Blue Light: Beyond The Screen

What is Blue Light?

Blue light is part of the visible light spectrum that the human eye can see. Vibrating within the 380 to 500 nanometer range, it has the shortest wavelength and highest energy. About one-third of all visible light is considered blue light. It is found in nature, sunlight being the biggest source of blue light. However, artificial sources of blue light including fluorescent light, LED TVs, computer monitors, smartphones, and tablet screens are where issues spark.

Harms and Benefits

Benefits of blue light is that it boosts alertness, helps memory and brain function, and elevates mood. It regulates your body's natural wake and sleep cycle (circadian rhythm). Sunlight is also important for the growth and development of eyes and vision in children. Harms of blue light can outweigh the benefits. There is concern about long-term effects of screen exposure from digital devices. This is especially true when it comes to too much screen time and screens too close to the eyes. According to the Vision Council, 80% of American adults use digital devices more than two hours per day. Nearly 67% use two or more devices at the same time. 59% have symptoms of digital eye strain. Constant exposure to blue light over time could damage retinal cells and cause vision problems. It can also contribute to cataracts, eye cancer, and growths on the clear covering over the white part of the eye. According to a vision study by the National Eye Institute, children are more at risk than adults because their eyes absorb more blue light from digital devices. 

Blue Light Impact on The Eye

There are many harms from blue light exposure. As we spend hours looking at a computer screen, we don’t blink as frequently (causing eye dryness and discomfort) and our eyes become tense (causing us to have trouble relaxing our eyes).

• Eye Strain and Discomfort- Common indications of blue light sensitivity include eye strain and discomfort after spending extended periods in front of screens.

• Headaches and Migraines- People may also suffer from headaches or migraines, which could be intensified by blue light exposure.

• Insomnia and Sleep Disturbances- Exposure to blue light in the evening can lead to insomnia and sleep disturbances as it interferes with the production of melatonin.

• Blurred Vision and Sensitivity to Glare- Blurred vision and sensitivity to glare are other potential signs that you may be sensitive to this type of light.

How Blue Light Impacts Sleep

Blue light fools the brain into thinking it's daytime. When that happens, the body stops releasing a sleep hormone called melatonin. Melatonin is nature's way of helping us wind down and prepare for bed. The body starts releasing it a couple of hours before bedtime. Darkness helps trigger the release of melatonin; blue light delays it.

Solutions

The one way to fully avoid blue light exposure is to stay off the devices. However, there are ways to limit exposure while on devices.

1.     Wear blue light glasses

2.     Install screen filters on phone

3.     Use low blue light bulbs

4.     Sleep with an eye mask

Sources:

Gary Heiting, OD (english). “How to Decrease Your Child’s Risk of Computer Vision Syndrome.” All About Vision, All About Vision, 27 Feb. 2019, https://www.allaboutvision.com/cvs/children-computer-vision-syndrome.htm

“Does the Light from a Screen Make It Hard to Sleep? (For Teens) | Nemours Kidshealth.” Edited by KidsHealth Medical Experts, KidsHealth, The Nemours Foundation, https://kidshealth.org/en/teens/blue-light.html#:~:text=Blue%20light%20fools%20the%20brain,couple%20of%20hours%20before%20bedtime.