Parents have plenty of reasons to worry about screen time, from cyber-bullies to Instagram-induced low self-esteem. Should you also be worrying about blue light and HEV rays?
Digital eyestrain
Different light sources have different wavelengths and levels of energy. Blue light, which is the most common kind coming from computer, smartphone, and tablet screens, has high energy and a relatively short wavelength. Blue light or HEV light is right next to ultraviolet light on the spectrum; ultraviolet light is the source of sunburning UV rays.
Blue light is known to increase energy and focus, but it is also associated with faster aging of the eyes, difficulty sleeping, and digital eyestrain, according to the National Center to Prevent Blindness.
The American Optometric Association reports that digital eyestrain can lead to dry eyes, headaches, and blurred vision. Children may be more vulnerable to this kind of damage than adults.
What’s the solution? Limit screen time, especially before bed. The American Optometric Association points out that blue light blocking glasses or filters have not yet proven that they prevent problems caused by too much blue light. A no-screens-after-dinner rule may be more effective.
HEV skin damage
UV rays damage skin, and we all know to slather our kids with sunscreen. But HEV rays may also damage skin. There’s currently no evidence that HEV light increases the risk of skin cancer, but dermatologists think it may penetrate more deeply into skin, causing wrinkles and other signs of aging.
Studies on the subject so far have been small, narrowly focused, and sometimes sponsored by cosmetics companies rushing to jump on the blue-light screening bandwagon. Sunlight continues to be a major source of blue light, and there is insufficient evidence to confirm worries about skin damage from computers.
Other possible health effects
Harvard Medical School points to evidence that blue light from electronic devices could be implicated in diabetes, obesity, and heart disease.
Research into this issue shows a connection between circadian rhythms — natural activity patterns — and blue light. The blue light in sunlight breaks up and scatters, making the sky look blue. This light settles our natural patterns of waking and sleeping, which are called circadian rhythms. There is some evidence that blue light from electronic sources can influence our circadian rhythms. There is also evidence that disruption of these rhythms may be connected with diabetes, obesity, and heart disease.
Once again, experts recommend limiting screen time, especially before bed. Avoiding electronic light two to three hours before bedtime can help reduce blue light exposure.
Easier said than done
Screen time is hard for kids to avoid. The average American child spends three hours a day watching TV, and up to seven hours total staring at a screen.
Teens recently told Wall Street Journal reporters that they watch YouTube videos every chance they get. Researchers confirm that the average American teen is watching about an hour of YouTube videos a day. Add video games, TV, phone time with friends, schoolwork, and tablet media consumption and you can rack up a lot of HEV rays.
A Nielsen study found that 70% of tablet-owning parents of kids under 12 let their children play with the tablets. Tablets, the study found, were used to distract kids and keep them quiet. They’re also perceived as educational. Common Sense Media found that 30% of toddlers have a TV or tablet in their bedrooms. Kids under one year of age spend twice as much time with electronic devices as they do with books.
The upshot is that it’s hard to cut back on screen time, even at night. To avoid too much blue light, however, kids should not interact with screens between dinner and bedtime. That might be a good family habit to work on this year.
Think of all the alternatives!
- Have a family dance party.
- Play with the family pet.
- Enjoy board games.
- Sing or play music together.
- Read aloud together.
- Work on a jigsaw puzzle or craft project.
Reducing screen time is a good idea for most kids, even if more research on the health risks of blue light is needed. Maybe this is the year to remove TV from the center of your family time.