For a restful night, make your smartphone sleep on the couch

We've all been there. You wake up in the middle of the night and grab your smartphone to check the time - it's 3 a.m. - and see an alert. Before you know it, you fall down a rabbit hole of email and Twitter. Sleep? Forget it. Well, I've found a $7 solution: an old-fashioned alarm clock. My smartphone has been banished from the bedroom. Sure, you can flip your phone to quiet mode. But the draw to roam in the early hours is powerful. Sleep researchers say this isn't good for you. You might as well get up and drink a shot of espresso. "It's a very slippery slope, once you've picked up your phone, to see what time it is, to checking your email, to lying awake with anxiety," said Dr. David M. Claman, director of the Sleep Disorders Center at the University of California San Francisco Medical Center. "If you wake up in the middle of the night and check your phone, you will inevitably get frustrated and worried by something you've seen, leading your body to tense up." Then it's game over. You're tossing and turning, thinking about an email, a text or a meeting in six hours. Claman said smartphones in the bedroom had led to a rise in sleep-related complaints from his patients. "For people I see in their 20s and 30s, the phone is becoming a more common contributing factor to insomnia," he said. Some large, long-term studies on sleep disorders in the United Kingdom and Finland have found that stress-related issues have led to a rise in insomnia during the last decade. In the U.S., according to the National Center on Sleep Disorders Research at the National Institutes of Health, as many as 40 percent of Americans suffer from insomnia in a given year. Ten to 15 percent have chronic insomnia. All these sleep interruptions lead to work problems. A 2011 study by the American Academy of Sleep Medicine found that insomnia costs $2,280 in lost productivity per U.S. worker every year. That adds up to $63 billion a year for the nation. The draw of the smartphone is understandable. The alarm clock is a free feature. It's also incredibly convenient - who doesn't like being able to speak to their phone and say, "Wake me up at 7 a.m."? Many Americans do like it, and they increasingly have brought their smartphones into their bedrooms. A 2013 Facebook-sponsored study by IDC Research found that 44 percent of the people who own a smartphone said they use it as an alarm clock. That number rose to 54 percent for people 18-24. Device-makers are helping the trend along and hoping these figures rise. Most new alarm clocks made today are designed to be married to a smartphone. This goes against years of research showing that screens, in any capacity, do everything but help us fall asleep. In 2012, the American Medical Association's Council on Science and Public Health said that "exposure to excessive light at night, including extended use of various electronic media, can disrupt sleep or exacerbate sleep disorders." Sleep researchers say that looking at a blue light, which is produced by smartphone and tablet screens, sets off brain receptors that are intended to keep us awake and interferes with circadian sleep patterns. Experimental research has found that if people use a tablet for up to two hours before bed, it takes an extra hour to fall asleep. Orfeu M. Buxton, a neuroscientist and assistant professor in the division of sleep medicine at Harvard Medical School, said the phone in the bedroom could set off what he called "threat vigilance," which is a type of anxiety that keeps you awake. "This means that you're never off, you're always watchful, which is a hallmark to insomnia," he said. Teenagers fare the worst. Some children in middle school not only bring their phone into the bedroom but also leave the ringer on. "I have found that 10 or 15 percent of teens in middle school are hardened insomniacs that not only sleep with their cellphones on but feel they have to be responsive to intrusion, in case a friend is in need," Buxton said. This I know: Little good comes from looking at your phone at 3 a.m. So for now, my bedroom rule is this: No gadgets allowed. Except my new alarm clock. It has no apps or Wi-Fi, but it wakes me up in the morning, not in the middle of the night.