Late nights raise risk of death, says study

Bad news, night owls: Evening types have a 10 percent higher risk of dying than those up and at ’em in the morning, according to a new study from Northwestern Medicine and the United Kingdom’s University of Surrey.

“This is the first study, to our knowledge, that was able to look at mortality risk,” said Kristen Knutson, an associate professor of neurology and sleep researcher at Northwestern.

Night owls have a harder time switching to daylight saving time and are more likely to suffer from diabetes and psychological and neurological disorders, she said.

Researchers surveyed 433,268 participants, ages 38 to 73, in the United Kingdom, asking whether they considered themselves a “definite morning type,” “moderate morning type,” “moderate evening type” or “definite evening type.” Then researchers tracked deaths within the sample.

The study, published April 12 in the Chronobiology International journal, found that the 50,000 peo- ple who identified as definite night owls were more likely to die in the six years researchers followed them.

Knutson and co-author Malcolm von Schantz, a University of Surrey professor who also researches sleep and circadian rhythms, note the increased likelihood of death could be the result of many factors, including behav- iors that can potentially accompany late nights — eating at irregular times, not exercising or sleeping enough, or using drugs and alcohol.