine in Connecticut concluded: ‘The data in this study suggest that supplementing with vitamin D to raise the concentrations in the general population to above 38 ng/ml could result in a significant health benefit by reducing the burden of illness from viral infections, at a minimum from viral infections of the respiratory tract in healthy adults.'

PloS one, online June 24