Why is Sleep so Important? My Top 4 Reasons

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Why Is Sleep Important, And Should I Be Worried?why is sleep so important

I feel that in running a website about choosing a mattress to help you sleep well, I have a responsibility to talk about sleep related topics with you. One of the most important things I could ever discuss with you is therefore “why is sleep so important?”.  There are many, many reasons, and they affect every aspect of your life.

We all know that we feel tired and grouchy if we don’t get enough sleep. But do you really know why it matters so much? Sleep plays a massive role in our health and well being. How we feel when we are awake is largely influenced by the quality and quantity of the sleep we get. How to get more sleep and causes of poor sleep are covered in separate articles here at BestMattressForYou.com. In this article we’re just focusing on the WHY as it is a big topic just on its own.

I’ve chosen what I consider to be the big four reasons and outlined each below. It’s important to note that any negative effects of missing sleep are mostly to do with chronic lack of sleep. If you miss a couple of hours sleep tonight but usually sleep well, don’t worry! You might feel grumpy tomorrow but you won’t be at a higher risk because of it.

Top 4 Reasons Revealed

#1. Sleep protects your physical health

Quality sleep protects against many health issues.

Adults who do not get enough sleep are at increased risk of

  • obesity
  • diabetes
  • heart disease

To name just a few. Let’s take a quick look at each condition separately.

Why the increased risk of obesity?

There are many complex and interlinked reasons why poor sleep is related to obesity, so I’ll explain just one you might find interesting. Like many many processes in our body, our hunger and drive to eat is controlled by hormones. Namely, ghrelin (which makes you feel hungry and want to eat) and leptin (which signals when you have had enough to eat). In my previous job as a health professional, I used to call ghrelin the hungry monster. Not getting enough sleep can increase the level of ghrelin hormone, turning you into a hungry monster! It’s very difficult for us humans to avoid eating if we are feeling hungry. It’s part of our make up (and willpower has nothing to do with it). Do you feel tired and hungry all the time? Poor sleep interfering with your ghrelin levels could be the culprit.

  • Scary fact: a really large, good quality clinical study found that adults with short sleep times are 55% more likely to obese than those with longer sleep times.

Why the increased risk of diabetes?

Being overweight puts a person at increased risk for diabetes, so not getting enough sleep can be a slippery slope from one thing to another. The main reason, however, is that lack of sleep actually changes the way our body processes sugar. The “need to know” info is that it reduces your sensitivity to the hormone insulin. Insulin has a number of jobs to do inside our bodies. One of its most important jobs is to help sugars from the food we eat get from our bloodstream into our cells to be used for energy. If our cells are not sensitive to insulin, the sugar stays in our blood. Diabetes is defined by having high blood sugar levels.

Why the increased risk of heart disease?why is sleep so important

Again, heart disease can go hand in hand with obesity and diabetes. Obese or diabetic people are at greater risk of heart disease. But just like we saw above, lack of sleep can increase the risk of heard disease all by itself, too. This is because it can cause an increase in blood pressure, heart rate, and chemicals that cause inflammation. These are all risk factors for heart disease because they are bad news for the lining of your blood vessels. Our blood vessels are prone to damage from these things, and damage often leads to blockage.

As well as helping to avoid these big scary diseases, better sleep means better immune system function too, so you’ll be less likely to catch a cold.

#2. Sleep protects your mental health

If we get a good nights sleep, we’re more likely to  feel good emotionally. It’s common for people get cranky if they skip sleep, but chronic sleep deprivation can actually lead to anxiety and depression.

This can be a really vicious cycle. Poor sleep can lead to depression, and people who suffer with depression are less likely to get good sleep. The exact mechanisms of why poor sleep contributes to depression and/or anxiety are yet to be explained. However, we do know that our brain does a lot of “repair and refresh” work during sleep so it’s no great surprise.

#4. Sleep keeps you safe

As you will read below, sleep helps your brain work properly and make better decisions. These are also factors that can help keep you safe in a variety of situations. Whether it’s behind the wheel of a car or at work, if you are tired you could be dangerous. Even in my own circle I know two people who have fallen asleep while driving and crashed their cars. Thankfully both lived to tell the tale and did not hit other cars but their own cars were pretty banged up and it was very scary.

In fact, tiredness and fatigue increases the chance of a workplace accident by 30%. Another scary fact is that sleep deprivation can have the same effect on driving as a blood alcohol level of 0.08% (which is considered legally drunk in the United States of America).

#5. Sleep helps your brain work properly

It has been shown over and over that people who have not had enough sleep have all sorts of problems across their day. People become slow at completing tasks. They are more likely to make mistakes (and more of them) and can’t react quickly if needed. Communication deteriorates and people are easily distracted. It is therefore not surprising that people who aren’t getting enough sleep aren’t very safe as explained above!

I know from my own experiences of being up at night with my babies that not getting enough sleep had a profound effect on my brain. It made me so crabby (SO SO crabby), I couldn’t concentrate on anything, and I got emotional very easily. It felt like I was in a bit of a fog. I took some comfort in knowing that this was a short term phase as I navigated life with a new baby. I am so glad they both now sleep through the night (most of the time).

On the other hand, good sleep leads to improvements in learning new information, being creative, and making decisions. So maybe people who say “I’ll sleep on it ” when they’re trying to decide something are on to something!

Fun fact: Usain Bolt would nap before world record attempts, looks like he was on to something too!why is sleep so important

There are many other reasons…

There are loads of other reasons that I have not covered. These include fertility, sex drive, helping children grow and learn, helping adolescent brain development, and regulating your body temperature to name just a few. You may find that some of these reasons are more of a priority for you than the ones I have selected above. I have tried to select and explain four things that I think will resonate with the widest range of my readers and provide the most helpful information.  They are the broadest and most overarching factors, but that does not mean these other reasons are less important. If you would like to comment on some of the other reasons (or discuss the ones I covered) please leave me a comment. I always love to hear from my readers.


Emily Johnstone

Emily is the creator and owner of bestmattressforyou.com. Emily's scientific background gives her an analytical, critical, and discerning eye to bring unbiased, thorough, and helpful content to the site. Your good sleep is her top priority. Find out more about Emily and bestmattressforyou.com here.