People who sleep less than seven hours a night are three times as likely to catch a cold.
A new study supports the theory that sleep is important to immune function. Volunteers who spent less time in bed were much more likely to catch a cold when viruses were dripped into their noses. People who slept longer and more soundly resisted infection better.
Researchers tested more than 150 healthy volunteers, locking them in a hotel for five days after infecting them with a cold virus. The men and women who reported fewer than seven hours of sleep, on average, were 2.94 times more likely to develop sneezing, sore throat and other cold symptoms. And the volunteers who spent less than 92 percent of their time in bed asleep were 5 and a half times more likely to become ill than better sleepers.