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Sleep Hygiene: Crucial for Optimal Organism Functioning


Sleep hygiene is not just a set of practices, but a true philosophy of caring for our physical and mental health through sleep. In today's increasingly hectic pace of life, we often forget its fundamental importance. Sleep is an integral part of our daily functioning because, while we rest, we also regenerate the body and mind. In reality, sleep is a crucial moment during which the body undergoes a series of highly significant processes, such as cell regeneration, strengthening immunity, tissue repair, and memory consolidation. Therefore, it is worth understanding its significance and exploring practical aspects that can contribute to its improvement.

In today's busy world, we often neglect our needs by cutting back on sleep or ignoring the signals our body sends. That's why proper sleep hygiene is so essential for our overall well-being and health. When considering this topic, it is important to take into account both the physical and psychological aspects of sleep, the environment in which we sleep, our daily habits and lifestyle, as well as individual differences.

REM i NREM: Sleep Stages

Sleep stages, namely NREM (Non-Rapid Eye Movement) and REM (Rapid Eye Movement), play a crucial role in the body and mind's regeneration during sleep. Below you'll find a more detailed explanation of each of these phases:

NREM (Non-Rapid Eye Movement):

NREM Stage 1: This is the initial stage of sleep, characterized by light sleep that can be easily interrupted. During this stage, the brain gradually shuts off from external stimuli, and the body begins to prepare for deep sleep.

NREM Stage 2: In this stage, deeper sleep occurs. Brain activity decreases, and the body enters a state of relaxation. It is the longest stage of sleep, during which the body regenerates and prepares for subsequent stages.

NREM Stage 3: This is deep sleep, sometimes simply referred to as "deep sleep." During this phase, the body undergoes the most repair and tissue regeneration, and the brain processes information gathered during the day. Sleep is most uninterrupted during this phase, and it is difficult to wake a person sleeping at this stage.

REM (Rapid Eye Movement):

This is the stage of sleep characterized by rapid eye movements. During REM (Rapid Eye Movement) sleep, brain activity increases, and sleep becomes more akin to wakefulness. Intense dreams occur during this phase, and the brain processes and consolidates information gathered during the day. REM sleep is also crucial for emotion processing and memory consolidation.

The sleep cycle includes both NREM and REM stages. During a normal sleep cycle, a person goes through several cycles, starting from NREM, transitioning to REM, and then back to NREM. This cycle typically lasts about 90 minutes, repeating several times throughout the night. Each stage of sleep is important for the regeneration of the body and mind, and their proper balance is essential for overall sleep health.

Sleep Disorders:

Sleep dysfunctions can be divided into two categories: dyssomnias, which concern the quantity of sleep, and parasomnias, related to the quality of sleep. Dyssomnias include insomnia, hypersomnia, and circadian rhythm disorders. Insomnia, also known as sleeplessness, is a problem where sleep is perceived as insufficiently long or unsatisfactory. This manifests as difficulties falling asleep, staying asleep, early awakening, or a lack of feeling rested after sleep. Hypersomnia, on the other hand, is a condition where sleep is excessively long or accompanied by a strong feeling of sleepiness. An example of neurologically-based hypersomnia is narcolepsy, characterized by excessive sleepiness and episodes of cataplexy. Circadian rhythm disorders include delayed and advanced sleep phase syndromes, as well as non-24-hour sleep-wake syndrome.

Parasomnias, on the other hand, are abnormal events that occur during sleep, unrelated to either the quantity of sleep or daytime functioning. There are many types of parasomnias, but the most well-known are sleepwalking, commonly known as somnambulism, and night terrors. Sleep disorders are common, especially primary insomnia, which affects approximately 20% of people over the age of 65, more often women. It can be associated with medication, other health problems, or poor sleep habits. Individual behavioral approaches and education on sleep hygiene can significantly improve sleep quality.

What influences sleep disorders? There can be many reasons, ranging from mental health issues to mundane factors such as alcohol, drugs, and caffeine. The impact of such stimulants on sleep is complex and often adverse. They may initially seem to aid falling asleep, but in reality, they disrupt the natural sleep cycle, shortening the REM and NREM deep sleep phases and causing more frequent awakenings during the night. Meanwhile, caffeine, by blocking adenosine receptors, can hinder achieving the necessary state of relaxation for falling asleep. Limiting the consumption of these substances altogether and/or especially in the afternoon and evening can bring benefits for sleep quality and overall well-being.

