Good sleep hygiene is, as we’ve written previously, integral to good physical and mental health. Not getting enough can inhibit how well we function during the day, and increase the risk of illness.

In the past, studies have suggested a link between too much or too little sleep and an increased risk of early mortality. But none have looked at the impact of weekend sleep specifically.

A new study has done exactly this, by analysing weekday and weekend sleep patterns, and examining whether these can have an impact on mortality risk. The study was published in The Journal of Sleep Research, and prompted several media headlines that seemed to suggest that weekend lie-ins can stave off an early death.

In this post, we’ll take a look at the study in more detail.

How was the study carried out?

The observational study used record-linkages to follow the 43,880 subjects for 13 years. Record linkage is a type of data acquisition which involves using multiple sources to retrieve information on the same person.

Participants also provided self-reported data, through questionnaires, on their sleep habits from 1997 until 2010.

The research received financial backing from the Italian Institute Stockholm and AFA Insurance. It was undertaken by the Karolinska Institute and Stockholm University in Sweden, and Texas A&M University in the US.

The results

Compared to the reference group that regularly slept for 6-7 hours per night on both evenings and weekends:

  • adults under 65 who regularly slept for five hours or less throughout the seven day week were found to have an increased risk of death during the 13-year follow up period. This group were 65 percent more likely to have died
  • adults under 65 who during weekends slept for five hours or less had an increased risk of death (52 percent more likely to have died)
  • and people under 65 who slept upwards of eight hours during the week and nine hours on the weekend were 25 percent more likely to have died.

Other sleep patterns, including shorter sleep on weekdays combined with longer sleep at the weekend, did not produce a change in the mortality rate, when compared with the 6-7 hour reference group.

In adults over the age of 65, no link between weekday/weekend sleep and mortality risk was observed.

What do the findings suggest?

The findings serve as confirmation that not getting enough sleep over the long-term can negatively impact on health.

The researchers suggested, because no increased risk was observed in the group having shorter weekday sleep/longer weekend sleep, that [...] long weekend sleep may compensate for short weekday sleep.’

However, the researchers also recognised that their study is only ‘speculative’ and that further research is required to confirm any of the findings.

The fact that the over 65 age group did not produce a difference between weekend and weekday sleep could be because Swedish people tend to retire at the age of 65.

Are we getting enough sleep?

The NHS says that most adults require between six and nine hours of sleep each night. A regular bedtime can help to let your bodyclock know that it needs to wind down and prepare for sleep.

A lack of sufficient sleep can contribute to several health issues such as stress, obesity and diabetes, and exacerbate conditions such as asthma.

If you’re experiencing problems with sleep or are concerned that it may be impacting on your health, speak to your doctor for advice.