Does blue light reduce eyesight? The relationship between blue light and eye health

The Truth About Blue Light for Eye Health

There was once a great deal of controversy about the dangers of blue light. The gist of the controversy was that the thalamic cells in the retina were destroyed by blue light, making them more susceptible to macular degeneration and leading to blindness.

However, there has not yet been any study on what happens to people's eyes when they are exposed to blue light. There are only a few animal studies available. Therefore, it is difficult to conclude that blue light causes eye diseases.

According to the American Academy of Ophthalmology, "Smartphone blue light does not blind you." It's not harmful to eye health. This is because the study is an animal experiment, so it cannot be applied equally to humans, the method of light exposure in the study is different from the way light is exposed in daily life, and our eyes have the ability to protect against blue light.

What is blue light?

Blue light is one of the rays emitted by sunlight. It is a blue light that belongs to the low wavelength between 380 and 500 nm. Blue light has the shortest wavelength and strongest energy among visible light. Computers, TVs, and smartphone screens also emit blue light.

Blue light, beneficial light during the day

The blue light emitted by sunlight during the day is very positive. This is because it maintains the circadian rhythm of day and night, which has a positive effect on a good night's sleep. On the contrary, in Northern Europe, where the sun is shorter, blue light is also used as a treatment to stimulate the release of serotonin. Blue light induces the secretion of serotonin, which is called the "hormone of the day," so that even when the sun is short and dark, it is perceived as daytime.

However, it can be devastating at night. This is because exposure to blue light suppresses the secretion of melatonin, a hormone that affects the 24-hour rhythm. The blue light emitted by video equipment, fluorescent lamps, and LED lights disturb the quality of sleep and even the circadian rhythm.

Night lighting is harmful

According to a Harvard study, night lighting increases diabetes and obesity. The researchers gradually shifted the timing of the circadian rhythm to fit 10 people into a schedule. Then their blood sugar levels rose, leading to diabetes, and hormone levels dropped in people after eating.

Harvard sleep researcher Stephen Lockley says, "The light at night is one of the reasons people don't get enough sleep." "Short sleep may be linked to an increased risk of depression as well as diabetes and cardiovascular disease," the researchers say.

How to Deal with Blue Light Healthily

With blue light, you don't have to worry about macular degeneration or blindness. This is because the human eye has a lens and cornea, which are systems that filter out harmful rays, which filter out blue light. However, when it comes to eye health, one thing to watch out for is dryness. This is because when you focus on the screen, the number of blinks decreases to less than 30% of the usual time, which increases the amount of tear evaporation and causes dry eyes.

1. When using electronic devices to prevent dry eyes, it is recommended to rest your eyes by looking at a distant place for about 10 minutes after using them for 50 minutes. If you have to look at the monitor for a long time, you should consciously blink your eyes frequently to relieve dryness.

2. It's a good idea to use dark red lights for night lighting. After dark, it's recommended to block blue light from entering your eyes. Red light has the least power to alter circadian rhythms and suppress melatonin.

3. It's best not to look at electronic devices 2~3 hours before going to bed. This is because blue light can disrupt your sleep rhythm.

4. If you work night shifts at night or need to use a lot of electronic devices at night, it is recommended to wear blue light blocking glasses or install an application that filters blue and green wavelengths at night. Blue light blocking glasses have a coating on the inside of the spectacle lenses to reduce glare caused by blue light reflections and the incident of light entering the eyes.

Of course, glasses that only block blue light are expensive, but cheap orange sunglasses are not suitable for indoor use at night. By exposing yourself to bright light during the day, you can sleep at night and improve your mood and attention during the day.

5. It's a good idea to get plenty of sunlight during the day. By exposing yourself to bright light during the day, you can sleep at night and improve your mood and attention during the day.