Using a phone in the dark is a bedtime ritual for many people. One message or video after another glides across the screen, killing the short hours before bed. According to data released by the China Sleep Research Society in 2021, 61 percent of Chinese people play with their mobile phones before going to bed.

A sample survey of Japanese young people aged 18 to 30 shows that 96% of them use smartphones at night.

A survey by Villanova University in the United States also found that 90% of young people use their phones to surf the Internet before going to bed, put their phones on their pillow and fall asleep, which has adverse effects on sleep quality and mental health that should be examined closely.

When I look at my phone in the dark, what happens to my eyes?

Turning off the lights for a long time to scroll your phone may make your eyes feel dry.

In a dark environment, the light intensity from a phone is far from enough, so the distance required to see the phone will get shorter and shorter. The eyes focus on the small screen with widened pupils, and with the shortened distance, everything will be blurred. Looking at your phone in the dark for a long time may also induce glaucoma.

In addition, the ciliary muscle of the eye is in a state of tension and fatigue for a long time, which will cause abnormal adjustment function, resulting in myopia or increased myopia, and the damage to the eyes will be more serious.
For the elderly, the lacrimal gland gradually atrophies and ages, becomes prone to dry eye and tear film instability after blinking. These results will aggravate dry eye symptoms, induce acute glaucoma, and also stimulate the fundus macula and crystals, resulting in macular disease and greatly increased risk of cataracts.

It’s not just the eyes that are damaged

Playing mobile phones before going to bed for a long time can cause damage to the body in all aspects, not just visual damage.

Blue light interferes with melatonin secretion

Melatonin is primarily involved in regulating the sleep-wake cycle and circadian rhythm in humans.

Researchers at Harvard University in the United States found that the human body in 1.3 lux (lighting intensity unit) blue light irradiation, melatonin secretion will stop. The intensity of blue light emitted by our commonly used tablet, computer, mobile phone and other light sources is far more than 1.3 lux.

Just two hours before going to bed using an electronic device with a screen can reduce melatonin production by 22 percent, and children and adolescents are more affected by blue light than adults.

The wrong posture hurts the waist and neck

Lying on your side to scroll will create a lot of pressure on the cervical and lumbar spine, leading to numbness, neck stiffness, back pain, dizziness, and spinal diseases.

Developing phone dependence

Many people who love to scroll at night are suffering from “phone dependence.”

This may result in restlessness, difficulty concentrating and other emotional symptoms similar to substance addiction when a phone is not around. Being addicted to your phone can also affect interpersonal relationships and increase loneliness. The desire to get rid of loneliness can lead to greater dependence on phones, creating a vicious cycle.

Wearing the wrong headphones damages your hearing

Many people that look at their phones at night wear headphones in order to not disturb others. High volume and prolonged use can lead to hearing loss, which may be irreversible.

The recommended way to check your phone before bed

If you really can’t help playing mobile phones before going to bed, you can actively adjust the length, brightness, and action of playing mobile phones.

Don’t look at screens in the dark

To ensure the room is bright enough, turn on a bedside lamp. Make sure to keep the distance between the eyes and the phone at least 12 inches, or around 30 centimeters.

Give yourself a time limit

If it is difficult not to use the phone at all before going to bed, limit the length of use to 30 minutes.

Try not to lie on your side or stomach

Put a supportive pillow on your bed. Try to sit upright as opposed to lying on your side or your stomach to scroll on your phone.

Wear headphones to remember the two “60 rules”

Headphones should be used at 60% of the maximum volume and used for no more than 60 minutes. Turn off all electronic devices before going to sleep and place them far away from the bed.

Many people are not aware of the effects of using mobile phones before going to bed, just using it as a way to relax.

Instead of scrolling on your phones before bed, you may want to try chatting with your family, listening to some soothing music or meditating, which are all conducive to better sleep.