Screen light too bright, can’t get to sleep at night (now, eyes won’t focus right).

I don’t normally go to Business Insider for science news, but they’ve actually got a pretty good rundown of recent research into the problems with taking smart phones to bed with you:

Blue light is part of the full light spectrum, which means we’re exposed to it by the sun every day. However, nighttime exposure to that light, which is emitted at high levels by smartphones, tablets, laptops, and other LED screens, may be damaging your vision. It also suppresses production of the hormone melatonin, which throws off your body’s natural sleep cues.

1. The damage that this habit does to our eyes alone is both significant and surprising. Direct exposure to blue light can cause damage to the retina. The American Macular Degeneration Foundation warns that retinal damage caused by blue light may lead to macular degeneration, which causes the loss of central vision — the ability to see what’s in front of you.

3. Exposure to blue light at night can ruin sleep. Bright blue light disrupts the brain’s production of melatonin, a hormone that helps regulate the sleep cycle. That’s fine in the morning, but our brains are supposed to start producing melatonin when we are ready for sleep, and blue light interferes with that process.

4. Sleep disturbance and “light at night” have been linked to higher cancer risk, particularly for breast and prostate cancers. In addition to helping us sleep, melatonin also functions as an antioxidant. And while more research is needed, researchers have pointed to “uninterrupted darkness” as potentially protective against cancer.

More stuff at the link.