Research: Vitamin D Can Not Prevent Flu


Vitamin D does not prevent fluDietary supplements such as vitamins are often used as a way to increase body resistance against influenza virus. Vitamin D is known for keeping the immune system to function better, so that it is much taken to avoid colds. A research broke the common assumption.

Professor and head of pathology at the University of Otago in Christchurch New Zealand, Dr David Murdoch explained, “In adults, vitamin D does not prevent or reduce colds.”

According to Healthday, Murdoch added that there are no evidence for the claim that the nutritional supplement is able to prevent colds. “Currently there are no supplements that are proven to prevent flu,” he said. Several previous studies showed those who had higher levels of vitamin D more rarely have colds or upper respiratory infections.

The study recruited 300 adults in Christchurch. Half of respondents took vitamin D tablets for two months taking 200 thousand IU and 100 thousand IU for the remaining 18 months of the study. The other half took placebo.

Results from the study published in the Journal of the American Medical Association, October 3rd, 2012 found no significant difference between the two groups in terms of the number of flu. The group that consumed vitamin D experienced flu 3.7 times while those consuming placebo had flu 3.8 times for 20 months of the study.

While the number of working days lost due to upper respiratory tract infections are similar between the two groups, which is 12 working days.

“Both groups have the same number of colds, so we can conclude that vitamin D has no effect in preventing colds in this group. This is possible because the number of respondents is limited or too short observation time,” said Murdoch.

In a previous research, it was known that Vitamin D improves fetal brain health.