Have you ever wondered why colds and other respiratory infections are four times more common during winter than summer? Cold weather is mostly to blame - viruses can survive longer outside the body when temperatures are reduced, surviving on door handles, tissues and other surfaces for at least 24 hours. Inhaling cold air reduces immune responses within the nasal lining. Lack of sunshine lowers your levels of vitamin D, which also impairs immunity and, of course, we spend more time cooped up together indoors so that infections can spread.
Exposure to cold viruses doesn’t mean you have to succumb, however. If your immune system is working at peak performance, you can shrug off the hundred plus viruses that cause the common cold without developing significant symptoms.
