Most of us use backlit devices for the vast majority of our day. Think about it. We check our phones in the morning, use our computers at work during the day, and watch Netflix in the evening at home. That’s a lot of exposure to something that our ancestors spent thousands of years without. So what kind of effect is it having on our health?
Blue light plays an important role in our circadian rhythms. Early morning light (natural blue light) is actually beneficial, helping us become more alert and signalling to the body that it’s time to be awake, thus resetting the natural body clock.
There are claims of increased cancer risk and a host of other illnesses from high levels of exposure to blue light. But there’s little evidence for this and it’s not worth stressing over at this point. This is all new science and we need more tests to prove the long-term negative effects but many studies show that light from screens and other blue light-emitting devices can be harmful. A 2018 study in the International Journal of Ophthalmology found that “screen reading can lead to the occurrence and development of poor eyesight in schoolchildren, and the higher incidence of nearsightedness correlates with the increase in the length of the screen reading time”. The study also found that “blue light is associated with the formation of dry eye” and that “blue light can indirectly cause inflammatory reactions and photoreceptor cell damage after the destruction of the blood retinal barrier”.
The study recommended that “when we use blue light rich product at night, approved anti-blue light glasses or screen cover may be a good choice to avoid blue light-induced injury”.
What we know about the negative effects of Blue Light
There’s lots of speculation and emerging science on the effects of blue light on humans. But what we know so far is:
- Suppresses melatonin production
- Reduces our ability to fall into deep sleep.
- Reduces overall sleep time
A part of the eye developed to detect light, not for visual purposes, but for regulating circadian rhythms.
One of the major problems today is what we call light pollution. The streets of Tokyo are a prime example, but even in more subtly lit cities and towns of New Zealand, light pollution is a major problem. But it’s not just the light from digital billboards, shop strobe lights, building floodlights, and car headlights that cause problems. We also have screens in our cars. We watch screens on public transport and many of us spend our evenings on our phones or using laptops. Modern TVs emit
How To Block Blue Light
First of all, let’s be clear. This doesn’t have to be complicated. Dimming the lights in your home may help. Reducing screen time, especially at night, will definitely help.
To show the extremes that some people go to in order to reduce the effects of blue light, take the example of bio-hacker and founder of the Bulletproof Coffee brand, Dave Asprey. Asprey is a big fan of using red lights and red-tinted glasses in his family home. Living in a house with lighting that appears to be from a nightclub might sound like the worst thing ever. But for Asprey and his family, it’s worth it. Reducing blue light at night has improved the quality of sleep, the moods, and the energy levels of the entire family.
Other use carotenoid supplements to improve eye health. Again, there’s little evidence proving Carotenoid’s effectiveness. But what is known is that this antioxidant can be converted in the body into vitamin A, an essential vitamin for eye health.
But you don’t need to kit your house out like a photo developer’s studio or consume expensive supplements. Blocking harmful light doesn’t have to be difficult. Of course, there more blue light you block at the right times, the better. And in this way, Asprey’s red-lit house works. But for the average person, looking to sleep better and prevent eye strain, blue light blockers are the easiest, most economical, and safest way to make a massive difference.
What about software that blocks harmful light?
As you probably know, Apple release their Night Shift feature on iOS, and Google’s Android has a night time function too. At specific times set by you, your phone screen can reduce the blue tones and increase red tones on the screen. That sounds great. But it doesn’t really work. At least in the case of Apple (and most likely other phones and devices), Night Shift mod does not reduce melatonin suppression. At least not enough to make a difference. Use these device modes in conjunction with blue light blocking glasses, but not as a standalone “solution” to insomnia.
How to have healthier eyes, sleep better, and have more energy
- Avoid screens late at night
- Get out for a walk in the sunshine early in the day or on your lunch break
- Avoid staring at your computer monitor for long periods
- Look into the distance and then back at an object close by. Repeat a few times to strengthen the eye muscles
- Sleep according to your natural circadian rhythms.
- Wear blue light blocking glasses in the evenings.