In this article by the American Academy of Opthalmology, they are claiming that the reason our eyes hurt when looking at a screen isn’t because of the blue light, but because of the fact that most people blink less when looking at a screen, causing digital eye strain. They recommend using techniques such as the “20-20-20” rule which means “shift your eyes to look at an object at least 20 feet away for at least 20 seconds”, and using eyedrops to lubricate the eyes. They also claim that blue light glasses have zero effect on protecting the eyes.
An article from UC Davis by Melissa Barnett:
https://health.ucdavis.edu/blog/cultivating-health/blue-light-effects-on-your-eyes-sleep-and-health/2022/08
“Since our eyes are not good at blocking blue light, nearly all visible blue light passes through the front of the eye (cornea and lens). It then reaches the retina, the cells that convert light for the brain to process into images.” 80% of Americans use digital devices for two hours or more a day, and 51% experience symptoms of digital eye strain (The Vision Council). Uninterrupted blue light exposure can damage retinal cells and cause vision problems, as well as cataracts and eye cancer.
From PubMed Central:
https://pmc.ncbi.nlm.nih.gov/articles/PMC6288536/
“In the visible spectrum, short-wave blue light with wavelength between 415 nm and 455 nm is closely related to eye light damage”. They claim this damage can cause irreversible photochemical retinal damage.
Blue lights are proven to trigger inflammation of human corneal epithelial cells and can result in oxidation. “The oxidative damage caused by blue light was shown to be reduced by effective antioxidant extract associated-free radical elimination, thus improving the clinical symptoms of the eye surface in a dry eye mouse model[5]–[6] and further confirmed that blue light is associated with the formation of dry eye.” Blue light irradiation can impede on corneal stromal cell activity, which gets worse the brighter the light is and the longer one looks at it.
Both of these articles also mention how blue light has direct effects on the circadian rhythm of sleep. Most people’s circadian rhythm is just over 24 hours, and because the sun is the biggest distributor of blue light, we associate this light with being awake. Looking at screens can stimulate this association and throw off the circadian rhythm of sleep. For example, if someone is looking at a screen even within two or three hours of going to bed, their body will react to the blue light and think it is daytime, causing the person to no longer be sleepy, thus resulting in getting less sleep in general, or sleeping in and causing a decreased exposure to the sunlight throughout the day.