It is Monday, 8:15 a.m. A teenager is sitting in the first lesson of the day and can barely keep their eyes open. The teacher thinks: 鈥淭hey were on their phone until late again.鈥� Their parents are convinced they are lazy. In reality, however, the problem very often lies elsewhere: in biology.
That is precisely why I have been studying sleep for several years now. As a psychologist, researcher and clinician. One question interests me more than any other: why do so many people sleep poorly, even though they very much want to sleep well
鈥� says Dr Klaudia Taba艂a.
When we think about sleep, we usually focus on how long we slept and whether we slept well. Less often do we pay attention to when we sleep. Yet sleep regularity and alignment with our chronotype are just as important as sleep duration. Chronotypes really do exist. They are not a trend or an excuse, but an element of our biology. They are influenced by genetics and change with age. Children are more often larks, while during adolescence many people shift towards being 鈥渙wls鈥�. Then, in later adulthood, we become more morning-oriented again. Why do teenagers not fall asleep early? It is not simply a matter of bad habits or a lack of discipline. During adolescence, the biology of sleep changes. Evening sleepiness appears later than it does in children and adults because the body begins producing melatonin, the hormone that facilitates sleep, at a later time. This is why many teenagers genuinely find it difficult to fall asleep at 9 p.m. or 10 p.m., even if they try very hard.
This does not mean, of course, that evening habits are unimportant. Using social media, gaming or doing homework late into the evening can further delay sleep onset. A growing body of research also shows that it is not only the screen itself that matters, but what we do on it. Watching a calm film has a very different effect from emotionally engaging scrolling through social media. These factors, however, overlap with the natural biological delay in the sleep rhythm (Bauducco et al. 2024).
Social Jet Lag
The problem is that teenage biology collides with reality. School begins at a set time, buses do not wait, and a teenager鈥檚 body would happily sleep for another hour or two. School requirements, daily responsibilities and commuting force teenagers to wake up much earlier than would be natural for them (Crowley et al. 2007; Carskadon et al. 2004). The result? Teenagers are sleepy from the very start of the day, yet in the evening they still find it difficult to fall asleep at a 鈥渞easonable鈥� hour as expected by their parents. This often leads to unnecessary conflicts. Trying to force oneself to fall asleep does not help and may even contribute to the development of insomnia. And there is something else. Going to bed like an owl and getting up like a lark leads to sleep deprivation. The deficit grows from Monday to Friday, and then comes the weekend catch-up sleep. The sleep debt is reduced somewhat, but another phenomenon appears: social jet lag. In other words, it is a change in time zones without travelling anywhere. If we wake up four or five hours later at the weekend, it is as if we had flown to India for two days. It is hardly surprising that returning to the school routine on Monday is so difficult. The body may need several days to synchronise again, and just as that happens... another weekend comes.
(...) Nearly 70% of participants reported feeling sleepy during lessons
鈥� says Dr Klaudia Taba艂a.
So, how can we cope with all this and become more alert in the morning? Drinking coffee until the evening certainly will not help, because it will further reduce sleep quality. Morning physical activity, on the other hand, can be beneficial, as can exposure to bright light. Light, ideally natural light, from the beginning of the day helps us wake up and keeps our circadian rhythm on track. Interestingly, a growing number of studies suggest that an adequate dose of daylight throughout the day may reduce the body鈥檚 sensitivity to evening light, for example that emitted by screens (Tavella et al., 2026).
Together with colleagues from three other Polish universities, we conducted a pilot study on the sleep habits of Polish students aged 18鈥�19. On average, they slept around 6.5 hours on weekdays and approximately 9 hours at weekends, demonstrating the extent of the sleep deficit they try to compensate for. Nearly 70% of participants experienced sleepiness during lessons, while almost half reported poor sleep quality. We plan to expand the research to a larger sample in order to make it more representative. Even so, these pilot findings closely reflect the sleep situation of teenagers around the world.
Teenagers worldwide do not get enough sleep, and educational systems are not adapted to their biology. An adolescent brain combined with poor sleep is a particularly explosive mix. A sleep-deprived teenager has greater difficulty concentrating and regulating emotions, is more impulsive, engages more frequently in risky behaviours and achieves poorer academic results (Tamura et al. 2022).
How Can We Help Our Body Wake Up?
We should therefore work to destigmatise teenagers鈥� sleep patterns and considering systemic changes. In places where school start times have been delayed, students slept longer, were less likely to fall asleep during lessons, attendance improved and even the number of road accidents involving young drivers decreased. It turned out that a relatively small organisational change within schools could bring surprisingly broad benefits (Barlaan et al., 2022; Borisenkov et al., 2022; Bowers & Moyer, 2017; Chan et al., 2024; Meltzer et al., 2022).
Sleep as a Component of Health
Sleep interests me not only as a researcher. In my daily work, I also support people suffering from chronic insomnia. This is not simply the occasional poor night鈥檚 sleep. It is a disorder in which difficulties falling asleep or maintaining sleep persist for at least three months and begin to affect everyday functioning. The most effective treatment method is cognitive behavioural therapy for insomnia. It is safer and produces more lasting effects than pharmacotherapy. One of its major advantages is that it provides patients with knowledge about sleep and teaches them what to do should insomnia begin to get more intense.
As part of interviews I conducted with psychologists working with people affected by insomnia, I asked what therapeutic outcomes they observed that were not directly related to the parameters typically measured during treatment, such as sleep duration or sleep efficiency. It turned out that people鈥檚 relationship with sleep becomes more balanced. They stop trying so hard to fall asleep, and their attention gradually shifts away from thoughts about sleep and the bed towards what is happening during the day. They report better emotional regulation, more time for themselves and even greater enjoyment of their relationships with loved ones. They also describe beginning to exercise, and doing so for pleasure rather than simply to sleep better.
It is in moments like these that the true value of research becomes most visible: when knowledge about sleep helps improve the organisation of schools, enables more effective treatment of insomnia and other sleep disorders, and changes the way we understand people鈥檚 everyday difficulties. The longer I work in the field of sleep, the more convinced I become that good sleep is rarely a matter of willpower. Far more often, it requires understanding one鈥檚 own biology, psychology and daily habits. If this understanding helps a teenager stop being perceived as lazy, or enables a person with insomnia to stop blaming themselves for another sleepless night, it will be the best possible evidence that science genuinely changes everyday life.
Photos: Dr Bartosz Ka艂u偶ny, Centre for External Relations and Social Responsibility of the University, 91桃色
Source: Dr Klaudia Taba艂a, Faculty of Educational sciences, 91桃色
Edit: Dominik Nogala, Centre for External Relations and Social Responsibility of the University, 91桃色
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