What happens when we don’t sleep?

Learn how powerful sleep is and why it is the bedrock of all healthy habits. In this post, we investigate the science behind sound slumber and the dangers of neglecting sleep.

How can sleep influence your brain health?
Scientific Evidence*
Impact on Brain Health**
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What do The Flintstones have in common with your sleeping habits? 

For one, when you don’t get enough sleep, you can feel as if you’ve been clubbed over the head by a caveman. But more importantly, just as the characters from this 1960s cartoon lived in Bedrock city, sleep also happens to be the bedrock of all healthy habits. 

Sleep plays a vital role in maintaining overall health and wellbeing, and its benefits extend far beyond simply feeling rested. Getting enough sleep, and going to bed and waking up at the same time each day, is essential for physical and mental restoration, cognitive functioning, and emotional balance.

Good sleep is the bedrock for healthy habits

If your sleep is less than optimal, you’re going to find it difficult to achieve balance in other areas of your life.

After a poor night’s sleep, people are more likely to act impulsively and favour instant reward over waiting for a better outcome. 

Alcohol-induced hangovers highlight this effect pretty clearly. 

Many of us have been there. That following morning you are still tired, groggy and definitely in no position to make responsible or healthy decisions.

In this state, our bodies are dehydrated and depleted of essential nutrients. But because alcohol impacts the quality of our sleep, the healthy food choices we need to make to counter its effects are often the first thing to go out the window.

The impairments caused by a single night of bad sleep far eclipse those of a day without food or exercise. 

What happens after one night of poor sleep?

If you want to know why sleep matters, it’s worth looking at the consequences of a lack of it. 

Even one night of poor sleep, to be precise.

1.Poor sleep is as unsafe for driving as driving drunk

After a poor night’s sleep, cognitive performance takes an immediate hit.

In fact, fewer than six hours of sleep raises your odds of a car crash by 1.3 times, while fewer than four hours of sleep makes a car crash 15 times more likely, similar to the risk of someone who has had nine alcoholic drinks.

2.Daylight savings time: a risky shift for heart health

The switch to daylight savings time in March results in a loss of one hour of sleep. Correspondingly, patient records show an alarming spike in heart attacks the following day.

3.And all of this as well…

And in the longer term…

Science is now learning that there is a significant relationship between a lack of deep sleep and dementia, particularly Alzheimer’s disease.

Insomnia and sleep apnea (heavy snoring) are also associated with a significantly higher risk of developing the condition in later life. Why? Because both conditions can interfere with deep sleep.

Researchers have only recently started to unpack the mechanisms behind the relationship, and they’re pretty fascinating.

It was discovered a few years ago that the brain has a cleansing system that flushes toxins out and only operates during sleep. 

It’s called the glymphatic system and it operates much like a dishwasher, giving the dirty cutlery you accumulate through the day a deep rinse while you rest, so that you can wake up to clean and shiny eating utensils. 

We see that waves of fluid flow into the brain during deep sleep. This fluid seems to wash beta-amyloid from the brain, which is a sticky, toxic substance that builds up and goes awry in Alzheimer’s disease. 

Indeed, long-term studies have confirmed that older adults who get less deep sleep have more beta-amyloid, as less sleep means less clear-up time.

Now this has been an exciting and hugely important finding, because there’s actually a lot we can do about our sleep. We’ll be sharing how in our next articles.

What's the connection between sleep and Alzheimer's disease? | Sleeping with Science, a TED series

What’s next?

Now that you’re hopefully convinced to take sleep seriously, it’s time to move on to our articles and exercises that will provide science-backed techniques to upgrade your sleep.

Ready to get more from your nights of sleep? 

If you haven’t had a chance yet, make sure to download the Five Lives app today!

Keep following along for all our best tips, tricks and tactics to improve your sleep.

Let’s all work together to add life to your years.

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What happens when we don’t sleep?

Learn how powerful sleep is and why it is the bedrock of all healthy habits. In this post, we investigate the science behind sound slumber and the dangers of neglecting sleep.

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