How does using electronic devices affect sleep?

The human biological clock is controlled by a 24-hour day-night rhythm. Every morning when sunlight appears, the body begins to produce cortisol - a hormone that helps you stay awake, alert, and ready to start a new day. In the evening, when natural light decreases, the body increases the secretion of melatonin - a hormone that makes you feel sleepy. This is the basic mechanism that helps us maintain regular sleep habits.

However, in the modern world, light from electronic devices has significantly disrupted this biological mechanism. Smartphones, tablets, laptops, televisions and even familiar LED light bulbs all emit short-wavelength light, commonly known as blue light. Blue light not only tricks the brain into thinking it is still daytime, but also directly inhibits the production of melatonin, pushing back the feeling of sleepiness.

Many studies have shown that blue light has the strongest impact on the biological clock when exposed in the evening. Not only does it make the body "less sleepy", blue light also reduces the duration of two important sleep stages, deep sleep and REM sleep - stages closely related to memory, emotion and brain recovery. When these two stages are narrowed, even if you sleep enough hours, the quality of sleep is still significantly reduced.

Electronic devices and common sleep problems

When you use a screen device before bed, your eyes and brain receive continuous blue light signals. This makes it take longer to fall asleep. Instead of falling asleep in a few minutes, you may lose 30-60 minutes just by scrolling through Facebook or watching a video.

In children and adolescents, the impact is even more serious. Many studies show that children who use electronic devices at night often have shorter sleep duration, restless sleep, light sleep, and wake up easily, and especially feel tired and less focused the next day.

This is because young brains are more sensitive to bright light and strong visual stimuli. In addition, exposure to stimulating content such as games, entertaining videos, or social media also contributes to making it difficult for the brain to “turn off” in preparation for sleep.

One factor that often goes unnoticed is artificial lighting in the home. One study found that bright bedroom lighting can reduce or delay melatonin production by up to 90 minutes compared to dim lighting. This means that even if you don’t have your phone in your hand, the light from white LEDs or fluorescents can still make it difficult to fall asleep.

Unlike blue light, red, yellow and orange light have little effect on the biological clock. Therefore, experts recommend that if you need to turn on the light to read or relax before bed, you should choose a dim, warm light.

Useful tips for using technology devices at night

While it’s ideal to avoid screens for at least 1-2 hours before bed, this isn’t always possible, especially if you work at night or rely on your phone for entertainment. However, there are strategies you can use to minimize the negative effects:

1. Reduce screen time throughout the day

Many people focus on limiting screen time at night, but excessive daytime screen time can also disrupt circadian rhythms. In adolescents, prolonged device use has been linked to a number of effects, including inadequate sleep, difficulty falling asleep, and increased risk of chronic sleep deprivation.

Therefore, parents should talk to their children about screen time and set appropriate limits, such as no phone use after 9 p.m. or no device use during meals.

2. Build a relaxing habit before bed

A consistent nightly routine will help your body recognize when it’s time to wind down. In the hour before bed, prioritize relaxing activities like reading a physical book, listening to soft music, meditating or doing breathing exercises, taking a warm bath, and journaling. It’s important to avoid screen devices altogether during this time.

3. Remove screens from the bedroom

Many people keep a TV in their bedroom for entertainment, but it disrupts sleep more than you might think. Not only is the light from the screen harmful, but noise or overly engaging content can also make it difficult for the brain to relax.

Therefore, the best choice is not to put a TV in the bedroom, do not use the phone in bed and put it on silent mode or leave the phone outside the room. This habit also applies to children to form a standard sleeping environment early.

4. Keep the bedroom lighting dim

To help you fall asleep quickly, you should use a yellow or red night light, turn off unnecessary light sources and use curtains if there is strong light from outside. The dimmer the light, the easier it is for the body to enter a natural state of sleep.

5. Use “Night Mode” on your device

Most devices now have blue light reduction modes, such as Night Shift on iPhone or Night Mode on Android. However, not all modes are effective if the screen brightness is still high.

Therefore, the best advice is to keep night mode on all evening, reduce brightness to the lowest possible level and avoid watching highly stimulating content.

6. Use blue light blocking glasses

If you must work at night, blue-blocking glasses are a good solution. Orange-tinted glasses filter out most of the blue light, making melatonin production less disrupted. They’re inexpensive—many models cost under $100—and have been shown to be effective in numerous sleep studies.

While it may be tempting to use your computer or phone before bed, studies have shown that these devices can interfere with sleep by suppressing the production of melatonin, a natural hormone released in the evening that helps you feel tired and ready for sleep. This leads to neurophysiological stimulation that increases feelings of alertness./.