Will you catch a cold if you go out with wet hair? The straight answer: No The facts: As youngsters, we were warned to never step out of the house with wet hair - and especially if it was raining or freezing outside. The reason? The dampness of your head combined with the bone-chilling air could leave you more susceptible to a cold. But the idea that you can fall sick from being outdoors with wet hair is false, says Dr Winnie Mui, a general practitioner at Doctor Laura Bramley & Partners in Central. The real cause of the common cold, which affects the upper respiratory tract, including the sinuses, is exposure to one of more than 200 viruses, the most common of which are called rhinoviruses. The virus attaches itself to, and attacks the lining of the nose and throat, causing inflammation in these areas. Once you have been infected, you become contagious for a couple of days before the actual symptoms begin and remain contagious until all the symptoms disappear. It's not unusual for adults to have between two and four colds a year. Infants and young children are likely to suffer from a cold more often - about six to eight times a year. The symptoms of a cold include nasal stuffiness, a runny nose, sneezing, a cough, body chills, and a dry, scratchy or sore throat. If you've caught one, it's likely that you contracted the virus from an infected person. Mui says the cold virus is generally transmitted through droplets from the infected person's mouth or nose when he coughs or sneezes around you. You can also catch a cold if you touch something that has been contaminated with the virus, such as a door handle, a computer keyboard, a counter-top, or a utensil, and then touch your nose or mouth after. When your immune system has been compromised as a result of stress or fatigue, or if you suffer from certain allergies that affect your nose or throat, you may be more vulnerable to catching a cold. To minimise your chances of falling sick, avoid touching your eyes, nose and mouth. If you have to rub your eyes, be sure to wash your hands thoroughly before an after. It's also wise not to touch public surfaces, as the cold virus can survive on non-porous surfaces for a few hours. Do also practise good hygiene habit. These include washing your hands after using the bathroom, keeping household surfaces clean, and throwing away tissues right after using them. Maintaining a healthy lifestyle and getting sufficient sleep can strengthen your immune system, and help your body fend off the cold virus before it infects you.