Asked by: Sam Robertson, Swindon
Probably. This may be how the ‘common cold’ got its name. The main virus responsible, rhinovirus, is around us all the time. So whether or not you become ill depends on your immune function and, conceivably, this could be affected by temperature. Lots of experiments have been done to find out, with mixed results. In a 2005 experiment, 90 people kept their feet in a bowl of ice and water for 20 minutes: after five days nearly 30 per cent had cold symptoms. Ninety more put their feet in an empty bowl, and less than 10 per cent of them developed colds. Possibly the cold constricts blood vessels in the nose and throat, reducing the effectiveness of the white blood cells that fight infection. It may be that there’s a survival strategy at work. Our immune systems use lots of energy and during bitterly cold conditions it may be wiser to divert all that energy into keeping warm. After all, there’s no point in trying to avoid a virus if you’re about to die of hypothermia.
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