Amount of Sleep Needed | Sleep Health Blog

Ditch Your Alarm Clock on the Weekends

Amount of Sleep Needed | Sleep Health Blog

We’ve all heard the perils of sleeping late on our days off. It can mess up your circadian rhythms when you get out of your typical sleep routine. Sleeping in is pointless because you can’t bank slumber, so you’ll still be just as tired all week long. Too much sleep may even be associated with chronic conditions such as heart disease and diabetes. But if you love getting the chance to snooze for an extra few hours now and then on a Saturday, you’ll be thrilled to find out that new research suggests it might potentially increase your longevity.

The study, which was conducted at the Karolinska Institute in Stockholm, Sweden, found that getting more sleep on the weekends may counter a lack of sleep during the week…enough to help you live a longer life.1 Akerstedt, Torbjorn; et al. “Sleep duration and mortality — Does weekend sleep matter?” Journal of Sleep Research. 22 May 2018. Accessed 6 June 2018. http://onlinelibrary.wiley.com/doi/pdf/10.1111/jsr.12712. The results were based on an analysis of the sleep habits of 38,015 men and women living throughout Sweden. They answered a detailed survey filled with questions on various aspects of their lifestyles and medical history and were tracked for a 13-year period.

All the subjects were divided into groups determined by their typical sleep habits. These consisted of short sleepers who usually snoozed for less than five hours nightly, a control group who generally slept for seven hours on average, and long sleepers who typically slumbered for more than nine hours each night. The short sleepers had a 65 percent higher mortality rate than their counterparts in the six- to seven-hour group. But those who slept eight hours or more surprisingly had a 25 percent greater risk of death than the control group.

The volunteers were also placed in younger-than-65 and 65-and-older categories, enabling the investigators to determine the effects of sleep on lifespan by comparing similar age groups. Among those under the age of 65, sleeping for an average of five hours or less nightly on weekends was associated with a 52 percent higher risk of death versus their peers who typically slept a minimum of seven hours on the weekends.

Another important finding for the under 65s was that fewer hours of sleep on both weekday and weekend nights raised the chances of early mortality, as did sleeping in excess of eight hours on both weekends and weekdays. However, when those generally sleeping fewer hours during the week slept longer on the weekends, their death rate was very similar to those who logged an average of seven hours of sleep every night of the week, suggesting strongly that catching up on zzz’s on the weekend could mitigate any existing risk. Interestingly, no such connections between the length of slumber and mortality risk were seen in the participants 65 and older.

Some of the findings correlate to those of earlier research, which has shown that health risks rise in those who get their sleep at either end of the spectrum, whether too little sleep each night or too much. The sweet spot often seems to be somewhere in the seven- to eight-hour range per night.

Where this study diverges from some previous findings is in the benefit of catching up on sleep over the weekends, which has gotten mixed reviews in earlier investigations. A 2010 study at Brigham and Women’s Hospital in Boston, Massachusetts showed that we do not benefit from getting extra sleep after sleep loss as reaction time and performance remain impaired.2 Cohen, Daniel A.; et al. “Uncovering Residual Effects of Chronic Sleep Loss on Human Performance.” Science Translational Medicine. 13 January 2010. Accessed 7 June 2018. http://stm.sciencemag.org/content/2/14/14ra3.full. However, a 2013 study at the George Institute for Global Health in Sydney, Australia found that a few more hours of weekend sleep can lower the risk of car crashes in younger drivers.

Ideally, we should do everything we can to achieve seven hours of sleep all seven nights of the week. Think about what might be keeping you up late most nights—watching television, checking social media on your laptop, playing games on your phone? It’s essential to wean yourself away from screen time, especially in the evening when it can affect the quality of your sleep as well. Instead, try reading, listening to soft music, or a warm bath to help you get relaxed and ready for bed. And in those instances, when you just get shortchanged in the weekday sleep department, get back on track with seven to eight hours that weekend.

References

References
1 Akerstedt, Torbjorn; et al. “Sleep duration and mortality — Does weekend sleep matter?” Journal of Sleep Research. 22 May 2018. Accessed 6 June 2018. http://onlinelibrary.wiley.com/doi/pdf/10.1111/jsr.12712.
2 Cohen, Daniel A.; et al. “Uncovering Residual Effects of Chronic Sleep Loss on Human Performance.” Science Translational Medicine. 13 January 2010. Accessed 7 June 2018. http://stm.sciencemag.org/content/2/14/14ra3.full.