Blue light has become a serious issue in the last decade or two. Thanks to all of the devices that are in our homes later and later into the day, people are starting to experience the harmful effects of it more and more.
Although people are beginning to learn more about how it affects them, many of you want to know how blue light can affect your child.
While the effects are very similar to what happens in adults, there are some key differences you need to be aware of in your children. Namely, how sensitive their eyes are to it, how it affects their sleep, and just how important sleep is for young children.
What is blue light?
When we talk about “blue” light, what we’re referring to is specific wavelengths of light that we can see. All visible light runs on a spectrum, and there is a segment of that spectrum that is visible to the human eye. That is what we call the “visible light spectrum.”
Another term for it is “HEV,” referring to “high-energy visible light.” We use this distinction because many wavelengths of light are actually invisible to our eyes. Across the entire spectrum, we can only see wavelengths between around 380-700 nanometers.
Each wavelength appears to be a slightly different color. Lower wavelengths are closer to blue or indigo, and the higher wavelengths start getting orange and red.
When you look out at light from the sun during the day or from anywhere else, you may or may not notice these colors, but that’s because you’re not looking at an isolated wavelength. Instead, most light is seen as a spectrum of different wavelengths/
What we refer to as “blue light” is light that is between about 380-500nm in wavelength. You’ll see plenty of this coming from the sun—in fact, it makes up about one-third of all visible light. The issue is not blue light coming from the sun, as that’s nothing new.
The reason this has become a problem is that we are now receiving lots of this harmful light at later and later hours of the day. There are a few things that blue light does that makes this a problem.
How is blue light harmful to adults?
Blue light during the day is an integral part of our daily lives. When our eyes see blue light, it prevents our brain from producing the sleeping chemical melatonin. This interrupts our circadian rhythms and can affect both the quality and amount of sleep that we get.
Research shows that using a blue-light emitting device close to bedtime can make it more difficult to fall asleep and can affect your ability to go into REM sleep. This means you’re getting much lower-quality rest, as well as getting less sleep overall.
This is the most researched issue in regards to blue light, but there are other potential issues as well. With digital devices specifically, there is a condition the American Association of Optometry calls “computer vision syndrome” or “digital eye strain.”
Over time, the extended use of digital devices can lead to eye strain, soreness, headaches, blurred vision, or a number of other symptoms. This is not solely because of blue light, but also due to the brightness of digital screens and the amount of time we spend looking at them.
On average, adults spend around 11 hours each day looking at a screen. This could be a phone, laptop, television, tablet, or another device. That’s nearly half of an entire day, including the time you’re asleep.
It is this prolonged, extended exposure to digital blue light that has created the problems. In adults, this can lead to a number of the symptoms laid out above, but many adults are able to self-regulate their screen time. And in some cases for those who work digitally, they have no choice but to spend that much time with screens.
But with children, it is a slightly different situation. They may not understand that a screen is not healthy for them, and there are other concerns with child screen time, as well.
How does blue light affect my child?
While children experience many of the same symptoms from blue light as adults, there are a few additional concerns, as well. According to the CDC, children’s screen time increases as they get older.
They found that children between 8-10 spend about 6 hours, 11-14 around 9 hours, and teenagers 15-18 closer to 7 and a half. However, at younger ages, it is even more of a concern.
The American Academy of Pediatrics recommends no more than one hour of screen time for any children aged 3-5, and none at all for children younger than this if possible.
Research is still being done, but it seems as though prolonged screen time may have an adverse effect on the brain development of young children. Screens and blue light are incredibly stimulating for children under 5, so it’s important to limit how much time they get.
However, what about older children? Today, many children are required to use screens for homework and other school activities. For them, limiting screen time is only one piece of the puzzle.
How to avoid harmful blue light
For those children who can only limit their screen time so much, there are other actions you can take to protect them from the blue light coming from their devices.
When they are using screens, it can be helpful to have some sort of blue light filtering. This can be in the form of software on many devices. For example, all Apple and Android phones feature some form of “night mode” or “blue light filter.”
When turned on, this filters out the majority of blue light coming out of the screen. This makes the screen look a little more orange, and it is incredibly helpful late in the day.
Another option is to use a form of blue light glasses. These are lenses that do this same filtering for you. If your child already wears glasses, you can usually get blue light filtering added to their lenses.
However, if they don’t already wear glasses, you can also get them blue-light filtering glasses that are made just for digital screens. At Look Optic, all of our frames are available as readers, but you can also get them with no magnification.
This is especially helpful for younger children, as they may not remember to turn on filtering software on their devices. If they are wearing blue light glasses, they’ll get an even better result than with just the software.
Below are a few of the common questions that we get regarding blue light and children. This is not an exhaustive list, but we hope you’ll find it helpful.
Is blue light more harmful to children?
This is a question that we get often, and the answer is really that it depends. In very young children, below age 5 or so, then yes. At this age, screen time and the potential damage to their eyes can be much more problematic than in adults.
However, once children reach around age 10, it becomes a slightly smaller concern. You should still seek to keep their recreational screen time to a minimum, but it is similar to what you would seek to do as an adult.
Does my child need blue light glasses?
This will depend on your specific child’s circumstances, but we would usually recommend it in the following situations:
- Your child has to use digital devices for homework and other school activities
- Your child is under the age of 10 and uses screens for any purpose
- Your child uses screens recreationally, including watching television or reading on a tablet
- Your child is experiencing any kind of headache, blurred vision, eye strain, or other symptoms associated with CVS
If your child falls into these categories, it may be helpful for them to wear lenses that help filter out harmful blue light.
Is there a time when I should take screens from my children?
Although blue light can be an issue at any time of day, it is most prevalent in children late in the evening. Whatever your child’s bedtime is, it is usually recommended to remove or limit screen time around an hour or two before that time.
If they are exposed to blue light that close to the time they try to sleep, it can hurt their ability to fall asleep and affect the quality of the sleep they get.
If they have to use screens late in the day, optometrists recommend filtering the blue light out of their screens through either software or some form of filtering lenses. However, the preferred option is to remove screens entirely at that point in the day.