Why Do Screens Destroy Our Sleep?
& one quick, permanent fix you can implement literally right now
Let’s start with the obvious. What are you reading this article on, right now?
I would bet, a screen. (-2000 odds)
If you’re one of those lucky ones that got faxed this article, you can Venmo request my bookie.
But the rest of us are looking at them all day, and are well aware of it.
This is not another generic article denouncing toxic social media, fake news or technology—it’s about understanding reality and doing something about it.
Enter blue light. Laptops, phones and tablets all emit it, and they emit a lot of it. Blue light is not a fancy term for something else — it just refers to light that is blue.
More technically, it originates from rays of light with a wavelength between ~450 and ~495 nanometers, as shown in the diagram below:

So what, you might say. Well, it so happens that our eyes are not very good at blocking blue light, and this is arguably by design.
During the day, exposure to these blue wavelengths is “beneficial… because they boost attention, reaction times, and mood.” In short, blue light actually makes you more awake.
It’s no coincidence that blue light particles also just so happen to be the perfect size to bounce off the molecules in our atmosphere, which gives the sky its blue color.
My naïve guess is that this is the reason why our eyes and brains evolved to become particularly sensitive to blue light, which is really just an arbitrary color.
In any case, it should now be clear that if blue light makes us awake like a caffeine jolt, we probably don’t want to be taking espresso shots before bed.

The research shows that looking at screens that display blue light, even 2–3 hours before bedtime, can suppress melatonin, thus disrupting your circadian rhythm and likely reducing the amount you spend in REM.
Basically, TikTok before bed literally kills your sleep.
And we all know that poor sleep can lead to heart disease, high blood pressure, and other bad things, thus killing you eventually.
So try to put aside your phone and laptop before bed, and instead read, stretch or meditate… just kidding.
That’s not how real life works out — I am currently sitting in front of my laptop at 1AM.
So here’s the real fix: install fl.ux on your computer, which automatically makes your screen warmer as the sun sets (it automatically syncs with your time zone) and enable the night shift option on your iPhone, which does the same thing.

And that’s it.
This is both better on your brain and easier on the eyes, and it’s one of those things that you can just set up and forget about.
If you want to go really extreme, change your phone to black and white.
There is also the 20–20–20 rule, which involves taking a 20 second break from your screen, every 20 minutes, and looking at an object at least 20 feet away, in order to ease eye strain.
I am not particularly fond of it as I find it disrupts deep work sessions, but I am sure it helps.
There are also blue-light filtering (BLF) glasses, which you can get through Felix Gray, or as an add-on option to your Warby Parkers. Research is still pretty inconclusive on this one, but hey, they do have some cool glasses…
Action items:
- Install fl.ux on your computer
- Turn on night shift on your iPhone