Once ill, the body starts to dehydrate, says Dr. David Rakel, director of the University of Wisconsin Integrative Medicine Program. Drink often – enough that you're urinating every three to four hours. Hot liquids help hydrate and also give you steam, soothing mucous membranes that are irritated. This is why hot tea, chicken soup, hot showers, and a hot toddy all seem to cure what ails you (in this sense, they do). Over-the-counter medicine with pseudoephedrine and antihistamines can mask the symptoms of a cold but won't shorten its length.
The best thing you can do is keep to a fairly regular routine. "You want to spend time sleeping, but you also want to spend time moving around," says Agus. This helps the lymphatic system circulate immune cells in the body where they're needed. To this end, a handful of studies show that moderate exercise won't make a cold worse, but they are unclear about whether it shortens the duration. Studies have shown that moderate exercise usually makes sick people feel better.