Achoo! Improve your chances of keeping a cold at bay by sleeping long and well at night, researchers say.
Credit: Jason Rogers
WASHINGTON: People who get less than seven hours of sleep at night have an increased risk of catching a cold, researches say.
"Sleep quality is thought to be an important predictor of immunity and, in turn, susceptibility to the common cold," said U.S. researchers, from the Carnegie Mellon University in Pittsburgh, Pennsylvania, writing in the journal Archives of Internal Medicine.
They found that, compared to people who sleep eight hours or more, those who get fewer than seven hours of shut-eye are three times more likely to fall ill.
Sleep long
To make the discovery, the researchers studied 153 people in good health, documenting their sleep habits for two weeks before administering nasal drops that contained the cold-causing rhinovirus.
"Participants were interviewed daily over a two-week period, reporting how many hours they slept per night, what percentage of their time in bed was spent asleep (sleep efficiency) and whether they felt rested," they wrote.
"The less an individual slept, the more likely he or she was to develop a cold."
Sleep well
The quality of sleep obtained was also found to influence the likelihood of catching the sneezes.
"Participants who spent less than 92 per cent of their time in bed asleep were five and a half times more likely to become ill than those whose efficiency was 98 per cent or more," wrote the researchers, though simply feeling 'rested' "was not associated with colds".
Defence disruption
The study authors believe a possible explanation for the link between sleep and cold susceptibility is "that sleep disturbance influences the regulation of [the immune system's] pro-inflammatory cytokines, histamines and other symptom mediators that are released in response to infection."
Indeed, previous research has linked sleep deprivation to reduced immune function, but until now there has been limited evidence that lack of sleep increased the risk of catching the common cold.
