FastCoDesign:

When I was 14, I saved up money from my first web design job to trick out a really nice gaming PC. I outfitted my computer with tons of blue LED fans, and I kept it on at night, right next to my bed. Shortly after, I realized my sleep patterns were changing. While I wasn’t staying awake any later, it now took me longer to get to sleep. Was I eating differently? Was it just a part of being a teenager? Was it the light in my room? But the orange light from my ’80s era alarm clock wasn’t keeping me up. I finally determined that it must be the particular shade of blue light from my new computer. It took me some research to realize all this, but once I did, I started turning my computer off at night. Problem solved. And when I bought my next computer, I ordered fans with orange lights.

I think it’s intuitive that lights would interfere with your sleep pattern, but turns out that blue light “inhibits the production of melatonin, the hormone that regulates our sleep cycles.”