Regular Sleep-Wake Cycle

Circadian rhythms or sleep-wake cycle spans the 24 hours of a day. During these 24 hours, an individual is supposed to sleep for almost 8 hours and stay awake for the remaining 16 hours. Our circadian rhythms used to be linked with the light of the day and the darkness of the night. 

The time and light acted as stimulants for the body to know whether it is time to sleep or stay awake. However, technology and other environmental and lifestyle habits have disrupted our regular sleep-wake cycles. 

This change majorly affects sleep time because we are constantly surrounded by artificial light. This tells the hormonal system of our body that it is time to stay awake. Before we jump into the aspect of REM sleep, we need to discuss a normal sleep routine and stages of sleep. 

A regular and healthy sleep cycle consists of 8 hours of consistent nighttime sleep in a day. 

• Oversleeping

However, 8 hours is not a rigid number. Your sleep cycle can extend up to 12 hours depending upon the level of rest your body requires. However, a sleep cycle of 12 hours should not become the norm as it can have side effects. It is best to limit your sleep cycles between 8-10 hours. 

• Lack of Sleep

On the other hand, lack of sleep has consequences as well. If your work or life requires you to stay awake past your bedtime for a couple of days, you will be fine. However, you will not be fine if your body constantly suffers from a lack of sleep. 

Consistent lack of sleep can manifest itself as multiple neurological and systemic problems. So, it is best not to have only a 5-hour sleep schedule every night. It is optimum to sleep at least 8 hours.

Stages of Sleep

Despite your routine, whether you sleep more than eight hours a night or less than eight hours a night, your body goes through different stages of sleep. These stages of sleep progress at an optimum rate if you obtain a full eight hours night sleep and will be disrupted with you obtain less or more hours of sleep. 

The stages of sleep are divided into REM sleep or non-REM sleep. Non-REM sleep is further divided into three stages. 

• Non-REM Sleep

In the first stage, your eye movements start to decline and your heart rate goes down. In the next stage, your eye movements are close to zero, your heart rate is at the lowest optimum stage, and your neurons start firing at a slower pace. 

In the third stage, your eye movements stop completely, your heart rate is minimal but normal, your breathing rate is at the lower end, your neurons fire at the slowest pace, and your muscles completely relax. 

The deep sleep that you all might have heard about happens in the third stage of non-REM sleep. During this deep sleep, it is very difficult to wake up. However, if you wake up during a deep sleep, you will feel groggy and irritated. 

The non-REM sleep cycle lasts for 90 minutes. The REM to non-REM sleep cycle is a continuous cycle as it keeps repeating itself until you wake up. After passing through these three stages of non-REM sleep your body progresses to REM sleep. 

• REM Sleep

During REM sleep your eye movements become rapid, your heartbeat goes up, and your neurons fire at a higher pace. It has been concluded in many studies that dream only occur during REM sleep. The REM sleep lasts for about 10 minutes and then the cycle resets as you start from stage one of non-REM sleep.

REM Sleep

Rapid eye movement or more commonly known as REM is the last stage of the sleep cycle. During this stage, as the name suggests, the eyes move in every direction at a rapid pace. However, it does not send any visual signal to the occipital lobe (visual centre) of the brain. 

Moreover, the brain becomes more active and starts firing neurons at a higher pace. Certain parts of the brain, such as those responsible for learning, retaining memory, producing human growth hormone, and formulating amino acids for protein build up are stimulated during REM sleep. 

Furthermore, the heart rate and breathing rate fasten during REM sleep. However, this does not mean that you are up. The increased stimulation of the brain and a higher heart/breathing rate increases the propensity of individuals to have vivid dreams. 

The REM sleep cycle lasts for 10 minutes during the first sleep cycle. It continuously gets longer with each passing cycle. Some researchers reported that the REM sleep cycle can last even more than an hour up till the end of the sleep cycle. 

Another major feature of REM sleep to note is that all the muscles of the body practically become paralyzed during this sleep stage. Since the brain is hyperactive and dreaming vividly, this feature stops the human body from physically acting out those dreams. 

However, your ability to achieve REM and time spent in it varies with age. Children can spend about 50 percent of their sleep cycle in REM sleep. On the other hand, adults usually only achieve REM sleep 20 percent of the total sleep cycle. 