Impact of Alcohol and Drugs on Sleep:

Alcohol and marijuana, often perceived as aids to falling asleep, can significantly disrupt the natural sleep cycle and lead to serious health problems. Such stimulants, although they may initially seem to facilitate falling asleep, actually lead to sleep cycle instability. They reduce the time spent in the deep sleep stages of REM and NREM, resulting in poorer sleep quality and more frequent awakenings during the night. Moreover, alcohol can exacerbate sleep apnea and other breathing disorders during sleep.

Let's take a closer look at the impact of alcohol and marijuana on neurotransmitters, biochemistry, and hormones, which in turn affect sleep:


1. Neurotransmitters: Alcohol primarily works by increasing the activity of gamma-aminobutyric acid (GABA) - the main inhibitory neurotransmitter in the brain. Alcohol leads to the inhibition of neuronal activity, causing a calming and relaxing effect. However, it can also limit the activity of glutamate, affecting the brain's ability to process stimuli and leading to sleep disturbances.

2. Biochemistry: Alcohol consumption can affect the secretion of various chemicals in the brain, such as serotonin and noradrenaline, which are involved in mood regulation and sleep. Excessive alcohol consumption disrupts the balance of these substances and can lead to sleep disorders, including difficulties falling asleep, reduced sleep quality, and waking up during the night.

3. Hormones: Alcohol consumption can influence the secretion of hormones such as cortisol, which is associated with stress response and circadian rhythm regulation. Excessive alcohol consumption can disturb natural hormonal cycles, leading to sleep difficulties, irregular rhythms, and reduced sleep quality.


1. Neurotransmitters: Marijuana, especially its main psychoactive component, delta-9-tetrahydrocannabinol (THC), primarily affects the endocannabinoid system in the brain. THC activates type 1 cannabinoid receptors (CB1), leading to changes in neurotransmission, mainly by increasing the release of the neurotransmitter anandamide. Anandamide acts as a retrograde neurotransmitter, modulating the activity of other neurons, which can lead to changes in the functioning of the nervous system.

2. Biochemistry: Marijuana appears to alter brain biochemistry by influencing the endocannabinoid system. Increased levels of anandamide may lead to changes in the functioning of various brain areas, affecting sleep. Studies suggest that marijuana affects the secretion of melatonin, the hormone regulating the sleep-wake cycle, which seems to contribute to sleep disturbances.

3. Hormones: There is evidence suggesting that marijuana may affect the secretion of various hormones, including cortisol and melatonin. Some studies indicate the possibility of reducing melatonin secretion, which may simultaneously disrupt the circadian rhythm and sleep regulation. However, the exact mechanisms of marijuana's effects on hormone secretion require further research.

It is worth noting that the impact of marijuana on sleep may vary depending on individual characteristics, dosage, and frequency of consumption. While some people may experience relief from insomnia after consuming marijuana, others may experience worsened sleep quality and other side effects. Therefore, a cautious approach to marijuana consumption and conscious monitoring of its effects on sleep and overall well-being are recommended.

Caffeine and Sleep: A Delicate Balance in Our Bodies

Now, turning to caffeine - a substance that for many of us is a daily ritual. Coffee, tea, energy drinks - they're our support during long days and intense working hours. But have we ever wondered how caffeine affects our sleep?

Caffeine works by blocking adenosine receptors, a substance that helps regulate the sleep-wake cycle. This is a crucial point because adenosine acts as a neurotransmitter that contributes to slowing down neuronal activity, preparing the body for sleep. When caffeine blocks these receptors, achieving the state of relaxation needed for falling asleep becomes more difficult.

The impact of caffeine on sleep may also depend on individual genetic differences. Individuals who metabolize caffeine faster may experience fewer disruptions in sleep than those who metabolize it slower. As a result, caffeine tolerance may vary.

For many people, it's also important to consider the half-life of caffeine. This period ranges from 5 to 12 hours; for some, it may be shorter, for others, longer, meaning that half of the consumed dose will be eliminated from the body within this time frame. Therefore, limiting caffeine intake in the afternoon and evening may be beneficial for sleep quality.

Physical Activity: Key to Health and Harmony

Finally, but no less important, is physical activity. Exercise is not only a way to maintain good physical condition but also a key factor affecting our sleep and overall well-being.

