Confirming what mothers have been telling us for years, a new study has shown that not getting enough sleep can make you more susceptible to colds.
The study, published in the journal Sleep, found that people who slept six hours a night or less were about four times more likely to catch a cold than those who slept more than seven hours. Four times?! That’s insane. There’s no way you’re going to be able to get a good night’s sleep after finding this out. Which means you’re going to get a cold.
The team recruited 164 healthy volunteers and, over a two-month preparation period, established their baseline health levels and sleeping habits. Their quality of sleep was measured using an actigraph unit — sort of like a FitBit that monitors levels of rest and activity.
Isolating the volunteers in a hotel, the researchers infected each of them with a cold virus using nasal drops. Over the next five days, they collected daily mucus samples from each of the participants to see whether the cold virus had taken hold.
While people who didn’t get enough sleep were more prone to getting sick, those who slept six to seven hours weren’t any more or less susceptible. The team monitored the role of other health-related factors in susceptibility, but none of them was as important as sleep.
“Short sleep was more important than any other factor in predicting subjects’ likelihood of catching cold,” said University of California, San Francisco’s Dr. Aric Prather, who led the study, in a press release. “It didn’t matter how old people were, their stress levels, their race, education or income. It didn’t matter if they were a smoker. With all those things taken into account, statistically sleep still carried the day.”