Learn how LED light harms your eyes and your sleep cycle, and what you can do to protect your health.
Readership: All, especially those who spend hours every day in front of a smart phone screen or a computer monitor.
I’ve put together the results of a cursory study I made of this topic, including the following photos. It shows that it is possible to reduce the adverse effects on sleep caused by watching TV, smart phone, computer, and iPad use.
The Scientific Evidence
LED lights have taken the world by storm over the past five years, mainly because of their vibrant color spectrum and incredibly low operating costs.
But some new studies are showing that certain wavelengths of light, primarily blue, actually inhibit the body’s natural production of melatonin, which promotes healthy circadian rhythms and sleep habits.
Of note, it seems insidious that FB, Line, Linked In, and many other popular sites have blue themes. It’s no accident. Those sites intentionally chose blue as the background color, knowing that it causes viewers to become more alert, and therefore more likely to spend more time on their site. This might also explain why these sites have grown to be more popular than their competitor sites that do not have a blue theme.
LED lights are real culprits of melatonin suppression!
Other than avoiding the use of monitors and displays altogether, there are basically three ways to protect your health from the hazards of blue light radiation. These include: (1) eye wear, (2) theme colors and brightness, and (3) settings and apps that modify the display.
1. Eye Wear
Amber and orange tinted glasses and filters can reduce the transmission of the harmful shorter wavelengths.
If you spend a lot of time in front of an LED screen, especially after dark, you should seriously consider buying amber tinted work glasses! In addition to protecting your sleep cycle, a prescription pair of amber tinted reading glasses can also reduce optometric strain on your eyes.
Blue light is not the same as UV light, so don’t assume you are safe just because you have a UV coating. One easy way to check if your glasses have a blue light filter coating is to look at the color of the light reflected off the surface of the lens (as shown in the above photo). If the reflected light is white, then the lenses definitely do not have any blue light protective coating. If the reflected light is blue or violet, then the lenses probably have a blue light filter. (If the reflected light is some other color, then it has some other kind of coating. (For example, a scratch protection coating usually has a green reflection.)
Of course, you can only be certain by having an optometrist or an optical laboratory test the optical transmission of the lenses with a spectrophotometer.
2. Theme Colors and Brightness Settings
Changing the background theme color on your smart phone helps too. Choose red, orange, brown, black, dark grey, or amber for best results. Avoid white, blue and purple.
To change the theme color, hold your finger down on the home screen until you get this display. Then touch “Themes”, and select a suitable color.
iOS 9.3 has a “night shift” which turns the screen yellowish to try and reduce the blue-light effect.
If you work long hours on the computer, you may want to experiment with the brightness setting. Try to find the lowest brightness which is still easy to read. Some monitors have “eco” settings, which reduce brightness in order to conserve power usage. There are even some “eco” monitors which are able to automatically adjust the brightness to match the intensity of light present in the room.
3. Apps and Display Settings
There are some free apps available that can filter out short wavelengths of light on smart phones. These should be used within an hour or two before bedtime.
The image, below left, is the control screen for a blue light filter app. Several theme colors are available.
The image, above right, is the same control screen for the blue light filter app, after it is turned on.
Different theme colors are available for many apps. It’s important to know that white light also contains blue light, so in addition to black, grey, or brown, any “hot” colors, such as red, orange, yellow, or pink, are the better choices among themes here.
If you become aware of the effects that blue light from monitors and displays have on your body and health, then you may notice an increase in your dynamic vitality, even after only a few minutes!
To reduce the harmful effects that blue LED light has on your eyes and circadian cycle, consider the following changes.
- Use reading/computer glasses with a blue-light filter coating.
- Change the theme color on your mobile phone*.
- Change the background color on any apps you use*.
- Install a blue-light filter app on your phone.
- Be conscious of the difference between the brightness of your phone, and the ambient brightness of your environment. Adjust the brightness of your phone to a comfortable setting.
- Adjust the brightness of the display monitor on your computer, which reduces the intensity of light.
* Dark or “hot” colors (e.g. red, orange, amber) are more favorable. Avoid white, blue, or purple.
[Eds. note: To avoid confusion, “hot” colors have a cold color temperature (e.g. 2,700K), and “cold” colors have a hot color temperature (e.g. 6,500K).]
Using these methods might seem a little boring at first, but once you get into the habit of using them, you may notice that you feel better. You will experience less eye strain, fewer occasions of headaches, and better sleep rhythms.
This is about as safe as it gets, unless you can put down your phone and go to sleep.
- David Wolfe: 3 Serious Reasons Why You Need To Stop Using Your Cell Phone At Night! (March 22, 2016)