People who get fewer than 6 hours of sleep each night are more likely to catch a cold, researchers are saying.
In what is believed to be the first study of its kind, researchers say people are 4 times more likely to come down with the common cold if they get less than 6 hours of shut-eye per night, compared with those who get at least seven or more hours of sleep. [1]
The study included 164 men and women aged 18 to 55 from the Pittsburgh, Pennsylvania area that were recruited between 2007 to 2011. Participants underwent extensive health screenings, questionnaires, and interviews to determine their levels of stress, their general temperament, and their use of alcohol and tobacco. The scientists measured the participants’ normal sleep habits for a week.
Then, the individuals were sequestered in a hotel, where researchers administered nasal drops containing the miserable but very common cold virus.
The volunteers were monitored for a week and the scientists took daily mucus samples to see if they had become infected.
- Scientists found that those who slept less than 6 hours a night the week before the exposure were 4.2 times more likely to catch the cold compared with those who got more than seven hours of sleep.
- Those who slept less than 5 hours a night were 4.5 times more likely to get sick.
- Those who slept just over 6 hours but less than seven weren’t at increased risk.
Aric A. Prather, an assistant professor of psychiatry at the University of California, San Francisco, who is the lead author of the study, explained in the report published online this week in the journal Sleep that the immune system is partly regulated by sleep, and that’s why scientists think a lack of sleep negatively influences immunity.
Previous research found similar results, but in those studies participants reported the number of hours they slept, rather than relying on researchers to actually measure sleep. For this study, scientists used wrist actigraphy, a technology that utilizes a watch-like device with an accelerometer that measures movement and inactivity. The team used this data in combination with participants’ sleep diaries to get a more accurate accounting of sleep.
“This study reinforces the notion that sleep is just as important to your health as diet and exercise,” said Dr. Nathaniel F. Watson, president of the American Academy of Sleep Medicine. “People need to view sleep as a tool to achieve a healthy life, rather than as something that interferes with all their other activities.”
Unfortunately, a lack of sleep is common among Americans. According to a 2013 National Sleep Foundation survey, 1 in 5 adults get less than 5 hours of sleep per work night, on average. The American Academy of Sleep Medicine and the Sleep Research Society said in guidelines released this year that adults should get 7 or more hours of sleep each night.
Less than 7 hours of sleep can lead to weight gain, diabetes, hypertension, heart disease and stroke, depression, ‘significant’ aging of the brain, premature death, as well as “impaired immune function, increased pain, impaired performance, increased errors and greater risk of accidents,” the guidelines state.
On the other hand, sleep can actually help remove toxic waste from the brain. So the bottom line? Get more sleep!
[1] The New York Times