At the other extreme end, older individuals might not even achieve REM at all. Many factors play a role in time duration and the ability to achieve REM sleep with age. 

Benefits of REM Sleep

It must be evident till now that REM sleep is quite an important stage of the sleep cycle. We are here to discuss specific benefits associated with REM sleep. 

• First of all, the production of human growth hormone increases during REM sleep. This is the reason why babies and adolescents have a higher percentage of REM sleep achieved per night as opposed to adults. 
• During REM sleep, your brain explores all the data you have collected throughout the day including emotions and tends to sort it out in short term memory and long-term memory. Thus, reduced REM sleep can mess with your memory. 
• REM sleep helps in keeping some complex and important neural pathways alive and fit. It prevents neural degeneration. Thus, a night of lower REM sleep in old age results in mental problems. 
• REM sleep also decreases inflammation and pain perception. So, during recovery from an injury, REM sleep helps the cells to regenerate faster while reducing inflammation and reducing pain perception. 
• Since your body becomes active in REM sleep as opposed to the state in Non-REM sleep, the blood supply to certain organs increases providing them nutrients to nourish themselves. This leads to healthier organs. 

These are just some of the benefits associated with REM sleep. The scientific community is still looking into the benefits and factors associated with REM sleep. The research to date indicates that REM sleep is a very important and beneficial part of the sleep cycle. Therefore, we should do everything in our power to achieve a healthy amount of REM sleep every night. 

Factors influencing REM Sleep

There are many factors implicated in influencing and decreasing REM sleep. Most of these are in our control and the others can be controlled with the help of supplements. 

• Dietary habits
• Lifestyle
• Exercise 
• Sleep routine 
• Hormonal balance 
• Health status
• Comorbidities 

Supplements that Support REM Sleep

The main hormone implicated in the sleep cycle is melatonin. Therefore, supplements containing melatonin increase the effectiveness of falling asleep. When the sleep cycle normalizes, all the stages of sleep are effectively achieved. 

Thus, normal or increased melatonin concentration in the body can be linked to the higher efficacy of REM sleep. This is the major reason melatonin containing supplements are often prescribed for individuals that have a disturbed sleep cycle. 

You can choose from either those supplements that directly contain melatonin or those that stimulate the production of endogenous melatonin. Other ingredients that are linked with a better sleep cycle and REM sleep include herbs that have a sedative and calming effect. 

A stressful lifestyle can have a devastating effect on our sleep cycle. Thus, calming and sedative herbs can be taken to induce sleep. As we all know, stress lowers hormones and creates reactive oxygen species that cause the body to stay in constant fight mode. 

Herbs such as chamomile extract, passionflower herb, and lemon balm leaf are known to have sedative and calming action. Thus, these ingredients are often found in the ingredient list of sleep-enhancing supplements. 

Furthermore, you only fall asleep when your body is fully relaxed. Thus, those supplements that induce relaxation of muscles and the brain can also be linked with better sleep cycles. CBD is very effective in inducing body-wide relaxation. 

So, CBD associated supplements can also be used to enhance your sleep cycle. Lastly, a few amino acids such as L-theanine and hydroxytryptophan are directly linked to the production of certain neurotransmitters. 

The neurotransmitter balance is key to maintaining healthy brain function. A healthy brain is directly related to a better sleep cycle. Thus, supplements with a healthy amount of amino acids and minerals can be used for the enhancement of the sleep cycle. 

Issues Associated with Irregular Sleep cycle

Normal circadian rhythms should not be taken for granted. The sleep-wake cycle balance allows our body to function properly. Even a slight distortion in this cycle can have devastating effects, if not remedied as soon as possible. 

We have already explained the importance of REM sleep in detail. Now let’s discuss what happens when you do not get enough REM sleep for a long time. We are not saying that these issues start to occur the minute you stop experiencing REM sleep. 

Rather, these issues occur when you go a long time without experiencing REM sleep. 

• Heightened pain perception 
• Reduce memory retention 
• Foul mood (grogginess, increased irritability)
• No vivid dreams 
• Reduction in Human growth hormone production

These are the superficial effects that humans naturally experience due to loss of REM sleep. Medical issues only start to occur when the patient becomes incapable of achieving REM sleep for a long time.