Tossing and turning each night is probably a feeling we’re all used to. So’s staying up late finishing a bit of work or burning the candle at both ends at the weekend. We may not like to admit it, but sleep plays a crucial role in our physical and mental health, and getting enough quality sleep is essential for general health and wellbeing. Sleep is much more complex than you may imagine – even if it feels like you’re doing ‘nothing’. Sleep is an ancient adaptation mechanism common to all mammals and many other organisms whose brain signals the need to stop, recharge and consolidate activities.
Sleep occurs in five stages, wake, N1, N2, N3, and REM. The first four are stages of non-rapid eye movement (NREM) sleep, with each stage being a progressively deeper state of sleep. During NREM sleep, the body begins to repair and regenerates tissues (which is why it’s so important to injury recovery!), strengthens the immune system gradually, and builds bone and muscle. The fifth stage is rapid eye movement (REM) sleep, which is the stage where vivid dreaming can occur.
This stage starts an hour to an hour and a half after falling asleep and counterintuitively is when our brains activity ramps up again into overdrive. As we age, we tend to get less non-REM sleep, and older adults get less deep sleep than younger people. Here, the brain processes and allows the facilitation of memory consolidation, mental focus, and mood regulation. A quarter of sleep time is spent in REM sleep and areas such as the brain stem, particularly the pons and medulla, send signals to relax muscles essential for body posture and limb movement during this stage of sleep.
According to a wealth of recent studies, sleep disruption can have serious consequences on both physical and mental health. Nearly everyone has experienced periods of inconsistent sleep – but the problem is when this becomes chronic. Disrupted or insufficient sleep can lead to chronic inflammation, making individuals more susceptible to chronic illness such as heart disease, high blood pressure, stroke, and Type 2 diabetes. In terms of focus, sleep deprivation can also lead to accidents, including drowsy driving, and has been a factor in some major environmental disasters.
Ever wondered what ‘good sleep’ constitutes? In a study published in The Guardian, ‘good sleep’ was based on five different factors after it was found these behaviours can add years to an adults life.
ideal sleep duration of seven to eight hours a night
difficulty falling asleep no more than two times a week
trouble staying asleep no more than two times a week
not using any sleep medication
feeling well rested after waking up at least five days a week.
In the study, Dr Frank Qian said, “If people have all these ideal sleep behaviours, they are more likely to live longer. So, if we can improve sleep overall, and identifying sleep disorders is especially important, we may be able to prevent some of this premature mortality”. The study included nearly 200,000 participants in the National Health Interview Survey 2013-2018. The study found that, compared with people who had zero to one favourable sleep factors, those who had all five were 30% less likely to die for any reason, 21% less likely to die from cardiovascular disease, 19% less likely to die from cancer, and 40% less likely to die of causes other than heart disease or cancer.
What’s astounding is that those who regularly had all of the above measures for most of their adult lives could live on average 5 years longer for men and almost 2 and a half for women.