Blue light filters and LCD screens – the truth behind the hype.

There’s a lot of media attention and advertising time being devoted to the possible harmful effects of blue light, specifically the blue light emitted from LCD screens such as phones, tablets and computers.  The dangers suggested range from eyestrain to eye health damage such as cataracts and macular degeneration.  So how much of a risk is there?

The short answer is:  none.  That’s right, no risk of eye damage from your phone, etc.  Blue light is not inherently harmful to  our eyes; if it was, we’d all be blind just from exposure to the sky!  Also, the intensity of the light from a screen is miniscule, compared to the everyday brightness of just being outdoors.

This all started with a study ( published in 2018 by a cellular biochemist doing research at the University of Toledo.  Essentially, they bought commercially-available human cells (cervical cancer cells, actually), and then genetically engineered these cells so they produced a light -sensitive molecule that is normally only found in the eye’s light receptor cells. They shone blue light on this concoction in a glass dish to activate the light-sensitive molecule, and watched what happened.  They found that the activated molecule interfered with other molecules in the cell, and eventually the cells died.  Interesting, but nothing like what actually happens inside the light receptor cells in your eye.  Not even close.  A newspaper at the U of Toledo published a story on this research, a story which was full of erroneous leaps of “reasoning”; the paper USA Today picked up on the UT article, and BOOM – a health “crisis” was born.  Clever marketing types at eyeglass lens companies picked up on this, and quickly developed products to protect the public from this new health threat.

It’s all marketing hype, and it’s making some people richer while providing nothing of value to you, the patient.  I will admit that some patients feel that these special lenses help with their strain and fatigue, and I accept that, because hey, we don’t know everything.  But don’t buy into the scare factor that says if you don’t use our blue light filters, you could lose your vision!

So no, blue light from your cellphone is NOT going to make you blind.

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