US adults who sleep no more than five hours per night or who have a diagnosed sleep disorder are more likely to have suffered a recent cold than those who sleep more, according to a new study.
"In many countries, particularly western countries, sleep takes a back seat to productivity, which may make some sense in the short term but certainly not the longer term," said coauthor Aric A. Prather of the Center for Health and Community at the University of California, San Francisco. "Sleep happens with whatever time is left after all of the other 'necessary' tasks are attended to."
Getting too little sleep can have a direct impact on cardiovascular, endocrine and immune functioning that may increase disease risk over time, Prather told Reuters Health by email.
In addition, "poor sleep may lead to health behaviours that also raise one's risk for poor heath," he said. "Short sleepers are less likely to exercise and more likely to engage in less than ideal nutrition that, again over time, can affect health."
The researchers used responses from more than 22,000 adults in the National Health and Nutrition Examination Surveys between 2005 and 2012. The participants reported their typical weekday hours of sleep, history of diagnosed sleep disorders and whether they had ever told a doctor about having trouble sleeping.
They also answered questions about having a head or chest cold, the flu, pneumonia, or an ear infection over the previous 30 days.
Almost 14 percent of people said they slept no more than five hours per night, 23 percent slept for six hours, 56 percent slept for seven to eight hours, and 7 percent said they slept for nine or more hours per night.
One quarter had told a doctor about trouble sleeping and 7 percent had been diagnosed with a sleep disorder.