We have all heard about “Blue Light”, “blue light filters” and “digital strain”, but what do these terms mean? How do you explain these buzzwords to your patients without getting into technical language that they can’t relate to? Here are some easy ways to relay the information.

What is blue light?
Visible and invisible light rays are types of rays that the eye can and cannot see, respectively. Both have a range of colors and effects on the eyes that are different in outdoor and indoor environments. On the visible light spectrum that can been seen by eyes, “Blue light” is a color with short wavelengths that produces high amounts of energy.i It is more commonly known as High Energy Visible (HEV) blue light.

What are the sources of HEV blue light?
The main source of naturally occurring blue light comes from the sun. Being outdoors under the sun is where the most exposure to blue light comes from. Man-made blue light for indoor uses comes from fluorescent and LED lighting, flat-screen televisions and display screens of computers, tablets, smartphones and other digital devices.

How is blue light harmful to the eyes?
HEV light has been identified as the most harmful light for the retina. This is because the eye is not very good at blocking out blue light.ii The ocular lens absorbs short-wavelength light which allows the blue light to reach the retina. Children are at a higher risk for this type of retinal damage as their lens absorbs the blue light more than an adult’s lens. iii
What are the benefits of HEV blue light?
Blue light is essential for good health in many ways. HEV light helps with circadian rhythm, which is the body’s natural awake and sleep cycle. When the body is exposed to blue light during the daytime it helps to maintain a healthy circadian rhythm or cycle. Blue light also increases alertness, helps with memory and cognitive function and elevates mood. A significant amount of blue light is used in light therapy to treat seasonal affective disorder (SAD), a type of depression that’s effected by the changing seasons.iv It also makes the sky look blue!
What are the dangers of blue light?

As we become more dependent on all our digital devices, our eyes are excessively exposed to man-made blue light at an extremely close range. This concerns experts about the possible long-term effects. Side effects of blue light include digital eye strain, nearsightness (mytopia), eye fatigue, headaches, dry, itchy, irritated eyes and loss of focus flexibility. Excess blue light exposure at night such as watching TV, playing video games or using the computer, tablet or smartphone will cause sleepness nights and fatigue during the day.
Prevention Tips:

Prevention is the best medicine. Here are some realistic ways to safeguard your eye health without giving up your devices. Start by adding a daily time limit spent on all screens. Encourage spending time outdoors, create “screen-free” areas such as the car, dinner table and at restaurants. Take frequent eye breaks from screens by applying the 20-20-20 rule; after 20 minutes of screen time, look away for 20 seconds and focus on something else at least 20 feet away.v If you are continuously exposed to screens for most of the day, it may be wise to invest in a pair of glasses that have a special blue light filter on the lenses. It will provide better comfort for your eyes and less fatigue. Lastly, adjust your screens settings under “display color filters” to help reduce the blue light emitted from your devices.
Use this back to school season to help educate parents on the effects of HEV blue light rays with the information above. This will help create a seamless additional sales opportunity by emphasizing the importance to your patients the need to purchasing blue light filtering lenses or glasses. Especially for their children who are more susceptible to the harmful rays.
http://www.bluelightexposed.com/#blue-light-and-macular-degeneration
https://www.aoa.org/Documents/OptometryCares/Blue%20Light%20Impact%20in%20Children.pdf
https://www.allaboutvision.com/en-ca/digital-eye-strain/blue-light/
https://www.chop.edu/news/health-tip/how-too-much-screen-time-affects-kids-eyes