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, helping people to live longer. An easy-to-understand summary of the research in this area, refuting these beliefs, has now been published on IQWiG's website www.informedhealthonline.org. "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.

白天越來越短，溫度越來越低，感冒和流感的流行期來臨了。很多人開始服用維C片來預防。但是，研究已經表明，維生素片幾乎不能提供預防功效，不如勤洗手有效。過多服用維生素片反而對人體有害。德國 IQWiG（The German Institute for Quality and Efficiency in Health Care）發表了相關信息和測驗，來幫助人們消除謠言，廓清事實。

讓人期待的傳聞馬上被當真

許多人高估了維C和其它抗氧化劑的好處。多年來，人們相信，服用維C片不但能預防感冒，而且能防癌，從而使人長壽。該領域一份通俗易懂的研究報告否定了維C片的諸多益處，該報告已經發表在 IQWiG 的網站（www.informedhealthonline.org）上。“沒有證據表明抗氧化劑能使人長壽，相反，有些證據表明某些產品可能導致壽命縮短。”Peter Sawicki 教授說，他是該研究所的主任。

“正面”傳聞帶給人們希望，因此能快速傳播，深入人心。Sawichi 教授說：“要人們接受他們深信不疑的事情只是謠傳，非常困難，但是，那些確非事實，除非將來的研究能證明其正確或者我們是錯的。”

簡單的方法能夠預防呼吸道傳染病

鼻涕不止的鼻子和疼痛的喉嚨是病毒感染的信號，能夠幫助判斷是否患上了輕度感冒或者流感。許多人確信維生素C能夠預防呼吸道傳染病。但是，研究表明維C不能預防，服用過多甚至對人體有害。

有很多簡單而有效的方式降低呼吸道感染的風險。包括用合符標準的肥皂和水洗手，以及不要用手接觸臉等等。已經染病的患者可以通過立即丟棄用過的紙巾，避免和他人握手來防止疾病傳播。