Researchers talked about the dangers of using a phone before bedtime

It is important for teenagers to get enough sleep, but the habit of using a smartphone late at night can prevent them from falling asleep on time and getting a good night's rest. Even if you need your phone to chat or watch videos, screen time can imperceptibly delay bedtime and make it more intermittent. About how evening smartphone use is related to teenagers' sleep, see the Izvestia article.

After ten o'clock in the evening

Smartphone use in the late evening is associated with falling asleep later, shorter sleep duration, and more frequent nighttime awakenings in adolescents. These conclusions were reached by the authors of a study published in the journal JAMA Pediatrics.

The researchers analyzed data from 425 children and adolescents, whose average age was almost 15 years. In total, they collected information about almost 7.6 thousand nights of sleep. Scientists compared how teenagers slept on those nights when they used smartphones after 22:00 more than usual for themselves, and on those when evening phone use was less prolonged.

It turned out that on nights with more active smartphone use after 22:00, teenagers slept an average of 20 minutes less, and fell asleep 64 minutes later. They were also more likely to wake up within half an hour of falling asleep. The authors also noted the relationship between the duration of phone use after 22:00 and sleep indicators: each additional minute above the individual average level was associated with a later falling asleep and a shorter rest period.

Why does the phone prevent you from falling asleep

Pediatrician and lead researcher Dimitri Christakis noted that reducing evening smartphone use, especially after 22:00 and just before bedtime, can help improve a teenager's sleep. At the same time, the results show a link between phone use and sleep, rather than proving that the smartphone itself is the only cause of violations.

There is another possible mechanism: digital content supports brain activity at a time when the body needs to gradually move to rest. Conversations, videos, social media, notifications, and light from the screen affect the senses and can keep you awake. Bigman also emphasized the role of light in regulating the sleep-wake cycle: lighting can shift the time when a person is ready to fall asleep.

Experts spoke about the impact of reading from a phone on vision and attention.

What is the danger of intermittent sleep?

Lack of sleep can affect the well-being and daily activities of teenagers. Bigman noted that fragmented sleep—that is, sleep that is repeatedly interrupted—is associated with difficulties in attention and concentration, poor sleep performance, irritability, and increased emotional reactivity.

Separately, the researchers drew attention to the use of the phone just before falling asleep. Even if a teenager doesn't spend the entire evening with a smartphone, using the device 5-15 minutes before he falls asleep was also associated with a higher likelihood of nighttime awakenings. However, these findings do not mean that every teenager who uses a phone before bedtime will necessarily have similar problems. We are talking about the identified patterns that help to better understand which evening habits may be associated with the quality of rest.

The smartphone is not the enemy: scientists have proposed a new look at digital habits

How to replace your smartphone before going to bed

Bigman advises parents not to threaten teenagers by having their phones taken away from them, but to help replace evening use of the device with quieter activities. According to him, reading, music, relaxation exercises and stretching can create a less stimulating environment before bedtime.

The results of the study indicate two periods that are worth paying special attention to: the time after 22:00 and the last minutes before falling asleep. In the first case, prolonged smartphone use was associated with a later bedtime and a reduction in its total duration, and in the second case, it was more likely to wake up at night.

The authors of the study believe that reducing evening screen time may be one of the ways to support healthy sleep among teenagers. However, the study does not establish a universal mode of phone use for all children: habits, daily routine and sleep needs may vary.