You know that feeling -- the ache behind your eyes, the heavy feeling of your eyelids, the redness and under eye circles you see looking in the mirror, and that intense sensitivity you get when you look at bright lights or step outside of your workplace and venture outdoors.  This feeling of light sensitivity and tired eyes has a name -- digital eye strain.  For 65% of Americans digital eye strain is wreaking serious havoc on work performance, and how your eyes feel when you're not logging those long hours at your computer and cell phone screen.  The average American spends nearly 6 hours a day using mobile digital devices and almost 11 hours daily when you include time on desktop computers, laptops, and watching TV!  Our eyes struggle adapting to light after logging long hours in a digital environment for two big reasons:

Have you ever noticed that when you use a computer in a dark room, a faint blue glow is emitted from the screen?  That blue glow emanates from most electronic devices:  your phone, your computer, your tablet, your TV, and any LED or fluorescent light source.  Blue light is an increasingly large part of our world, but what is it potentially doing to our bodies?

How does your body know when it is time to sleep?  The body's sleep cycle is governed by melatonin; higher levels in your body induce sleep.  Melatonin release is triggered to a large degree by light -- darkness causes an increase in melatonin, and light reduces the amount in circulation.  But different wavelengths of light seem to have different potency.  Blue light (like that emitted from electronic devices) has a more potent effect than other wavelengths, dampening the melatonin response more than longer light wavelengths like red (which you would find in firelight).

What does all this mean to you?  The longer you are exposed to light, and especially blue light levels, the less your body will signal to sleep.  Sleep is important to repair the bodies daily wear and tear, and we don't know all the benefits that really occur for brain function (so much for us to still understand).  But we all know how much a good night's sleep can mean for the next day's performance.  Reduced sleep has been linked to depression, obesity, heart disease, diabetes and even cancer!

Blue light may have an even bigger impact on eye health specifically.  Short wavelength light (like blue) has a higher impact on damage to ocular tissue like the retina and the lens.  This increases the rate of cataract formation, and is associated with higher rates of macular degeneration in studies performed with rats.   We all know the dangers of UV light, and the importance of wearing sunglasses, but are any of us thinking to wear sunglasses while on the computer for long hours?  New studies are showing us it is time to rethink our eyes' health needs and what we can do to protect the eyes from blue light damage.

So what can we do?

f.lux is a free Windows download that changes your computer monitor's color display to match the surrounding light levels of the time of day.  The premise here would be to reset your body to normal melatonin secretion timing by matching your computer to surrounding daylight.  The computer screen will be brighter in morning, and reset to low and more red wavelength light in the evening to encourage melatonin release so that you can get a great night's sleep.

To protect your eyes from potential blue light/short wavelength UV radiation effects, we need a UV protective lens.  Sunglasses are typically much too dark to wear at the computer screen, but even clear lenses can be made with a large degree of UV protection.  Materials like polycarbonate have innate UV protection (and are shatter resistant).  In addition to most quality prescription glasses being made from polycarbonate, more and more electronic devices may be making the switch.  Nokia phones already use polycarbonate screens, and the iPhone 5c is slated to do so as well.

Gunnar Lenses are marketed towards computer and video game users to increase comfort and block out that detrimental blue light!

For maximum blue light protection, yellow tinted lenses are your best choice.  Yellow filters block blue light out of the spectrum and let yellow (lower wavelength light) pass through.  If you have had cataract surgery, you may notice that the implant that they put inside the eye often has a yellow tint for this protective reason.  And yellow tinted lenses also have an added plus of increasing contrast and decreasing glare at your computer screen, making them ideal for computer use!