Vitamin D benefits for colds and flus scrutinised

Vitamin D supplements won’t stop you from getting a cold or the flu but they may provide some help, Queenslander research has found.

People who buy vitamin D supplements to stave off colds and flus could be wasting their money, new research led by Queenslanders has discovered.

A randomised controlled trial of the supplements, headed by QIMR Berghofer Medical Research Institute, has found they do not protect most people from developing colds, flus and other acute respiratory infections but if you are unwell the supplements could help reduce the severity of the illnesses.

The trial, which is the largest of its kind to study the relationship between vitamin D and respiratory infection to date did show that if you are unwell the supplements may shorten the length of infection slightly and help ease the severity of those illnesses.

The study results have been published in the scientific journal The Lancet Diabetes and Endocrinology.

The researchers analysed self-reported health data from 16,000 Australians aged between 60 and 84, who participated in the QIMR Berghofer-led D-Health Trial.

Lead researcher and head of QIMR Berghofer’s Cancer Aetiology and Prevention group, Professor Rachel Neale, said participants who received vitamin D supplements reported they had cold and flu symptoms for slightly less time than participants who did not take the vitamin. They also had severe symptoms for less time and needed less medication to manage their symptoms.

Professor Neale said the trial results are timely as people around the globe try to understand how best to improve their immunity in the face of the COVID-19 pandemic.

“The D-Health Trial was completed before the COVID-19 pandemic began so does not provide specific answers about this. However, our findings about the reduced length and severity of respiratory tract infection suggests there could be some benefit to the immune system of taking a vitamin D supplement, particularly in people who are deficient.”

Vitamin D testing is on the radar of Queensland GPs as the vitamin is linked to infertility, brittle bones, low immunity and lack of sleep. The intense focus on testing for deficiency prompted the Federal Government back in 2014 to step in and encourage doctors to cut back on the costly tests. There was a reduction but last year showed a significant return of the testing with the cost to the Commonwealth Government hitting $104m.