A search across the “all-knowing” internet reveals the majority of results come from folks like you and me posing the same question and everyone debating back and forth, with hardly any proof being offered.
“Is watching TV in the dark bad for your eyes?”
Variations on the question might include “Is using the computer in the dark bad for your eyes”, and with computer monitors and TVs almost all using the same technology, it’s really just the same question.
Those saying “yes, staring at a monitor for prolonged periods of time is bad for you,” refer to eye strain and the pupil’s constant adjustment to the changing amounts of light when watching TV or a computer monitor in the dark. The assumption being that with the lights on the ambient light is such that your eyes don’t need to adjust.
Those saying no repeatedly note that there is no scientific evidence, and while many people are constantly asking the question and many more strongly defending their position, actual proof is quite scarce.
Articles referencing scientific studies - both camps, saying yes or no to the issue - rarely provide a source, simply providing anecdotal mentions of studies saying one thing or the other.
Digging a bit deeper on information and “news” devoted to the topic of eye strain caused by computer monitors and TVs finds that many of the sources are eye care advocates championed by eye care businesses. Of course your car dealership service center is going to tell you that your car needs a tuneup. A few sites such as All About Vision insist on their altruistic intentions by stating their compliance with codes such as the Health On the Net Foundation, yet openly fly banner ads from contact lens companies and other industry sponsors.
We did find a few cases of studies though that did end up with the hypothesis that watching TV or the computer monitor in the dark isn’t great for your eyes, however many results showed modest results.
“Eyestrain can occur when the eyes are fixed on an object for a long period of time, there is poor lighting, or there is glare,” explains John Bullough, Ph.D., lighting scientist at the LRC and lead researcher on the television study. “One scenario believed to cause eyestrain is watching television in a dark room. In this case, visual discomfort is caused by the large difference in luminance between the television screen and the room’s dark background.”
CNN reports that eye strain indeed can occur from prolonged use of a computer or TV watching, but also goes on to say that the Mayo Clinic finds there are no long-term side effects or consequences.
So what’s the general consensus?
Whether simply opinion and belief, anecdotal, of questionable scientific claim or motive, or lack of large amounts of scientific backing, the results are a mixed bag. From all of our (admittedly limited) research and findings, we can agree that prolonged TV/monitor viewing can surely cause eye strain and have a negative affect on your vision, however moderation may be the key. The Mayo Clinic suggests the 20/20/20 rule where every 20 minutes you take your eyes off the screen for 20 seconds to look at something 20 feet away. They also suggest blinking often to keep your eyes moist, as well as a series of other tips.
So while watching TV or using the computer in the dark isn’t completely okay, it’s not the end of the world and the consequences are manageable. Besides, if someone told you definitively that it was bad for you, would that make you stop? Could you stop even if you wanted to - if your job required it for example? We all know cigarettes, beer, and candy (to name a few vices) are bad for us, but we do it anyway. And what's going on with this cell phone radiation thing anyway?