Regular physical activity positively influences sleep by releasing endorphins, which act as natural painkillers and reduce stress. Exercise can also increase serotonin levels, helping to regulate mood. Melatonin, known as the "sleep hormone," is regulated by physical activity.

In summary, regular physical activity can regulate the levels of various hormones, contributing to improved sleep quality, but it's important to adjust the intensity and timing of workouts appropriately. Intensive workouts aren't necessary to reap the benefits of sleep. Even moderate physical activity, such as walking, jogging, yoga, or swimming, can bring positive effects for sleep and overall well-being. However, it's crucial to consider the timing of exercise. Intense exercise before bedtime can increase arousal and make it harder to fall asleep. Therefore, it's recommended to engage in physical activity at least a few hours before the planned bedtime. According to research, intense physical exertion performed late in the evening doesn't negatively impact sleep quality, but it may affect the heart's activity through the autonomic nervous system, especially in the first few hours after falling asleep.

How can we take care of our sleep?

** It is important to establish regular sleep hours. Regardless of the day of the week, it is necessary to wake up at the same time.

** The environment in which we sleep is also of great importance. Reducing exposure to blue light, especially from electronic screens, can help achieve a more peaceful sleep. Therefore, it is worth giving up the use of electronic devices at least an hour before bedtime.

** Dim the lights in the room as much as possible. Consider using an eye mask.

** Investing in earplugs to minimize reactions to external stimuli is also worthwhile. Noise during sleep, such as traffic noise, leads to stimulation of the sympathetic nervous system and the release of adrenaline, noradrenaline, and cortisol. Individual variability and personality are most likely the causes of individual differences in neuroendocrine response. The effects of noise during sleep include poorer sleep quality and fatigue. These effects are attributed to changes in sleep stages, as there is a shortening of deep sleep, lengthening of light sleep, and awakenings.

** Avoiding physical activity and stressful situations before bedtime can also facilitate falling asleep. Instead, it is worth creating a relaxation routine that signals to the body the approaching sleep time. This could include a warm shower, reading a book, or meditation.**

** Diet also affects sleep quality. It is recommended to limit caffeine and alcohol consumption, as well as heavy meals, especially in the evening, as these substances can disrupt the sleep-wake cycle.

** Reduce coffee consumption 12 hours before bedtime and drink less in the evening.

** The temperature in the bedroom also matters. Keeping the room at a moderate temperature ensures more comfortable sleeping conditions. Air out the room regularly to provide fresh air.

** Avoid taking longer naps during the day than 45 minutes to avoid disrupting the sleep cycle.

** Exposure to daylight plays an important role in regulating the sleep-wake cycle in both children and adults.

** Consider investing in essential oils such as lavender, chamomile, or patchouli, which can help relax and calm before sleep.

** When taking care of our sleep, let's not forget about comfort. Choosing the right pillow and duvet can make sleep more rejuvenating.**

** Finally, it is worth creating a bedroom as a sanctuary, solely for sleep and rest. Limiting external stimuli and creating a peaceful, relaxing environment can help achieve better and more restorative sleep.

** As mentioned above, it is recommended to establish a habit to transition from an active state to rest, for example, by engaging in a relaxing activity for 15-30 minutes. Relaxing music can create a perfect atmosphere for immersing oneself in peaceful sleep. Here are a few examples:

Emphasizing Individual Differences:

It is important to understand that each individual may have slightly different sleep cycles and individual needs. These differences may include the time needed for regeneration, preferred hours, environment, and personal preferences. It is important to consider genetic and biological differences that affect the need and ability for regeneration. Some may need more, while others need less time to rest.

Therefore, it is important to listen to our bodies and adjust habits to individual needs. Experimenting with different sleep hygiene strategies and observing how our bodies respond to them can be crucial in finding the optimal sleep plan for oneself.


Taking care of sleep hygiene, controlling caffeine or alcohol intake, and regular physical activity are key elements of a healthy lifestyle. They have a tremendous impact on our well-being, efficiency, and quality of life. By understanding the mechanisms of our body and making conscious decisions about sleep, nutrition, and physical activity, we can introduce positive changes that will benefit us on many levels.

It is worth remembering that every body is different, so it is important to find our own balance and adjust healthy lifestyle practices to our individual needs. Regularity, moderation, and awareness are the keys to achieving harmony between body and mind and ensuring long-term well-being. Therefore, we encourage making conscious choices and taking care of ourselves every day. Remember that sleep is not just a time for rest, but also an investment in our health and happiness.

More Information:


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