Minerals, vitamins, oils and Echinacea were among the top recommendations for supplements to take, while the annual flu jab and other vaccines, “the most proven and effective method of boosting immunity”, were only mentioned by 12% of the websites analysed and in 5% of the commercial websites.
The research, led by Brighton and Sussex Medical School (BSMS), run by the universities of Brighton and Sussex, said: “This means that vaccines ranked at a lowly 27th on the list out of all the ways you can boost your immunity, according to online sources.
“Nearly 80% of the websites analysed did advise people to eat a healthy diet including fruit, which was reassuring, but 36% suggested various supplements.”
Professor Pietro Ghezzi, Chair of Experimental Medicine at BSMS and lead author of the study, said: “We all need to eat a balanced diet to stay healthy, but taking supplements isn’t a proven way of boosting our immunity. For example, if we don’t eat enough vitamin C we can get scurvy, but why do so many people believe that taking additional vitamin C or antioxidants is good for their immune system?
“This study shows how much information exists online is not based on scientific evidence, such as that which is obtained with clinical trials.”
Professor Ghezzi added: “While the study does not explain why healthy people believe that they should take vitamins or antioxidants to boost their immunity and prevent infection, it shows that much of the information common knowledge is built upon is based on commercially-biased sources. More importantly, it is astonishing how most of this information does not mention vaccines.”
The study, titled ‘Boosting the immune system, from science to myth: analysis the infosphere with Google’, is published by Frontiers in Medicine.