Why do we need sleep?
Among Europeans, the French sleep the longest, sleeping nearly 9 hours per night. In a global perspective, they are surpassed only by the Chinese, who sleep a full 9 hours. Poles, on the other hand, rank 9th, devoting on average 8 hours and 28 minutes to sleep. Considering that about 20 percent of Poles do not go to bed without sleeping pills, the results are not optimistic.
Sleep consists of the four phases of NREM sleep and the REM phase that follows, and the cycle itself repeats several times. We need it for proper functioning, body regeneration, growth, and hormone production.
During sleep, memory consolidation occurs, responsible for organizing and remembering information, and neural networks are formed so that we wake up ready to work again in the morning. This is confirmed by a study by researchers at the Ludwig Maximilian University in Munich, which shows that sleep helps to consolidate the individual pieces of information that we have provided to our brain during the day.
We then reinforce our memories and repeat facts that will come in handy the next day*. Insufficient sleep therefore leads to disrupted physiological processes, poorer metabolism, impaired memory and cognitive abilities, and even poor mental health.
Chronotype and age-appropriate amount of sleep
Are you a night owl or an early bird? Do you have more energy to do things when you go to sleep early and get up early, or are you most productive at the end of the day so you prefer to go to bed later and get up later? Contrary to appearances, it’s important to know your sleep chronotype and adjust your circadian rhythm accordingly. Whether you’re closer to an owl or an early bird, getting enough sleep is paramount. According to the National Sleep Foundation, adults aged 18 to 64 should get 7 to 9 hours of sleep, those over 65 should get a maximum of 8 hours, school-aged children should get 9 to 11 hours, and newborns and infants should get 12 to 17 hours of sleep a day. The more research is done on sleep, the more it shows that good sleep is worth taking care of.
Fixed times for falling asleep and waking up
When taking care of your sleep, it’s good to start with the basics, so consistent times of falling asleep and getting out of bed are very important. Irregular bedtimes translate into an irregular circadian rhythm, and catching up on sleep at weekends is a road to nowhere. Neurotherapist Joanna Kamińska mentions this, pointing out that “the body adjusts poorly to changes in sleep hours”**.
Exposure to natural light
Before we entrusted ourselves completely to our clocks, our internal biological clock had informed us about the times to get up and go to sleep, adjusting itself to the sunrise and sunset. And while times have changed, our internal rhythm continues to work the same, which is why exposure to natural light, at least 30 minutes a day, is so important. Contact with sunlight affects the production of melatonin, a hormone produced by the pineal gland that regulates the circadian rhythm.
While sunlight is the best investment into sleep, the body’s exposure to blue light, especially during the later part of the day, will be associated with poorer sleep quality, taking longer to fall asleep, and metabolic problems.
There is a growing body of research on the health effects of artificial light. In 2014, a publication was released describing the results of a multi-year study of more than 100,000 women in the United Kingdom. “Women whose bedroom had brightness that allowed them to read or distinguish objects had a significantly higher risk of being overweight and obese, compared to subjects whose sleeping area was darker.”***
A bedroom conducive to a good night’s sleep
The room in which we sleep is very important for our well-being and the quality of sleep itself. It is recommended that it should be as dark as possible, without any awakening noises, and its temperature should be maintained at 16-20 degrees Celsius. The World Association of Sleep Medicine points out the importance of the choice and use of the bed – it is to be comfortable, cosy and intended for sleep only (not for work or recreation).****
Physical activity and relaxation versus sleep
The quality of sleep is also affected by regular physical activity. However, the time of day we take it is critical, researchers say. Workouts should be scheduled for the first part of the day, as those performed 3 hours before bedtime and beyond can affect autonomic control of the heart during the first few hours of sleep.
Falling asleep is also helped by relaxation. That’s why it’s a good idea to avoid any engaging activities a few hours before bedtime. This is a time for a relaxing bath, reading a book, or doing breathing exercises. The brain needs a clear signal that it can slow down and go into rest mode.
Bad habits that disrupt sleep
Also, do not forget that the hygiene of the day, the time and abundance of meals consumed, as well as stimulants are not irrelevant to the quality of sleep, so:
- Avoid heavy meals and lots of fluids before bedtime.
- Do not reach for nicotine and caffeine found in coffee, tea, coca-cola or energy drinks 8 hours before going to bed.
- Don’t take naps totalling more than 45 minutes and don’t schedule naps after 3 p.m.
- Don’t drink alcohol before bedtime because it blocks falling into the REM phase.
* https://portal.abczdrowie.pl/fascynujace-fakty-na-temat-snu
** http://osrodekcemicus.pl/wp-content/uploads/2014/07/sen.pdf
*** https://terapiabezsennosci.pl/niebieskie-swiatlo-a-sen/
**** https://www.nfs.org.pl/index.php/wiedza/zasady-dobrego-snu/10-przykazan-zdrowego-snu-dla-doroslych/