The Mystery of Blue Light


If you’ve ever laid awake long into the night wondering why you’re not tired there could be an answer: blue light. We’ve all heard of the mysterious blue light that comes from screens and keeps us awake long into the night. But what is it and how do we protect ourselves from it?

Blue light is really what it sounds like - light that’s of a wavelength that emits a blueish tint.

In a Harvard Medical School study researchers found that exposure to blue light suppresses your body’s production of melatonin which is naturally produced in your brain and helps signal you it’s time for sleep. This means after a lot of exposure to blue light your body hasn’t been making its normal dose of melatonin which would normally signal your brain it’s time for bed.

Unfortunately for us just about every electronic device emits a higher wavelength of blue light than anything else. Laptops, cell phones, even your smart fridge can all be responsible for emitting high amounts of blue light which keeps you up late into the night. So if you’ve ever thought you’ll watch some Netflix to fall asleep - think again. The blue light emanated from a TV screen or a laptop could counteract your efforts to get to sleep.

Luckily, blue light filtering glasses are becoming more and more popular. These glasses do what they sound like - they filter out the blue light via a thin coating on the lens of the glasses. This filtering reduces your exposure to blue light and is most effective when worn in the hours leading up to bedtime.

As a full-time software engineer who stares at a screen for hours on end I invested in a pair of blue-light filtering glasses. I opted for ones that had no prescription and a tiny bit of magnification to make it easier to read small computer text. One of the first things I noticed is when I hold the lenses up to my computer screen I can see that through the lens my screen appeared much more yellow. It is pretty amazing to see the blue light getting filtered out!

Since blue light glasses are a special coating applied to the lens - they don’t have to be a big chunk of change and can be an option applied to regular prescription glasses. Mine aren’t noticeably blue light filtering unless you’re wearing them. Even retailers like Costco have an option to add blue light filtering to glasses.

The most important thing to note is the limitations of blue light glasses. Although I previous thought that blue light can cause eye strain - the real cause of the eye strain is staring at a computer screen for hours on end. The best cure for eye strain is remembering the 20-20-20 rule: looking at an object 20 feet away for 20 seconds every 20 minutes. Once I incorporated this into my routine paired with wearing the blue light glasses I noticed that my eye strain improved as well as my ability to fall asleep at night.

Blue light glasses won’t solve all of your problems but could make a big difference if you find yourself using the computer or watching TV in the hours before bedtime. Just don’t forget to give your eyes a rest once in a while and get outside for some natural light and a break from the screen.