Is it true that reading from a screen damages your eyesight?

It is a common belief that reading from a computer, tablet or smartphone worsens vision and leads to myopia. We decided to check whether there is scientific evidence for this point of view.

Parents warn about screen reading being harmful to eyes forums And sites numerous optician. Similar warnings also appear on resourcesdedicated to a healthy lifestyle. The materials claim that reading from a computer or smartphone due to the glowing screen radically reduces vision and causes myopia. IN quality main argument in such articles quotes a 2013 interview with British ophthalmologist David Allamby, in which he statedthat since 1997, the number of patients suffering from myopia who came to his clinic has increased by 35%. He called this phenomenon the special term “screen myopia” and tied up it using smartphones.

First, let's try to figure out how reading from paper and electronic media differs from a physics point of view. As we know from school lessons, a visible object becomes when it reflects or emits elementary particles of light - photons, which fall on the light-sensitive cells of the retina, and from them the signal travels through a chain of neurons to the brain. Photons from the sun or an artificial light source fall on a book sheet, the black letters absorb the photons, and the white spaces reflect them directly onto our retina. From the point of view of physics, it would be more correct to say not so much “I see letters”, but rather “I do not see letters, but I see spaces between them.” In the case of electronic media, we do not need reflected light; the built-in backlight of the screen itself emits the required number of photons so that we can perceive text or an image. 

When there is insufficient lighting, the human eye has the ability to adapt. When we try to see something at dusk, our pupil expandingso that more light reaches the retina. When brighter light returns, the pupil constricts. If the body cannot achieve sufficient brightness, we use external adjustment capabilities: we adjust the lighting to the needs of our vision (turn on brighter light, move closer to the light source), and in the case of electronic media, we adjust the backlight power. It is important to note that the fear that reading in low light will harm your eyesight is absolutely groundless. By tag analogies New York ophthalmologist Richard Rosen said, “It’s like saying that taking photos in poor lighting will damage your camera.”

The largest study of the effects of screen reading on vision can perhaps be called work scientists from Ohio State University. In 1989, they selected 4,512 children aged 6 to 13 years of different ethnic groups without signs of myopia and monitored their vision for 21 years. When developing the study design, among the potential risk factors, scientists identified time spent behind the TV screen, and later on the computer. The study showed that this factor ultimately didn't play significant role in the development of myopia, in contrast to, for example, something that is not obvious at first glance parameterlike outdoor play time. Carla Zadnik, leader of this study, emphasizesthat “although screen time has been considered an important factor in the development of myopia for nearly 100 years, our large and ethnically representative sample did not demonstrate any association.” With Backdrop agree her colleague, Dr. Donald Mutti: “There is no convincing evidence that computer work increases the risk of onset or progression of myopia in adults compared with other forms of work that involve eye strain.”

However, some connection There is a relationship between the amount of time spent reading and the development of myopia. Deterioration of vision due to prolonged work at the monitor is caused by the fact that many do not follow the rules of safe work near, namely, they neglect the necessary distance between the text and the eyes and do not take the necessary breaks to rest the eyes. The most important rule of ophthalmologists called The 20-20-20 rule: Every 20 minutes of work, take a break and look at an object 20 feet away for 20 seconds. By following it, we give our eyes the necessary rest and can continue to work without experiencing unpleasant symptoms or harming our vision. Neglect of this rule most likely explains the “screen myopia” of Dr. David Allamby’s patients.

It is also interesting to note: in 2019, scientists came to the conclusion that reading white letters from a black background stimulates information transmission pathways unusual for our eyes and is a prevention of myopia, in contrast to the standard reading of black letters from a white background. It's also worth mentioning observation Japanese scientists: chewing gum during intense screen reading, using various facial muscles, reduces symptoms of eye fatigue such as dryness, a feeling of sand in the eyes, double vision and pain.

Thus, there is no evidence that reading from a computer screen, tablet or smartphone is more damaging to vision than reading from paper. However, it is important to remember that regardless of whether you have a book in front of you or a mobile phone, you should follow some rules of safe work and, perhaps, following the advice of Japanese scientists, relax your facial muscles while chewing chewing gum while reading.

Not true

What do our verdicts mean?

Read on the topic:

1. Vision as it is
2. 5 myths about myopia