Why do we sleep?
At its most basic, sleep is a biological process that plays a vital role in physical, mental, and emotional health. Sleep enables our bodies to perform vital functions essential for our physical and mental wellbeing, resulting in a range of benefits.
During sleep, our brains and bodies are very busy. It is when we process memories and emotions, and repair and renew. It is absolutely essential; eventually, no matter how hard we fight it, we will want to sleep for at least part of every 24 hours.
What causes us to sleep?
Circadian rhythm
Also known as our body clock. It runs on a roughly 24-hour cycle. Our body clock is influenced by external agents, or “time givers”. These are elements in our environment that provide the stimulus to set or reset our body clock. Examples of time givers include light, meal times, social activity, and exercise.
Sleep drive
Also known as sleep pressure. This is the process that makes us feel sleepy. The longer we go without good quality sleep, the higher our sleep drive. We can support our sleep drive being at its peak at bedtime by getting plenty of exercise and activity during the day, and avoiding naps.
Night Owl or Morning Lark
Knowing where your body clock naturally sits within a given 24-hour period can make a difference when trying to get a good night’s sleep. Some of us naturally have a lot of energy first thing in the morning, while others come to life in the evening. And many people are somewhere in between.
It does not mean (as is often implied) that night owls are lazier because they don’t come to life until later in the day. It all comes down to our internal body clock and the natural release of hormones, cortisol and melatonin, which control the body clock.
Your sleep needs
How much sleep do we need?
The recommended amount of sleep for adults can vary based on a range of factors, including age, gender, lifestyle, and health issues.
Studies have suggested that the average adult needs 7–9 hours of sleep. However, everyone is slightly different; some people will need slightly less or slightly more than the recommended amount.
Sleeping less than 6 hours is considered not enough sleep for most adults. Conversely, regularly sleeping more than 10 hours per night may be a symptom of an underlying health condition and should be investigated by your GP.
