Introduction

The importance of skin health and regeneration

Your skin is the largest organ in your body and is made up of fat, water and metabolic products. The skin is the first line of defence, protecting your body from bacteria and viruses. Your skin allows you to feel the sensation of warmth, coldness, pressure, itching and pain. These sensations tell us that something is wrong and that we must do something to avoid that sensation. For example, touching a hot radiator triggers a reflex to pull our hand away.²

Have you ever taken a fall and accidentally cut your skin? Have you noticed that the wound eventually scabs over and leaves a scar? This process is called skin regeneration. When your skin is injured, your blood supply increases to help stop the bleeding. There are a number of different cell types that are involved in helping heal the wound.¹ This process generally takes 4 to 6 weeks, but may take longer for chronic wounds. When we are injured, prioritising rest increases our chances of recovery; therefore, sleep is an important factor in skin repair.

The significance of sleep for overall well-being

Sleep is a necessity for good well-being. Adults generally need 7 to 9 hours of sleep to function well and stay healthy. If you get inadequate sleep for a long period of time, you risk developing long-term health problems such as heart disease, diabetes, high blood pressure, obesity and depression. You may feel more stressed, angry, mentally exhausted and find it difficult to focus. During our sleep, the body repairs cells, releases vital hormones, forms and stores long-term memories, and removes toxic wastes in the brain. By prioritising our sleep hygiene, we can lead healthier and more fulfilling lives.³ 

The relationship between sleep patterns and skin regeneration

You can expect that inadequate sleep will have an impact on our skin health and regeneration. Poor sleep has been linked to dull skin and visible signs of ageing. During our sleep, hormones and growth factors are produced to help repair damaged skin cells. When you don’t get enough sleep, it reduces the ability of your skin to repair and rejuvenate. An increase in stress caused by sleep deprivation can cause inflammation of the skin that could result in acne and itchy skin. The importance of good sleep hygiene is very important for the normal functioning of the body.

In this article, we discuss how sleep works to repair and rejuvenate our skin. We also give some practical tips to help you get that beauty sleep.

The basics of skin regeneration

The skin's role as a protective barrier

Your skin is composed of three layers: the epidermis (outermost layer of the skin), dermis (the middle layer of the skin that supports the epidermis), and the hypodermis (the bottom layer of the skin, made of fat and stores energy). All these layers of the skin work together to protect the body from pathogens, UV light and mechanical or physical injury. It also helps regulate homeostasis by holding fluids in, preventing dehydration, and regulating our temperature.⁴

The skin regeneration process

The skin is constantly replacing itself approximately every 27 days. This is why scars take a while to fade. There are four overlapping phases that occur in skin regeneration:

1. Haemostasis – begins several hours after injury
   1. Exposure to collagen triggers platelets (a special type of blood cell that helps with clotting) to build up and close the blood vessels to reduce bleeding. It is soon followed by vasodilation (dilation of blood vessels), allowing white blood cells and (thrombocytes) to flood in to help with the wound healing process¹
2. Inflammation
   1. The innate immune system (first line of defence) responds to the injured site. They recruit a number of immune cells, nutrients and enzymes and growth factors during this phase. At this stage, redness, pain and heat can be seen or felt. It is during this phase that collagen creation begins. Collagen helps strengthen the elasticity of the skin, keeping our skin hydrated and youthful⁵ 
3. Proliferation
   1. This stage is where the wound begins to “close”. It’s essentially where the skin is restored with a new network of blood vessels and a formation of granulation tissue (a type of connective tissue made up of collagen and extracellular matrix that’s specifically formed during the wound process)¹
4. Remodelling
   1. This is the final stage of the wound-healing process. It begins with the development of granulation tissue, which matures into a scar. The formation of new blood vessels decreases. The aim of this stage is to increase tensile strength. This means the maximum stress your skin can take before it is damaged⁵

It is important to recognise the two distinctions between skin repair and regeneration during wound healing. Skin repair refers to healing existing tissue, while skin regeneration replaces damaged tissue with new tissue.⁵

The significance of sleep

The importance of sleep for various bodily functions

We spend a third of our lives sleeping, yet most of us don’t get the quality of sleep we need. Sleep is important in maintaining good health. Muscles relax, the heart rate slows down, and toxins that build up in the brain are removed. The amount of sleep you need depends on your age and how you feel when you wake up. Younger children may need 9-11 hours. Teens and adults may need 7-10 hours of sleep. If you’re struggling with sleep, it’s best to seek assistance from a doctor as good quality sleep can prevent a number of chronic diseases. 

