Good night's sleep may prevent a cold

Dr. Charles Czeisler is a known professor of sleep medicine and chief of sleep medicine at Brigham and Women's Hospital. He said in an interview recently that sleep has major effects on the brain and the health of the body. (Pat Greenhouse/ Globe Staff)

People who sleep averaged less than seven hours per night were about three times more likely to develop cold symptoms than study volunteers who got eight or more hours of sleep, Pittsburgh researchers reported in the Archives of Internal Medicine.

"These results really fit in very well with what has been becoming increasingly clear, which is that sleep has major effects not only on the brain in terms of alertness and performance, but also on the health of the body."

Wound healing has been shown to be affected by sleep. 

A study conducted by Gumustekin et 2004 shows sleep deprivation hindering the healing of burns on rats.

It has also been shown that sleep deprivation affects the immune system and metabolism. In a study by Zager et al. in 2007, rats were deprived of sleep for 24 hours. When compared with a control group, the sleep-deprived rats' blood tests indicated a 20% decrease in white blood cell count, a significant change in the immune system

A biological mechanism that would explain the link between sleep and cold symptoms is not yet known, Cohen said, but getting a good night sleep can help the immune system mount a more robust defense against disease. Previous research suggests it might involve the release of inflammatory chemicals, which cause some of the symptoms of colds. Inflammation is implicated in not just infectious diseases but also in illnesses from autoimmune disorders to heart disease.

"It does have potential implications for a lot of inflammatory diseases," Cohen said about the sleep and colds study.