Night owls face the risk of earlier death‚ study concludes


Scientists have long studied whether night owls are saddled with health effects - some research has linked a preference for sleeping late to higher rates of diabetes, heart disease and obesity, among others.

"'Night owls" trying to live in a "morning lark' world may have health consequences for their bodies", study co-author Kristen Knutson, an associate professor of neurology at Northwestern University Feinberg School of Medicine, said in a statement.

"Part of it you don't have any control over", she said, "part of it you might".

There wasn't much difference among people who fell in the middle.

Knutson said that one problem night owls face is living in the morning lark work.

The participants had defined themselves as either "definitely a morning person" (27 percent), "more a morning person than evening person" (35 percent), "more an evening than a morning person" (28 percent), or "definitely an evening person" (9 percent).

Society should wake up to the real difficulties faced by night owls, said the researchers. But even after accounting for these conditions, the study still found that evening people had a slightly higher risk of dying during the study period, compared with morning people. Earlier studies have already found higher rates of metabolic problems and cardiovascular diseases in people who are active at night.

Research based on 50,000 people in the United Kingdom found they had the higher chance of death over the six-and-a-half year period they were being studied.

"It could be that people who are up late have an internal biological clock that doesn't match their external environment", Knutson told the American Association for the Advancement of Science.

They compared the different types, adjusting for a range of factors, including the study participants' age, sleep duration and existing health problems.

Their advice on handling such an issue; Knutson said that: "If you can recognize who these people are, in part, genetically determined and not just a character flaw, jobs and work hours could have more flexibility for owls". "That not only makes it hard to fall asleep; it's also a signal to your clock to start being later again". But overall, the tendency to feel more alert and alive in the morning or evening remains, no matter how much people try to change it. In the study, the researchers say that estimates are that between 21% and 52% of what determines chronotype has genetic roots. "It's strong in that it's a big sample of almost half a million people, but it is mainly Caucasians of Irish or English descent".

That tension between an evening person's preferred routine and the routine of their environment also tends to lead to more irregular schedules, she added.

Being a night owl was associated with psychological stress, eating at the wrong time, lack of exercise, lack of sleep, and drug or alcohol use.