When I turn off my bedroom light at night, the room is still lit up like the bridge of the Starship Enterprise. No, I'm not some sci-fi fanboy, just a gadget-happy materialist.
In one corner, I've got a desk with a PC on it. Six button lights on my two monitors glow orange. The PC power button blinks bright green. The speakers have a red light near the switch. My desktop microphone has a shockingly bright green light that casts a circle on the ceiling, as if I'm calling Batman. It's all plugged into a generic surge protector, which has a very bright red light on the toggle switch.
My wife usually leaves her work laptop, a MacBook Pro, and her personal laptop, a Dell Studio, charging in the bedroom. The Mac throbs with a blue-green light that gradually brightens, then dims, then brightens again like an airport beacon. Her Dell shines a small, dim light in the front. And the AC adapter has a light ring around the plug.
We also have a TV in the bedroom, and it has a cable DVR plugged into it. The DVR has a bright red light that's pointed straight at the bed. The TV and the DVR each has a smattering of other lights.
We've got two more surge protectors, each with a bright red light. Our e-books have lights that remain on when charging.
Our bedroom has a door to a bathroom, in which our electric toothbrushes flash amazingly bright green lights. Even when we close the door, you can see the seam around and under the door flash green! green! green!
Even with the room lights off, it's almost bright enough to read by the collective light produced by all of those status lights. And half of them are flashing. I'm supposed to sleep? Isn't this how they torture inmates at Guantanamo?
I wrote a column in this space four years ago about how incredibly annoying all these gadget status lights are and demanded that device makers get rid of them.
I didn't expect manufacturers to respond. And in fact, the problem is getting worse. The number of gadgets we use keeps growing, and each device seems to have more and brighter lights.
Since I wrote that column, new research has emerged that reveals how incredibly bad all of those lights can be for our health.
Lights on during sleep harms health
New science has shed light on various health effects of sleeping in a room that isn't dark.
Lights at night can make you depressed and fat. An Ohio State University experiment on mice led researchers to conclude that even dim light in a room during sleep may cause depression. In a different study, Ohio State researchers found that sleeping in a dimly lighted room increases the amount of hunger experienced during the day, which can contribute to weight gain and possibly susceptibility to diabetes.
Sleeping in a room with dim lights increases a woman's chance of getting breast cancer, according to research conducted at the National Cancer Institute and National Institute of Environmental Health Sciences. The reason is that the body produces a cancer-fighting hormone called melatonin at night during sleep. But this process is interrupted if the room isn't dark.