Sleep cycles: REM and non-REM sleep

Sleep is more than just nodding off and counting sheep; it is a dynamic and complex process that affects all systems of the body so that we can stay healthy, process new information, and feel rested. In order to achieve quality sleep, we go through stages of rapid eye movement (REM) and non-REM (NREM) sleep.⁶ 

NREM sleep can be further subdivided into three stages:⁶

1. Light sleep 
   • A person may easily be awoken at this stage. This stage lasts around 1-7 minutes. Your body begins to relax
2. Deep 
   • NREM stage 2 is a much deeper sleep stage than stage 1 and lasts around 10- 25 minutes. A person can still be awoken at this stage, but with heavier persistence.  Brain activity is slow. Memory formation is thought to occur in this stage. At least 50% of your sleep happens at stage 2
3. Deeper sleep 
   • The final stage of NREM sleep where a person is in deep sleep. The body begins repairing tissues, strengthening the immune system and building bone and muscle. If a person is woken up at this stage, they may feel groggy afterwards

REM Sleep:

• This phase begins 90 minutes after falling asleep, and it is at this stage that dreaming occurs. Your muscles are temporarily paralysed to prevent you from acting out your dreams. Many of your bodily functions, like your breathing and heart rate, are almost as active as when you’re awake.

After the initial cycle is complete, the cycle repeats for a total of 4 - 5 cycles in a night. By depriving ourselves of sleep, we reduce the ability of our bodies to release essential hormones necessary to repair tissues. 

Circadian rhythms

The circadian rhythm is an internal clock that tells us when we’re awake and when we’re sleepy. Your body’s biological clock follows a 24-hour cycle and synchronises with environmental cues. Examples include the sunlight telling our bodies that it’s time to wake up and a dark and cool room suggesting that it’s time to wind down. A hormone released from the pineal gland (tiny tissue in the brain) called melatonin regulates our sleep-wake cycle. Your levels of melatonin are the highest at night and then fall back to normal during the day. It acts as a cue for our body that it’s time to sleep.⁷ 

Sleep patterns and skin health 

Disruptions in our sleep patterns can be caused by a variety of stressors in our lives, such as our jobs, travel or our sleep habits. 

Disrupted sleep can increase stress and inflammation in your body, resulting in chronic diseases and decreased concentration levels.⁸ Signs of inadequate sleep appear on your skin as:⁹

• Fine lines 
• Dull skin
• Dark eye circles
• Red eyes
• Droopy corners of the mouth 

As we age, our sleep patterns change, and most people find it more difficult to fall asleep. If you have trouble falling asleep for more than two weeks, you should see your GP. They may prescribe you with melatonin medicines. Examples include Circadin, Adaflex, Ceyesto, Slenyto and Syncrodin. 

Practical tips for healthy sleep and skin

The current data shows that sleep has become less of a priority among adults. Healthy skin is typically a sign of good health. It’s incredibly important to prioritise sleep in order for your body to repair tissues effectively and overall reduce the risk of life-threatening conditions.¹⁰

Here are some recommendations to improve your sleep quality: 

• Create a relaxing sleep environment
  • Make sure the temperature is right for you and that it is well-ventilated. An ideal bedroom temperature is roughly 16-18°C
  • You may find it helpful to wear earplugs or a sleeping mask to avoid any disruptions caused by the environment
• Avoid caffeine after 1 pm 
• Stick to a consistent sleep schedule (i.e. wake up at the same time and go to bed at the same time every day, even on the weekends)
• Soak in sunlight for thirty minutes 
• Exercise for at least 30 minutes, but avoid strenuous exercise 1 or 2 hours before bed 
• Avoid large meals before bed
• Avoid blue light for 1-2 hours before bed
  • Blue light has been found to block the release of melatonin.
• Maintain a healthy diet by incorporating fibre, carbs, protein and vegetables in your diet
• Avoid alcoholic drinks before bed
• Don’t lie in bed awake
  • This causes our brain to associate our bed with wakefulness. If you find yourself lying in bed for more than 15 minutes, try and get out of bed and do some relaxing activities until sleepiness kicks in

Summary 

Sleep is an important process for maintaining good health. During our sleep, our tissues are repaired and toxic wastes are removed from the brain, so we can feel well rested. When you consistently have a good quality of sleep, it shows in your skin. Your skin appears rejuvenated, healthy and brighter. Not only does good sleep have a positive impact on your body, but you also feel more rested and have an easier time concentrating. It can be difficult to prioritise sleep as we get older because of the many challenges life may throw at us, such as school, family and relationships, jobs and being a new parent. If you have trouble sleeping and none of the above tips has helped and is affecting your daily life, it's best to consult your doctor to help overcome your problem.