Restful sleep: what do the scientists say?

Did you know that without restful sleep you cannot retain information related to school, work, friends or important events because the brain cannot consolidate memories? Well, since we sleep for about 26 years of our lives, and the quality of our sleep can influence our mental health, it is important to understand this phenomenon as well as possible.

In addition to the impact on memory and concentration, almost every type of tissue and system in the body can be affected by lack of sleep - from the brain, heart and lungs to metabolism, immune function and resistance to disease. Research shows that a chronic lack of sleep, or poor quality sleep, increases the risk of disorders including diabetes, high blood pressure, cardiovascular disease, depression and obesity.

In this article, we'll discuss how many hours of sleep you need, sleep cycles, and how you can combat rest problems so you can enjoy life to the fullest.

why are you sleeping

When you sleep, the body "shuts down" and most of its systems become less active. The main processes that take place in the body are:

• Energy conservation and storage . Throughout the day, cells throughout the body use accumulated resources to perform their functions. During sleep, the body's energy consumption decreases, allowing these cells to recharge for the next day.
• Self-repair and recovery . By being less active, the body can more easily heal from injuries and repair problems that occurred during the day. That's why more hours of rest are needed when you're sick.
• Maintaining brain health. During sleep, the brain reorganizes and catalogs memories and learned information. This is similar to the work of a clerk sorting through documents in an archive, keeping what is important and discarding what is unnecessary.

How much sleep do you need?

Although the hours of sleep people need can vary depending on genetic, personal, illness, pregnancy or other reasons, the following schedule is recommended:

• Newborns (up to 3 months): 14 - 17 hours;
• Infants (4 months to 12 months): 12 - 16 hours;
• Small children (from 1 to 5 years). 10 - 14 hours;
• School-age children (between 6 and 12 years): 9 - 12 hours;
• Teenagers (aged 13 to 18): 8 - 10 hours;
• Adults (18 and over): 7 - 9 hours.

Sleep cycles

Brain activity has predictable patterns, which experts divide into two categories: rapid eye movement (REM) sleep and non-REM (NREM) sleep.

When you fall asleep, you usually enter NREM stage 1, followed by NREM stages 2 and 3. After that, you enter REM sleep and start dreaming. After the first REM cycle, a new sleep cycle begins in which these stages repeat.

One cycle normally lasts 90 to 120 minutes before another begins, and most people go through four or five cycles a night (assuming they get a full 8 hours of sleep).

Why do you need REM sleep?

REM sleep is a stage of sleep characterized by rapid eye movements, increased brain activity, and vivid dreams. Each REM cycle is longer as the night progresses, and during it the body is temporarily paralyzed except for essential functions such as breathing and eye movement.

Recent research, such as that by neuroscience professor Matthew P. Walke r, has discovered the critical role that REM sleep plays in memory consolidation and emotional regulation. Studies have shown that REM sleep is crucial for processing and storing information acquired during the day, leading to improved learning and cognitive function. In addition, REM sleep is thought to play a role in emotional processing, helping people regulate their responses to stress and trauma.

What to do if you don't sleep

Poor quality sleep and insomnia (characterized by difficulty falling asleep and staying asleep) affect millions of people around the world. Fortunately, several techniques have been shown to help alleviate insomnia symptoms and achieve restful sleep:

• Establishing a regular sleep schedule. This helps regulate your body's internal clock, making it easier to fall asleep and wake up at the same time each day. Avoid sleeping too much on weekends or during the day, as this can disrupt your sleep-wake cycle.
• Creating a relaxing bedtime routine. Relaxing activities can signal the body that it is time for sleep. These can include reading a book, a warm shower, deep breathing exercises, acupuncture, or guided meditation (there are free apps and YouTube videos for this). However, avoid using screens for long periods of time, as the blue light emitted by these devices can disrupt the production of melatonin, a hormone that regulates sleep.
• Creating a comfortable sleeping environment. Make sure your bedroom is cool, dark and quiet. Invest in a comfortable mattress and pillows that provide adequate support for the body. Consider using white noise machines or earplugs to block out any disturbing sounds.
• Limiting stimulants . Avoid consuming caffeine, nicotine, or alcohol close to bedtime, as these substances can interfere with sleep.
• Regular physical activity. At least 30 minutes of exercise a day, done at least five hours before bed, can reduce the risk of excessive weight gain, which in turn leads to the avoidance of problems such as obstructive sleep apnea .
• Regular meals . Eat on a regular schedule and avoid late dinners.
• Low fluid intake before sleep. Try to drink as few liquids as possible two hours before bed to avoid waking up to go to the bathroom.
• Avoiding over-the-counter or prescription drugs that can disrupt sleep. We are talking about some cold and allergy medicines here, the advice is to talk to your GP if you notice a link between these and lack of sleep.

Sources:

https://www.ninds.nih.gov/health-information/public-education/brain-basics/brain-basics-understanding-sleep

https://my.clevelandclinic.org/health/body/12148-sleep-basics

https://pubmed.ncbi.nlm.nih.gov/19338508/

https://www.nhlbi.nih.gov/health/insomnia#:~:text=Insomnia%20is%20a%20common%20sleep,feel%20sleepy%20during%20the%20day .