Those who sleep about six hours a night are four times more likely to catch a cold than those who sleep at least seven hours.
UC San Francisco psychiatrist Aric Prather, along with Carnegie Mallon University psychologist Sheldon Cohen, conducted a study over several years that involved men and women aged 18 to 55 ( only 164 people). Before conducting the experiment, each of them was observed for two months, conducted medical examinations, interviews and questionnaires to take into account factors such as stress level, temperament, alcohol consumption and smoking. For seven days before the experiment, the researchers recorded the duration of sleep of the subjects, and also monitored the quality of sleep using a special sensor.
During the experiment, volunteers were placed in a separate room and drops containing rhinovirus, which causes a cold, were dropped into their noses. They were then observed for a week and nasal mucus samples were taken daily to assess whether a viral infection was developing.
It turned out that those subjects who slept less than six hours a day during the week before the experiment were 4,2 times more likely to get a cold, and those who slept less than five hours were 4,5 times more likely than those who slept more than seven hours.
“The consequences of lack of sleep are not just drowsiness and irritability. Lack of sleep directly affects human health,” says Arik Prater.
The scientists emphasize that compared to other studies in which participants were specifically kept awake, in their experiment, no one limited sleep, so the conditions were much closer to real. These results prove once again that adequate sleep is just as important for a healthy lifestyle as proper nutrition and physical activity. However, convincing people to sleep more is not easy. “In our society, where everyone is constantly busy with business, work at the expense of sleep has become to some extent a cause for pride. Research like this is important to show how important sleep is for health and well-being,” emphasizes Arik Prater.
Подробнее см. А. Prather et al. «Behaviorally Assessed Sleep and Susceptibility to the Common Cold», Sleep, 2015, vol. 38, № 09.