Get off your smartphone... unless you want to go blind.
That advice might seem sensational, but we're getting closer to that reality. And it's all because of blue light.
I've warned my readers for years about the dangers of blue light. And a new study shows just how dangerous this stuff is...
The visible light spectrum consists of multiple wavelengths of energy. White light, like you see from the sun and artificial sources of light, is all the wavelengths combined.
But within the white-light spectrum sit different wavelengths that appear as colors – red wavelengths are the longest and blue-violet are the shortest. The shorter the wave, the higher the energy carried by the light. That's why blue light is troublesome. It carries more, potentially dangerous, energy.
Blue light influences our natural circadian rhythms. A few years ago, I noticed myself struggling to sleep after reading on my tablet. It turns out that cellphones, tablets, and even e-readers emit oodles of blue light.
Now we're learning how it permanently damages our eyes.
Here's the research published last month in Scientific Reports:
To break it down, our retina is a layer at the back of our eye that reacts to light. It triggers our optic nerves to signal to the brain what we're seeing.
One way the retina responds to light involves a chemical, called retinal. It's a molecule that changes shape when exposed to light.
Here's the scary part... these researchers exposed retinal within retina cells to different wavelengths. The blue light twisted the retinal so much that it couldn't change back to the untwisted form. Worse, that buildup of the twisted form damaged the membrane of the retina cell, causing the cell to die.
In other words, too much blue light actually kills the cells in human retinas. One more point the researchers tested: it's not just our eyes in jeopardy. Retinal moves through our bodies, so it can affect different cell types. The researchers tested other cell types as well, including heart cells, nerve cells, and even cancer cells. All the cell types experienced the same result – overexcited retinal killed the cells. And the destruction of these cells could lead to blindness.
The problem is that blue light is everywhere.
We're exposed to blue light through sunlight. That's part of how sunshine helps you feel more awake. But sunlight didn't elicit the same damage to the retina in the study. One theory is that our lens blocks some blue light, like the kind we'd get through sun exposure. It's increasing the blue light from artificial sources that seems to cause the trouble. That's why we see problems from devices that emit higher levels of blue light than other wavelengths.
Anything with light-emitting diodes (LED) or compact fluorescent light (CFL) bulbs emits higher blue-light levels too... including digital displays on things like alarm clocks.
But more than other lights, blue light comes through our electronics. Every time we glue our eyes to a flickering screen, we're taking in blue-light waves... televisions, computer screens, tablets, and especially cellphones.
Today, you can't go anywhere without seeing folks absorbed in their phones. How much time we spend on our phones varies by study, but experts peg it at about two to four hours a day. That's too much blue-light exposure.
Here are three easy ways to limit your exposure that I urge you to start today...
2. Do what I do, and turn off all electronics at least an hour before bed. Keeping electronics off or out of the bedroom entirely will create a sanctuary for sleep. That includes your phone – don't check it during the night or use it while trying to fall asleep.
3. Make mealtimes screen-free. We've noticed a growing number of folks eating out at restaurants while glued to their phones. Not only is it rude, but a recent study from the University of British Columbia showed that this behavior undermines our own happiness.
We've written before about the importance of social interaction as a way to stave off loneliness and dementia. But relying on the distraction of a phone at the table negates these benefits. An easy fix? Make a rule not to allow phones at the table. If necessary, have folks leave them in another room or pile them up on the restaurant table.
Practicing some common-sense tips to reduce screen time will help you sleep better, feel happier, and most important: save your eyes.
What We're Reading...
- Did you miss it? Our article on how blue light affects cortisol levels.
- Something different: Wasps get drunk and belligerent.
Here's to our health, wealth, and a great retirement, Dr. David Eifrig and the Health & Wealth Bulletin Research Team August 14, 2018