Here at Provide Your Own, we are a big fan of LED lighting. Recent research has raised the alarm that LED lighting can cause retina damage. Is there any truth to this assertion? Can LEDs really be bad for your eyes, even causing blindness?
Fortunately for LED lovers, the answer is a resounding NO. When the facts are examined, if LEDs are bad for your eyes, then sunlight is at least ten times worse. Let’s first look at the basis for the assertion.
The Research Study
According to a sole news account:
The study found that LED radiation caused significant damage to human retinal pigment epithelial cells in vitro.
We irradiated naked retinal cells with intense light from LEDs in a petri dish and they didn’t do so well.
Keep in mind that damage would be done with any high intensity light. Have you stared into the sun lately? How about staring into lasers or high intensity LED flashlights? Think you might have some retina damage?
This research has not been peer reviewed, but is simply an account given by Dr Celia Sánchez Ramos. This fact does not invalid the research, but shows that we have absolutely no real facts – just a lot of conjecture and opinion. What kind of LEDs were used? How bright was the light? What would be the equivalent damage from sunlight?
The Basis for Concern
Dr. Ramos indicated the blue light inherent in white LEDs was responsible for the damage. Also, of similar concern are CFLs (compact flourescents) which have some light in the blue band. In comparison, incadescents have no blue light whatsover and are heavily weighted toward the red end of the spectrum. Scientific American does a good comparison with the various types of lighting as compared to human visibility. Here is a good chart showing the comparison:(courtesy Scientific American)
In light of this chart, it looks pretty bad according to Dr. Ramos’ research. Before jumping to conclusions, let’s put things into perspective – what is the color spectrum of sunlight? Take a look at this chart:
Notice how much sunlight is present in the 400-450nm range (where both CFLs and LEDs have emissions). Also consider that light intensity in the shade of a tree is about 20 times of that of a well illuminated office, and full sunlight is 200 times as bright. Even light from a window has twice the light of a brightly lit office, and look how much of that light is in the blue range to the left of human sensitivity. Not to mention all the light in the UV spectrum from the sun.
In light of these facts, you can see that neither CFLs nor LEDs pose any appreciable risk to the eyesight. Granted, if you look into a bright LED you will suffer damage, possibly permanent. Even more so if you look into the sun. Let’s use some common sense here, please.
Balancing the Spectrum
Now that we have established that LED lighting is in no way harmful to the eye, are there any other causes for concern in the spectra differences between different types of lighting? Yes, there are. Take a look at one more spectral graph:
As you can see both LED (and CFL) lighting has their blue emissions right in the middle of the Circadian band of sensitivity. What this means is that these types of lighting if used right up until bedtime may keep you awake at night. Does this property make these types of lighting bad? No, because sunlight will do the same thing. Natural sunlight does not keep us awake however, because the sun sets long before we go to bed. Even if we go to bed at sunset, the blue part of the sun’s spectrum is blocked by the atmosphere as the sun gets lower in the sky.
Can we just ignore this aspect of these light sources? No. As I have covered in my article Do You Have Trouble Sleeping?, you need to shut off all sources of lighting containing the color blue at least an hour before you go to bed, similar to what happens when the sun sets. That means switching your CFL and white LEDs off (or dim) and replacing with warmer lighting sources such as yellow LEDs. You should also avoid computer use late at night or install color balancing software.
You may be thinking, why don’t I just keep my incandescent light bulbs? One big problem with that is the fact they are being phased out of production and will become difficult to obtain. You will still probably be able to buy them in small wattages which will be great for late night use.
The other factor to consider is the benefits of the blue light present in LEDs. There is a benefit? Yes. Blue light is good for us. Notice that the sunlight has abundant amounts of it. We need blue lighting from when we get up until an hour before bedtime. It wakes us up and promotes a feeling of well being.
In fact, the lack of enough blue lighting in the wintertime gives rise to a malady called Seasonal affective disorder (SAD) or winter blues. The cause is insufficient blue lighting, and the cure is lots of blue light. You can even buy expensive blue lighting or also full spectrum lamps (which are also expensive). What not save yourself the trouble and expense and just use LED light instead?
Lighting and Eye Health Tips
When you buy LED lighting, be sure to get warm white LEDs. Unless you have special needs requiring the extra blue component, avoid cool white LEDs. Those are best used for special spectral needs or if you suffer from SAD. For most usage, warm white is the kind you want. These are almost perfectly matched to human eye response and have only a small blue component. They will also be less likely to keep you awake at night. Their color is also very pleasing – a nice white without a lot of yellow or blue.
Several nutrients are necessary for retina health. The lack of any of these nutrients can lead macular degeneration or other retina problems.
Vitamin A is essential to good eye health. If you have a diet rich in eggs, you probably get enough. However, if you supplement with vitamin D, it can displace vitamin A. The two should be taken together in the amounts shown. Lutein & Zeaxanthin are also essential carotenoids which are lacking in most Americans’ diets.
LED lighting is in no way harmful to your eyes. It is a wonderful full spectrum lighting, more closely resembling the natural sunlight than any other type of lighting. It is the most efficient and cost effective means of lighting available today and will be even more so tomorrow. Unlike CFLs, there is no toxic mercury. It provides instant, dimmable, directable, flicker-free and pleasant light.
Because LED lighting mimics the sun, using bright white LED lighthing sources right up until bedtime can interfere with normal sleep hormone cycles. The remedy is to shut them off an hour before bedtime and replace them with low wattage incandescent or even better – yellow LED lighting.
Don’t let the fearmongers stop this wonderful new lighting source from entering your home. The future is here, and it is LED lighting.