Approximate read: 4 minutes. 

I’ve recently finished reading a 360 page book on sleep.

Yup. You read that right. 360 pages on just slumber. It’s called “Why we sleep” and it’s written by a sleep researcher named Matthew Walker. If you’re silly, like me, you’ll also find it funny that he is a sleep researcher and his last name is “Walker”. As in “sleep walking”. Get it?


This book was not the easiest read in the world, but some of the stuff in there absolutely blew my mind. I’m now also completely convinced of the crucial importance of sleep for our well being and health. 

This is a 2-part series (because the original article became way too long and I know we all have the attention span of a toddler these days). In part 1, I share some cool facts about sleep, as well as shed some light about the link between sleep and weight loss. In part 2, I go over 12 tips for a healthier sleep.


Some cool facts about sleep 

  • You are genetically programmed to be either a night owl or a morning person. Yup – it’s programmed into your DNA.
  • Babies spend most of their time in the womb asleep – including that time you think they are kicking because you did something. Sorry parents!
  • The last 2 hours of sleep, which typically occur in the wee hours of the morning, are crucial for REM sleep (the type of sleep where you dream). Rob children and teens of these crucial few hours and they exhibit behaviour patterns that are frighteningly similar to the symptoms of ADHD.
  • During the teenage years, the circadian rhythm of a teen shifts so that they literally cannot fall asleep until the late hours of the night. It’s also why they need more sleep in the morning.
  • The human brain needs a reset after 16 hours. If you are awake for longer than 16 hours, your brain starts to fail
  • A human needs 8 hours of sleep. Anything less than that (even 1 hour) has serious health consequences.
  • The chances of you being “that person” who only happens to need 6 hours of sleep, are zero!
  • Alcohol acts as a sedative. After you drink, you are not getting the same kind and quality of sleep as when you fall asleep naturally.
  • Driving on only 4 hours of sleep has the same effect as if you were legally drunk: you are 6x more likely to get in a car accident
  • Drowsy driving causes more crashes than drunk driving. Combine 4 hours of sleep with one or two drinks to the point of being legally drunk, and you are now 30 times more likely to be involved in a car accident.


Sleep and weight loss

You’ve likely heard before about the importance of sleep on weight loss, but you likely don’t fully understand the connection. To be honest, I didn’t fully understand it either until I read the book, and now I do, so here it goes: 


Your food-related hormones get out of whack

When you don’t sleep enough, two key food-related hormones get out of whack: one controls your feeling of “fullness” and one controls your feeling of “hunger”. In people who only got 5 hours of sleep, the amount of “fullness” hormone went down, and the amount of “hunger” hormone went up. This means that when you are sleep deprived you are less capable of controlling your cues for hunger and fullness.


You eat more, and it’s mostly crap

Not surprisingly, then, when you are sleep deprived, you eat more. One study showed that, after sleeping for only 4.5hrs, participants ate 300 calories more each day! The same effect occurred when people were sleep deprived by only 2-3 hours of sleep over 10 days – a scenario that’s very real for many of us. Sleep deprived people also reached for different types of food –  sweets, heavy carbs (bread and pasta), and salty snacks were all very popular choices.

So why is that? Why are we more tempted to reach for crap when we’re sleep deprived? The underlying reason is a silencing of brain regions that control our impulses. As such, we’re more impulsive and less capable to control our cravings.


If you lose weight, it will mostly come from muscle (not fat)

If you have some sort of weight loss goal this nugget will be particularly important to you: when you are not getting enough sleep, the body is particularly reluctant to give up fat and more than 70% of your weight loss will come from muscle! Which sucks, because all that exercise you’re doing is trying to build muscle. So make sure you get your ZZZZs.


Sleep and exercise

If you’re suspecting that there is a link between sleep and exercise, you’re right – there is: but it’s not as strong as you might think.

For example, people did not always sleep better on days they exercised versus days they didn’t. However, the length and quality of their sleep did improve over time. The time it took people to fall asleep also decreased.

That being said, when people had a good night sleep, the intensity of their workouts was higher and they were more likely to engage in physical activity. Their energy was also higher overall.

Here’s another way to think about it: the less sleep you get, the less energy you have, which means you are less likely to exercise – and more likely to eat crap. 



The importance of sleep is totally underrated! Sleep is a tool that we all have at our disposal to help us stay in good health, reduce our risk for many disorders, and keep our weigh loss and cravings in check. In the second part of this series, I’ll go over 12 tips that you can implement for a healthy sleep.


Want to set some sleep related goals?

My Ultimate Guide to Goal Setting will take you through a blueprint where you can come up with goals that you will actually want to achieve:

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More stuff for you to read:

The secret behind how to create motivating fitness goals

Is your personality sabotaging your fitness goals?

Fitness lessons: What exercising teaches you about life

5 ways to motivate yourself to work out