Staring at a computer all day

According to the American Optometric Association, the average American worker spends seven hours staring at a computer screen, which can result in computer vision syndrome. “Staring at a computer screen for extended periods of time can result in visual issues, including eye strain and even retinal damage,” Dr. Ansari says. Research from the National Eye Institute showed that nearsightedness among Americans ages 12 to 54 has leapt from 25 percent to 42 percent since 1971, likely due to more time indoors staring at screens. Dr. Ansari suggests following the 20-20-20 rule: Every 20 minutes take a 20-second break to stare at something 20 feet away. “This reduces the strain on your eyes and also increases blinking, which can soothe dry and irritated eyes,” he says. Plus, staring at bright screens (including phones and tablets) decrease quality of sleep, he says, so put the phone down before bed. Here are some more habits you didn’t realize were actually bad for you—and the best ways to stop them.