what is blue light
The blue light is pretty much everywhere. By far, the largest source of blue light is the Sun from where we're getting a whole bunch of that blue light exposure. We also get blue light from man-made light sources such as led lightbulbs, fluorescent bulbs, flat-screen TVs, tablets, cell phones, etc. All the digital devices that you have in your hands and keep in your house emit blue light.
wavelength of blue light
Blue light, in the high-energy region of the visible light, is generally defined as light ranging from 380 to 500 nanometers. To put it into context, all visible light spectrum goes from 380 to 700 nanometers, so blue light represents about one-third of all visible light. That is a pretty big chunk of all the light that we could see.
What harm can blue light do to me?
Generally speaking, if you are outside and if you're not wearing any sunglasses on a bright sunny day, and you're not wearing a hat, or nothing else to protect your eyes from not just blue light, but the ultraviolet light as well, then you could be bringing on things such as cataracts, age-related macular degeneration, and retina damage. Those are just some of the things that could happen as a result of too much exposure to, not just blue light, but ultraviolet light. In general, you always want to take care of your eyes when you're outside.
blue light eye damage
Explicitly speaking, however, if we're talking about the blue light exposure from digital devices (like a tablet, cell phone, a computer monitor, laptop screen, or your TV) there isn't any data yet that says these digital devices are pushing out enough light to hurt your eyes in the same way that the Sun would. There just isn't enough data to back up that claim. There's no proof saying that it is enough to cause cataracts, age-related macular degeneration, or retinal damage.
Of course, it all depends. This is not to say that you should forget about protecting your eyes from the blue light that is emitted from these devices. There are a few measures one can take to ease the effects, like wearing a pair of blue light filtering glasses or computer glasses. However, there is no proof that there is enough blue light coming out of these devices to harm your eyes, and that is okay from a health perspective, that is, the health of your eyes!
blue light and sleep
Blue light has gotten a bit of a bad reputation recently. There's a whole lot of things are being said of the adverse effects of it, but the truth is blue light is necessary because it helps us to maintain our circadian rhythm. The circadian rhythm is like a natural clock that we have inside of us which is triggered by sunlight in the morning. While we receive that light through our eyes, it triggers something in our brains to say it's time to get up, it is time to be active. Then, when that sunlight goes away, it's another cue telling our bodies it's time to start calming down, time to start relaxing.
Different parts of our brain are going to function differently if there is less light than more light. The baseline is that the circadian rhythm is triggered in many ways and maintained by the amount of blue light that we receive. Thus, blue light has considerable influence in the circadian rhythm.
blue light circadian rhythm
Blue light as a whole is not bad. We don't want to eliminate it all, but just don't think that the blue light that is emitted from digital devices is all good. As a matter of fact, there is plenty of evidence that the blue light emitted from these digital devices is enough to influence and throw off our circadian rhythm. Whenever there is a disruption to our body's natural rhythm, that is when a lot of health issues start to arise. A lot of scientific data links a disruption to our body's natural rhythm to health conditions such as obesity, diabetes, insomnia, depression, dementia, and a few other things.
So, it's not as simple as saying that blue lights really cause our eyes any harm. You may not see it in the health of your eyes, but you're going to see the effects of overexposure to blue light in other areas of your life, in other areas of your body's well-being.
The way to understand this and pieced it all together is as less light enters our eyes, it serves as a cue. So, our circadian rhythm is being sustained because less light is coming through. That internal clock within us is saying it is time to start winding down. We're going to be resting soon. It also serves as a cue for our brain to release a hormone called melatonin.
blue light and melatonin
Melatonin is a hormone which influences a lot of different systems within our body, and a certain amount of it is released primarily at night when there's less light. Once again, because there has been a signal sent to our brain, it's time to send out that hormone to start calming down our bodies, cooling our system down, and different things are going to start working.
There is a study that shows that just one hour of exposure to the blue light on a digital device reduced the release of melatonin to your body by 23% (in only one hour!!!). That is something that naturally decreases as we age, therefore not everybody is going to have the same amount of melatonin throughout the entire life being released at the exact same time. It's something that goes down as we age. That's why elderly people will have less melatonin in their system. As less melatonin is released, the more significant health problems we may have because of melatonin influences a lot of the other systems in our body.
blue light exposure: what is the truth?
There is indirect health damage being caused by the blue light exposure. Thus, you need to be protected. You need to know why blue light must get filtered out at certain times of the day in certain ways and of a certain amount. You don't want to eliminate all blue light from your life, and it's absurd to think that something as simple as a smartphone could throw you off and cause health-related issues like obesity, diabetes, dementia, insomnia, and a whole plethora of other things that could happen, but it's true.
We need to do a better job of educating ourselves on the real side effects and the chain reaction that occurs with blue light exposure. The more information we have, the better. We need to protect our eyes from blue light, especially during certain hours of the day when those cues are necessary for our brain to release the essential hormones that our body depends on to maintain that internal clock.
Anybody that owns a digital device, cell phone, tablet, computer screen, laptop, whatever it may be, are susceptible to those side effects triggering a chain reaction that happens when you expose yourself to that blue light during late evening hours. You want to make sure that you cut down on the amount of time that you're spending on those digital devices late at night. You want to allow your mind to have those cues, and that is where you might want to consider getting something to filter out blue light.
There's an ideal time to wear a set of glasses that are going to be filtering out blue light, or put in another way, trying to reduce the amount of blue light that you're getting exposed.
how to block blue light
One option you have is to purchase a set of glasses that filter out blue light. All these different computer glasses can help. But that's not the only option. There are lots of free options especially when the best time to filter out blue light is going to be in the late evening hours. For instance, switch your phone or tablet into night mode. There's a popular free software that you can download called flux. It's a free program that it is synced to your time zone, so when the Sun is out and bright, your screen matches that. As the Sun starts to set, so does your screen. It's not that it's going to turn off completely, but it will begin to shift in color and start to reduce the amount of blue light that's getting emitted from your laptop.
blue light glasses benefits
If you are not a fan of the sepia tone that comes out you shift into night mode, and the way that the colors look on your screen might be something that you care about, a set of computer glasses will do the job. You do not have to buy a $100 set of blue light filtering glasses because there are plenty of options out that are $12- $40. But some choices are over $100. It really depends on what you want to do and how much you want to spend. So, the options are on the table.