Daphine Josian Umutoni, 22, says the best way to re-create a cinema is watching television with lights off. 

She gets in front of the TV and watches from about 7pm to 10pm when her parents finally send her to bed, and, guess what? When she gets to her bed, she opens her laptop and immediately plays another movie, which she watches until her eyes decide to shut down by themselves. 

"Everything seems more clear with the lights out, all my focus is on the screen and I find it more convenient. When I get to bed, I resume the movie with the light off since I don’t want to disturb my elder sister with whom we share a room,” she says.

Just like Umutoni, many people find it more comfortable to enjoy home-made theatre with lights out and the same applies to people with offices at home who sit in the dark in front of a bright screen computer. 

Much as we get all this comfort with lights off and eyes on a clear screen, do we know the effect it has on ourhealth? Well, there is only one way to find out, keep reading this article. 

"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 television 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.

Scientific evidence

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.

Scientific literature has long supported the notion that reducing contrasts in perceived brightness between a visual display and its background will result in reduced visual fatigue and eyestrain.

 LRC researchers recently tested this hypothesis in the context of watching television

"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 Dr John Bullough, a 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.”

Screen scene effects

Felix Mugisha, an optician and eye health specialist in Kigali, says he gets people asking him a lot about watching TV in the dark and if it’s bad or how they can still watch TV in the dark but reduce the negative effects. 

"Watching television in the dark will definitely strain your eyes and can cause headaches, but will not necessary damage your eyesight,” Mugisha says. 

He explains a scenario of someone watching an action movie that has parts showing nightlife, explosions and then daylight with a lot of bright light. 

"When watching this movie, your eyes are forced to constantly adjust to different levels of lighting with the quick change of a bright screen and a dark one there after,” he says.

"When they go on for long, it makes the pupil dilate over and over. It isn’t necessarily an eye defect but it means your eyes are being strained during the course of the movie and that means you are more likely to fatigue the muscles involved.” 

Writing in Apartment Therapy, experts said they did find a few cases of studies though that did end up with the hypothesis that watching television or the computer monitor in the dark isn’t great for your eyes.

In a recent report, CNN said eye strain 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?