Sleep: The Third Pillar of Health


By John A. Caldwell, PhD, MA, BSc

Everyone knows how important good nutrition and routine physical exercise are to health and well-being.  But did you know that sleep is just as important if not more so?  Not only is this a well-established fact in the scientific literature, but any quick Google search readily proves that sleep is considered the third pillar of health! Unfortunately, despite the long-held belief that “sleep is for sissies” the past two decades of research have shown beyond a shadow of a doubt that sleep is essential for health, performance, and safety.

Why do we sleep?

Believe it or not, scientists still aren’t exactly sure why we need to sleep.  In some ways sleep is a rather puzzling behaviour since you can’t eat or drink while sleeping, you can’t reproduce while sleeping, you can’t monitor the safety of your environment while sleeping, and back in caveman days, you were vulnerable to attack by predators while sleeping.  In light of all of these disadvantages, it seems that mother nature would have eliminated our need to sleep since it seems so contrary to survival!  However, the fact that evolution hasn’t eliminated our need for sleep makes it clear that sleep is so vital for survival that neglecting it can kill us! In fact, it is now well-known that insufficient sleep degrades the immune system, saps our energy, allows the build-up of brain toxins, and impairs both learning and memory.

How much sleep do we need?

Based on a plethora of research, there is now worldwide agreement that adults need 7-9 hours of sleep every night in order to be their best.  And teenagers need even more!  In fact, the younger you are, the more sleep you need. The current recommendation for teens is 8-10 hours per night and younger school-age and preschool children need anywhere from 9-13 hours per night.

How much sleep are we getting?

Unfortunately, more than a third of both Aussies and Americans are failing to get the recommended amount of sleep on a day-to-day basis.  Night workers are even more sleep deprived.

Why aren’t we sleeping enough?

It turns out there are lots of reasons we don’t get enough sleep, but 5 seem almost universal at this point: 1) poor sleep habits, 2) bad lifestyle choices, 3) work obligations, 4) sleep disorders, and/or 5) other medical conditions.  Things like working or watching TV in the bedroom, using too much alcohol or caffeine, sacrificing sleep to cram in extra work, and especially for overweight men, developing conditions like sleep apnea or Type II diabetes, all either separately or in combination, contribute to our growing sleep debt.

What happens when we don’t get enough sleep?

Over the past 2 decades in particular, the list of problems that have been definitively associated with insufficient or disordered sleep has grown so long that we could write a whole book about it.  But in short, it is now well-known that inadequate sleep not only impairs performance and safety at work, but it increases the risk of neurological disorders like Alzheimer’s, Parkinson’s, and Huntington’s disease; health problems like obesity, diabetes, hypertension, and cancer; and even mental disorders like depression anxiety, alcoholism, and PTSD. Even more scary is the very real possibility that even intermittent sleep restriction or sleep deprivation probably results in lasting damage to the brain!

So, what can we do to get better sleep?

Given all of the problems associated with not sleeping enough, you might think it’s really complicated to fix our growing sleep debt, but the reality is that it’s pretty straightforward. It all comes down to 1) making sleep a priority (it makes you smarter, happier, and healthier); 2) improving your sleep habits (using the bedroom for only sleep-conducive activities, avoiding e-readers, smartphones, and computer work close to bedtime); and using your Fitbit, Apple Watch, Garmin, or other sleep/activity tracker to monitor and improve your sleep routines.

In summary

Remember that sleep is an ancient behavior that mother nature still considers very important; we as adults need a minimum of 7 hours per day (and many need up to 9 hours a day); and chronically neglecting sleep leads to permanent brain damage, poor physical and mental health, and increased likelihood of an early death. But all of this easily can be avoided by making sleep a priority and following the good sleep habits suggested by the Australian Sleep Health Foundation, and the U.S. National Sleep Foundation.  Or, you can just do a Google search for “Good Sleep Habits” and check out the recommendations made by any number of other organizations.  Remember– Better sleep = A Better Life!


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