Who doesn’t like snuggling up in bed to watch a movie? Especially on a cold, rainy night. Do it too often, though, and your sleep could suffer. New studies show that leaving electronics on while you’re drifting off to sleep can induce our fight-or-flight response, putting our bodies in a state of stress, especially if the content is violent. This is bad because you miss out on deep sleep, which is when our bodies restore themselves. What’s more, the unnatural brightness of the screen reduces melatonin, which tells our bodies when it’s time to sleep. This disrupts the sleep/wake cycles, or circadian rhythms, which can lead to mood, concentration, and hormonal dysfunction.

And then there’s electromagnetic radiation or EMR, a by-product of anything electronic. Monitors, wireless device, and Internet use compound the level of EMR. Like bright light, EMR disrupts melatonin production.

The good news is that you can reverse the damage. Just turn off the TV and get some good shut-eye.