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Nocturnal 'night owls' risk early death, study finds

People who stay up late and struggle in the mornings are more likely to die early, a new study has found.

Tracking 500,000 Britons over six years, researchers found night owls had a 10% greater risk of premature death than those who go to bed early and spring out of bed in the mornings.

The risk was the same even when common problems night owls have, like metabolic dysfunction and heart disease, were factored in.

The scientists behind the work are calling for employers to better adapt work schedules to fit their employees' sleep patterns.

Dr Kristen Knutson, a member of the team from Northwestern University in Chicago, said: "Night owls trying to live in a morning lark world may have health consequences for their bodies.

"They shouldn't be forced to get up for an 8am shift. Make work shifts match people's chronotypes. Some people may be better suited to night shifts."

Early risers are better able to adjust their body clocks to the light and dark rhythms of the sun, the researchers found, but night owls' body clocks might not match their external environment.

British co-author Professor Malcolm von Schantz, from the University of Surrey, said: "This is a public health issue that can no longer be ignored.

"We should discuss allowing evening types to start and finish work later, where practical. And we need more research about how we can help evening types cope with the higher effort of keeping their body clock in synchrony with sun time."

The study, which was published in Chronobiology International, found night owls have higher rates of diabetes, mental disorders and neurological conditions.

It's also associated with psychological stress, eating at the wrong time, lack of sleep and exercise and drug or alcohol use.

The study did not look for cause and effect, but for correlation with the researchers developing their own theories as to why it causes early deaths.

Genetics and a person's environment play a largely equal role in whether someone is a lark or an owl, but owls can become morning people by exposing themselves to light early on in the day.

They should also try to avoid light at night, be disciplined with bed times, and tick off to-do lists early in the day, rather than leaving tasks late into the evening.

Dr Knutson added: "You're not doomed. Part of it you don't have any control over, and part of it you might."

The data was taken from UK Biobank, a storehouse of 500,000 people aged between 40 and 69. Researchers sorted each person into four groups - definite morning, definite evening, moderate morning, and moderate evening, before comparing.