People who stay up late and struggle to get out of bed in the morning - the “night owls” among us - appear to have a higher risk of early death than “larks” who have a natural preference for an early night.

A study of over 433,000 people by the University of Surrey and Northwestern University, Chicago, found night owls have a 10% higher risk of dying early.

The report suggests that people who are up late often have an internal biological clock that doesn’t match their external environment.

The researchers identified a series of “unhealthy behaviours” associated with people who stay up late.

Kristen Knutson of Northwestern University Feinberg School of Medicine, who co-authored the study, says “It could be psychological stress, eating at the wrong time for their body, not exercising enough, not sleeping enough, being awake at night by yourself, maybe drug or alcohol use.”

Should employers let workers have lie-ins?
Image: REUTERS/Enrique Castro-Mendivil

The study also reveals people who stay up late have higher rates of diabetes as well as psychological and neurological disorders.

Malcolm von Schantz of the University of Surrey, who also worked on the study, says the higher risk of early death in night owls 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”.

Help is at hand

According to the study's authors, genetics and environment play approximately equal roles in whether we are a morning or a night person. Fortunately for owls, it is possible to shift sleep patterns.

“You’re not doomed,” says Knutson, adding that one way to shift behaviour is to make sure you are exposed to light early in the morning but not late at night.

Night owls are also advised to keep a regular bedtime, be regimented about adopting healthy lifestyle behaviours and recognize how important the timing of when you sleep is.

“If we can recognize these chronotypes are, in part, genetically determined and not just a character flaw, jobs and work hours could have more flexibility for owls,” Knutson says “They shouldn’t be forced to get up for an 8am shift.”

We’re not getting enough sleep

Regardless of a person’s natural inclination, most of us are not getting enough sleep.

Analysis of data provided by wearable technology company Fitbit, whose wristbands can track movement, reveals women in the United States average six hours and 50 minutes per night, while men get six hours and 26 minutes.

The amount of time US men and women spend asleep
Image: Yahoo Finance/Fitbit

According to the Centers for Disease Control, the average adult should sleep at least seven hours a night.

Disruptive sleep patterns increase health risks

Working nights is also detrimental to health and interferes with regular sleep patterns. About 15 million Americans work night shifts.

There’s a dark side to working nights
Image: REUTERS/Ueslei Marcelino

Following a study by the Institution of Occupational Safety and Health into the effects of shift work on health, the organization compiled an extensive list of tips for employers and employees.

For example, night shift workers are advised to restrict their energy intake between midnight and 6am, instead eating at the beginning and end of a shift. They are also urged to establish a sleep schedule to facilitate sleeping during the day.

More generally, employees are advised to avoid caffeine, alcohol and large meals before going to sleep.