Kids and Blue Light (Part 1 of 4): Frequency and Duration

This is part one in a four-part series guest-written by nationally recognized blue light expert, Gary Morgan, OD.

Kids today are being introduced to digital technology earlier than ever. From speech training to potty training, many boys and girls are learning to tap and swipe before they walk and talk. But while there are obvious benefits to getting our kids ahead of the learning curve with digital technology, there’ a less beneficial result of all that screen time.  

​In this four-part series, we’re going to examine three primary reasons why kids could be at greater risk of blue light exposure than adults, and how you as an eye care provider can help.  ​

Increasing Frequency and Duration

We are in year 10 of the evolution of our visual environment. The first iPhone^® was released in 2007, and the first iPad^® in 2010.  In 2014, the final step of legislation to convert to energy-efficient light bulbs in the US was completed. These events have exposed us to more indoor blue light than at any point in human history.  And there is perhaps no group taking in more blue light than children.  

According to a recent VSP^® study, the average American child spends 50,000 hours (1/3 of their lives) on devices by the age of 17.¹ So it’s not surprising to find that 55.6% of parents say their kid(s) experience at least one common symptom of digital eye strain.

In addition to gaming and socializing, many of today’s children are turning to computers, tablets and smartphones for their daily school and homework activities. Pencils, erasers, and textbooks are rapidly being supplanted by a finger and a touchscreen.

A recent report showed that in 2014, the minutes per day spent looking at mobile devices surpassed the number of minutes spent looking at a TV screen.²

Does Frequency + Duration = Digital Eye Strain?

The number of times and the length of time that a child looks at a screen during the day affect symptoms of digital eye strain. But why?

Short-wavelength blue light is myopically defocused in the eye. Digital screens emit blue light throughout the blue light range, 400-500 nm.  While peak output of these screens is between 440-460 nm, the shortest, most myopically defocused wavelengths may be the most significant in contributing to the symptoms of digital eye strain. 

Essentially, the eye can’t physically bring these wavelengths into focus. Therefore, spending long hours reading studying, gaming, or socializing on digital screens can induce feelings of eye fatigue.

Reducing the frequency and duration of exposure doesn't seem likely anytime soon. In fact, with our ongoing shift towards a digitally dominated lifestyle, blue light exposure is likely to get worse before it gets better. Therefore, it's essential to provide patients - and parents of patients -  the optical solutions and education to help reduce the amount of blue light reaching a child's eyes. 

In part 2 of our series on kids and blue light, we’ll be discussing pupil size and why it could be a gateway for blue-light-related issues in children.

Read Part 2 of the Series

About the author: Dr. Gary Morgan has been in private practice for 25 years in Arizona, with an emphasis on the care of patients at risk of, or with AMD. An advocate for innovation, he serves in a technical advisory capacity to ophthalmic industry enterprises focusing on spectacle lenses, nutraceuticals, and telemedicine that are intent on lessening the effects of AMD and blue light.

1. VSP, “Should You Be Concerned About Blue Light Exposure? (Infographic), 2015
2. Ide T, Toda I, Miki E, Tsubota K. Effect of Blue Light-Reducing Eye Glasses on Critical Flicker Frequency.  Asia-Pacific Journal of Ophthalmol, Volume 4, Number 2, March/April 2015