Sleep is an essential process that plays a crucial role in supporting cognitive functions, mental health, physical well-being, and recovery. Insufficient sleep can harm your health and raise the risk of various diseases.
Discover more about the importance of sleep and how it affects the body in our article, where we also provide practical tips to improve your sleep quality and help you rest longer.
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How sleep works
Stages and Phases of Sleep
The Importance of Sleep
Practical ways to get more sleep
How Sleep Works
Two primary processes determine how and when you sleep: sleep-wake homeostasis and the circadian rhythm. Both are managed by different brain areas and involve several hormones and chemicals, like melatonin.
These processes are essential for maintaining good sleep health, yet they’re easily influenced by lifestyle habits and your sleeping environment. Factors like caffeine, long naps, and screen use before bed can disrupt the body’s ability to relax and prepare for sleep. If falling asleep is challenging, try the practical tips shared below.
Sleep-Wake Homeostasis
This process refers to the increasing need for sleep as awake time lengthens. Essentially, the longer you stay up, the more your body will crave sleep. After adequate rest, this need decreases, allowing you to feel refreshed and alert. Sleep-wake homeostasis works alongside the circadian rhythm to maintain a balanced sleep cycle.
Circadian Rhythm
Your body has an internal clock that naturally responds to light changes, regulating sleepiness based on the time of day. Ideally, exposure to morning light helps trigger wakefulness, while darkness signals the need for rest.
This rhythm, controlled by hormones and brain functions, can be affected by external factors like diet, exercise, stress, and daily habits—particularly light exposure in the bedroom. Discover more about how to improve your sleep quality.
Stages of Sleep
The initial stage, N1, lasts only a few minutes as you start to drift off. During this phase, your heart rate and breathing slow, and your muscles begin to relax.
Stage 2 (N2)
As sleep deepens, you enter the second stage, N2. In this stage, body temperature lowers, and brain activity shifts, producing sleep spindles. This stage is considered light sleep, from which it’s easier to wake. If taking a nap, aiming to wake during light sleep can help you feel refreshed.
Stage 3 (N3) – Deep Sleep
The third non-REM stage, N3, is deep sleep, also called slow-wave or delta sleep. In this phase, the brain produces delta waves, and the body enters a deep state of relaxation. This stage supports growth, recovery, tissue repair, cell regeneration, and immune health, making it crucial for restorative sleep and overall well-being.
REM Sleep
The final stage, REM sleep, is marked by rapid eye movements and vivid dreams. During REM, brain activity intensifies, and the body undergoes temporary muscle paralysis. This stage is important for memory processing and problem-solving.
The importance of sleep
Sleep is vitally important for your health and wellbeing. It is crucial for childhood development, with children requiring more sleep than adults as they grow. Most adults need 7-9 hours per night to have sufficient rest. Sleep supports the body and brain in several fundamental ways regardless of age.
Regular and sufficient rest allows the brain to consolidate memories, process information, and engage in problem-solving and decision-making. It supports cognitive function and mood, aids concentration and learning, and can improve some mental health conditions such as depression and anxiety. Sleep also promotes emotional regulation and improves your response to stress.
In addition, sleep strengthens your immune system, helping you to fight off infection and disease. It regulates hormones and supports metabolic health, playing a role in weight management. Sleep also influences your body’s ability to heal, triggering tissue repair and cell regeneration in deep sleep.
What are the negative effects of not getting enough sleep?
The effects of insufficient sleep may be felt immediately or they may be more long-term, impacting your life and general health.
For instance, according to Better Health, “staying awake for 24 hours leads to a reduced hand-to-eye coordination that is similar to having a blood alcohol content of 0.1.” Skipping even one night of rest can result in workplace injuries and accidents on the road.
Consistently missing out on sleep can lead to:
- Weight gain
- Mood swings and irritability
- Reduced libido
- Difficulty with memory and focus
- Problems with balance and coordination
- High blood pressure and increased stress sensitivity
- Lowered immunity, making you more prone to infections
- Higher chances of developing diabetes and heart disease
Practical tips to sleep more and better
According to our 2024 Sleep Census, only 8% of people worldwide wake up feeling refreshed every morning. There are a number of ways you can promote the quality of your sleep.
For more tips, read our guide: How to get better sleep
