Why do we need sleep?
Sleep is an essential part of our survival - just like food and water, we need sleep (and the right amount) to thrive. That’s why the average human spends about one-third of their life asleep. While we’re asleep, our brain is working hard and triggering many different biological processes, such as sending signals to the body to repair cells, restore energy, and release hormones and proteins.
So, why do we need sleep?
Sleep is a well-studied area, but there are still a lot of unknowns when it comes to the purpose of sleep. However, there are a number of scientific theories that suggest there are biological reasons for getting some shut-eye.
Energy conservation theory
Energy conservation theory suggests that one of the most important reasons that we sleep is to reduce our body's energy expenditure. When we sleep, our metabolism is significantly reduced - by as much as 10%. This is due to a reduction in our body temperature and caloric demand during sleep.
The theory is that our bodies have developed this biological process over thousands of years, because one of the biggest factors in natural selection is being able to effectively utilise energy and resources.
Repair and restoration theory
According to the repair and restoration theory, sleeping is crucial for restoring the psychological processes that keep our mind and body healthy. Sleep allows cells to repair themselves. These kinds of processes include repairing muscle, tissue growth, releasing hormones and synthesising protein.
Brain plasticity theory
The brain plasticity theory suggests that sleep is essential for brain function - it allows time for your nerve cells to reorganise. The part of your brain that is in charge of clearing waste removes toxic byproducts from your brain, which build up throughout the hours you’re awake. Clearing this waste allows your brain to function well when you wake back up.
Sleep affects many aspects of brain function, such as:
Focus
Creativity
Learning
Memory
Decision making
Maintaining proper insulin function
Insulin is a hormone that helps your body turn glucose into energy. But if your body doesn't properly respond to insulin, it can lead to high glucose levels in the blood and eventually type 2 diabetes.
The brain uses less glucose during the hours you are asleep, which helps your body regulate the amount of glucose in your blood.
Can lack of sleep affect your memory?
Without sleep, the brain can struggle to function as it normally does. The neurons in your brain will become overworked if they don’t have time to recuperate, and will be less capable of maintaining optimal performance.
Poor sleep comes in many different forms, including fragmented sleep and insomnia. These sleeping problems will have some short term impacts on your cognition. Lack of sleep will poorly affect your working memory, which is needed to remember things for immediate use. Both REM and Non-REM sleep have proven to be important for strengthening your broader memory. People who are sleep-deprived are also at risk of developing false memories.
REM sleep is believed to improve procedural memory, like remembering a sequence of steps. Whereas NREM sleep has been linked to improving declarative memory, which includes things like statistics and basic facts.
How does sleep affect reaction times?
Getting enough sleep consistently is a vital element in maintaining both your mental and physical health. If you sleep poorly or aren’t sleeping as much as you should, you begin to accumulate a sleep debt.
Sleep debt - also known as sleep deficit - is the difference between how much sleep you need, and how much you actually get. If you’re sleeping fewer hours than your body requires, the hours you miss out on get added to your sleep debt.
A person's reaction time worsens the more sleep debt they accumulate. So the more sleep they miss out on, the longer it’s going to take them to react to a stimulus. Some believe the reason our reaction times worsen when we’ve underslept is because of the body’s competing needs. When we’re underslept, our body is experiencing a need to sleep, a need to stay awake, and the need to perform tasks. These competing needs will interfere with our attention from moment to moment, leading to cognitive impairment increasing our reaction time.
How does sleep affect creativity?
Lack of sleep is linked to poor cognitive function. This includes poor focus and concentration, reduced creativity, increased erratic behaviour, difficulty multitasking, and increased likelihood of making mistakes. It’s no surprise then, that a lack of sleep can impact your ability to think creatively and effectively.
REM sleep is particularly important for boosting creative ability. REM sleep helps with pattern recognition, which allows the brain to connect unrelated ideas, and greatly improves creative problem-solving.
Key takeaways
Why do we need sleep? Sleep is an essential part of our everyday lives. It helps us regain energy, repair our bodies, repair our minds, and vastly improves brain function. Without sleep, our minds and bodies will swiftly start to feel negative effects.
Can lack of sleep affect your memory? If we become sleep deprived, our brain function and cognitive levels drop dramatically. Regular REM sleep helps our brain remember long sequences, and NREM sleep helps us remember more basic things like statistics or basic facts.
How does sleep affect reaction times? If you accumulate sleep debt and are feeling run down, this will negatively affect your reaction time. This is because of the three different competing factors that are happening in your body. The need to stay away, the need to sleep, and the need to perform a task.
How does sleep affect creativity? Lack of sleep negatively affects your cognitive function. This will cause you to have poor focus, poor concentration, and difficulty multitasking, All of these functions are essential when it comes to creative thinking and problem-solving.
IF YOU’RE EXPERIENCING PERSISTENT DISRUPTIONS TO YOUR SLEEP, CONSULT WITH A PHARMACIST OR TRUSTED MEDICAL PROFESSIONAL TO DISCUSS POSSIBLE SOLUTIONS.
Any advice provided in this content is of a general nature and does not take into account your objectives, health or needs. The information in this post is not intended to substitute medical advice, diagnosis or treatment and should not be exclusively relied on to diagnose or manage a medical condition. You need to consider the appropriateness of any information or general advice we give you, having regard to your personal situation, before acting on our advice or purchasing any over-the-counter sleep product.