Sleeping is a basic human need, like eating, drinking, and breathing. Like these other needs, sleeping is a vital part of the foundation for good health and well-being throughout your lifetime. Yet many people – perhaps even yourself find it difficult to sleep as much as you would like to and forlornly hope that a longer lie in may let you catch up! Did you know that the average Briton gets just six hours and 19 minutes sleep a night, yet back in the 1940s they would average almost 8 hours. In the blink of an eye, in evolutionary terms, humans have radically altered a fundamental biological necessity – with repercussions we are still only beginning to understand.
A new line of research for example suggests poor sleep may increase the risk of Alzheimer’s, as even a single night of sleep deprivation boosts brain levels of the proteins that form toxic clumps found in the brains of people diagnosed with Alzheimer’s. All-nighters push anxiety to clinical levels, and even modest sleep reductions are linked to increased feelings of social isolation and loneliness.
You will already know that metabolic dysfunction including weight gain and insulin resistance have been found to be causally related to disrupted sleep – surely if you catch up on those missing hours in the week or at the weekend then all will be ok?
Let’s first do a quick recap on what sleep deprivation is – it’s a condition that occurs if you don’t get enough sleep (seems straight forward?). Sleep deficiency is a broader concept. It occurs if you have one or more of the following:
- You don’t get enough sleep (sleep deprivation)
- You sleep at the wrong time of day (that is, you’re out of sync with your body’s natural clock)
- You don’t sleep well or get all of the different types of sleep that your body needs
- You have a sleep disorder that prevents you from getting enough sleep or causes poor quality sleep
People commonly increase sleep duration on the weekend to recover from sleep loss incurred during the workweek. Whether ad libitum weekend recovery sleep prevents metabolic dysregulation caused by recurrent insufficient sleep is unknown.
However, a paper published in Current Biology in Feb 2019 indicates that getting extra sleep at weekends probably isn’t enough to reduce health risks related to insufficient sleep during exhausting working weeks, according to a short-term study of young adults.
The team also found that a group of 14 young adults who slept for only 5 hours each night for 9 consecutive nights snacked more after dinner, gained more weight and exhibited reduced insulin sensitivity compared with a control group of adults who slept up to 9 hours each night. In a third group, an additional 14 participants slept only 5 hours per night during the working week but were then allowed to sleep as much as they wanted over the weekend. Even so, during the subsequent week, the negative metabolic effects of sleeplessness persisted.
Furthermore, during recurrent insufficient sleep following weekend recovery sleep, they showed that the timing of the internal circadian clock was delayed, and hepatic and muscle insulin sensitivity were reduced. These findings suggest that benefits of weekend recovery sleep are transient, and they identify lower hepatic and muscle insulin sensitivity and delayed circadian timing as potential negative consequences associated with weekend recovery sleep followed by recurrent insufficient sleep.
The implications being that regular extended periods of sleep in which restful wholesome sleep patterns are repeated is the best way to avoid adverse metabolic, social and neurological events related to sleep discord – relying on extended sleep patterns at the weekend or cat naps during the week to compensate does not at this stage appear to counteract the societal and work related changes driving sleep patterns.