When mucus is moist, it's better able to capture the viruses and pass them to the stomach, where they perish in acid. And the more infected people you are exposed to, the greater your chances of catching a cold. But that doesn't mean you should become a hermit. One safeguard against the common cold is simply to wash your hands frequently and thoroughly. For example, if you don't get enough sleep or if you're under stress, the cold is better able to attack your immune system.
Older people are less resistant to colds and viruses.
Double your fluid intake, because colds thrive in dryness.