It turns out sleeping in at the weekend could counteract the harm caused by lack of sleep during the week

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• People with a night owl chronotype can struggle with a fixed 9-5 routine.
• Failing to get to sleep can mean you don't get a consistent eight hours a night.
• This is bad news because a lack of sleep has been associated with an increased risk of early death.
• But according to new research, you might be able to reduce your risk by catching up with sleep at the weekend.
• However, the consensus in the sleep science community remains that consistency is key, and there is no substitute for a regular bedtime when it comes to your health.

As a night owl, I know what it's like to struggle with the strict schedules society has set for us. Getting to bed to ensure eight hours of sleep is a daily battle, but it's nothing compared to getting up in the morning to make it to work on time.

Throughout the week it can feel like my body hasn't rested enough because I often fail to fall asleep until very late. This means I take the opportunity at weekends to "catch up" on my shut-eye, so I rarely set an alarm, and tend to wake up when my body wants to.

Sleep scientists have long been critical of my method. Sleep scientist Matthew Walker said last year: "Sleep is not like the bank. You can't accumulate a debt and pay it off at a later point in time."

But according to a new study, published in the Journal of Sleep Research, the impact of insufficient sleep over the week could actually be countered by a later lie-in at the weekend.

Sleep researchers from the Stress Research Institute at Stockholm University looked at data from more than 43,000 adults collected in Sweden in 1997. Then, they found out what happened to participants 13 years later by looking at the national death register.

Results showed that adults under age 65 who only got five hours of sleep or fewer a night, seven days a week, had a higher risk of death than those who consistently got six or seven. But those who made up for it at the weekend by sleeping in had no raised mortality risk compared to the steady sleepers.

"The results imply that short (weekday) sleep is not a risk factor for mortality if it is combined with a medium or long weekend sleep," wrote the authors, led by Torbjörn Åkerstedt. "This suggests that short weekday sleep may be compensated for during the weekend, and that this has implications for mortality."

This study follows on from previous research published in 2017, that showed how people who slept less than five hours a night, or more than 8 hours a night, had much higher rates of mortality than those who slept more.

Overall, Åkerstedt suggested it was the average amount of sleep somebody got that seemed to make a difference, and the new study adds to the growing body of research that highlights this.

However, in the sleep science community, the overarching advice is that consistency is key, and there is no substitute for having a regular sleep pattern.

In a previous interview for Business Insider about body clocks, research fellow at Birmingham University Elise Facer-Childs said the more regular your sleep the better. Otherwise you can experience something called "social jetlag," which is the misalignment between social and biological time. (Essentially, our bodies have clocks - or circadian rhythms - and if we mess with them, it can cause problems.)

"I would say that it is all about getting the right balance," Facer-Childs wrote recently in an email. "Yes, if you are extremely sleep deprived during the week then continuing that over the weekend isn't ideal and maybe you should think about getting a few more hours."

She added that the most important thing is the timing of sleep. For example, if you get up at 6 o'clock for work during the week, and then at the weekend you sleep in until 10, that's a four-hour time difference. So for your body, it's like you're flying to Dubai every weekend, then flying back on Sunday - so you're basically jetlagged.

"If you're sleep deprived it is probably better to try and fall asleep earlier than get up later... although our social commitments at the weekend tend to prevent us from doing this," she said.

Not getting enough sleep has been linked to an increased risk of obesity and heart disease, as well as brain diseases like Alzheimer's. There's also evidence sleep deprivation can mean a lower sex drive, reduced fertility, and generally less mental well-being.

So forget "sleep when you're dead." It might be more "don't sleep, and you will be dead."