New research confirms your grandmother was right: getting enough sleep keeps your immune system in good working order. Those who get less than five hours nightly should be considered sleep deprived people.
Experimental Colds:
The study included 164 healthy young men and women who kept track of their sleep every night for a week using diaries and devices. Then they were deliberately exposed to a standard quantity of cold virus, which was sprayed into their noses. After the exposure the volunteers were quarantined and monitored to see if they started sniffling, sneezing and coughing within five days.
The Results:
Forty-five percent of those who averaged less than five hours of sleep nightly as measured by the wrist devices came down with cold symptoms, compared to just 17 percent of those who slept at least seven hours most nights. The sleep diaries did not correlate closely to whether or not people caught colds, so sleepers’ perceptions of their sleeping or sleeplessness may not be that accurate.
The authors point out that previous research has shown immune system impairment in sleep deprived people. They did not study immune system activity in these volunteers. Nor does anyone know whether interventions to improve sleep such as medication or cognitive behavioral therapy would boost immune defenses against infection.
