The days are getting shorter, temperatures are dropping, and the cold and flu season is beginning. Many people have started taking vitamin C tablets as a precautionary measure. But research has shown that vitamin supplements do not provide nearly as much protection as other measures, like frequently washing your hands – and that high doses can even be harmful.

The German Institute for Quality and Efficiency in Health Care (IQWiG) has published information and a quiz on the subject of prevention, helping to separate widespread myths from facts.

Promising news is quickly assumed to be true

Many people overestimate the benefits of vitamin C and other antioxidants. For years it was believed that taking vitamin C supplements not only provided protection against colds, but also against cancer, thereby helping people to live longer. A summary of the research in this area, refuting these beliefs, has now been published on IQWiG's website.

"Not only is there no proof that some antioxidants prolong life, but there is some evidence that certain products may even lead to earlier death", says Professor Peter Sawicki, the institute's director.

"Positive" news gives people hope, which can quickly spread, become deeply held beliefs. Professor Sawicki: "It can be very difficult to accept that these beliefs are myths, but they are not true if further research does not confirm them or the research points to the opposite conclusion."

Simple strategies can prevent respiratory infections

Whether it is caused by a mild cold or the flu, a runny nose and sore throat are signs of a viral infection. Many people are absolutely convinced that vitamin C provides protection against respiratory infections. Yet research has shown that vitamin C does not prevent infection, and that high doses can even be harmful.

There are many simple but effective ways to lower the risk of respiratory infections. These include frequently washing your hands with normal soap and water, and not touching your face with your hands. People who already have a respiratory infection can stop it from spreading by throwing away tissues immediately after using them and not shaking hands with other people.

For more information on the Institute for Quality and Efficiency in Health Care, visit www.iqwig.de.