For most of us, our daily lives revolve around our screened devices. We are constantly staring at our phones, laptops, computer and television screens without really thinking about the real problems they could be causing us, especially our eyes.
Recent studies have shown that blue light (also known as high energy visible or blue-violet light) is a form of light emitted from these devices which can be harmful to our eyes and our overall sleeping patterns. This form of light is the reason why our phones and other screened devices appear to look so crisp and clear. Blue light can be harmful to our eye health as it is very close in wavelength to ultraviolet light which is a well- known hazard if we are repeatedly exposed to it.
It has been found that blue light can cause the death of retinal cells, contribute to the formation of cataracts and accelerate retinal damage in those who have macular degeneration. The cause of this is still being studied, however it is thought that the blue violet light disrupts cellular metabolism in the pigment epithelium layer. This contains melanin granules which absorb and attract the energy found in shorter wavelengths like blue light.
Natural blue light such as the blue of the sky also helps with our sleeping patterns as our bodies are able to determine the change of night to day. The light emitted from a phone screen is a form of artificial blue light. When looking at a phone or laptop before going to bed, often the blue light from our screens can confuse our bodies into thinking that it is actually day time and supress the making of melatonin.
While blue light can be damaging to our eyes, it can also be very beneficial to us as it can help regulate our sleeping patterns because its presence supresses the production of melatonin.
Melatonin is the hormone that makes us drowsy and ready for sleep. In the absence of blue light specialised cells within the body known as ipRCGs become switched on. When these cells are activated they connect with the brain and begin the production of melatonin. If melatonin is produced at a certain time on a regular basis then our circadian rhythm and sleep cycles become set.
Some studies have stated that the constant disruption to a person’s melatonin levels can depress the immune system, putting the individual at a higher risk of type 2 diabetes, heart disease and cancer.
Although blue light can be harmful to our eyesight and health, it is impossible for us especially in such a technologically driven society to stay away from it. However, precautions can be taken to lower the risk of exposure such as looking at screens from a safe distance, keeping LED and light efficient bulbs out of bedrooms and bathrooms and lowering the amount of time spent using screened devices.