How to avoid twenty-first century health problems, from tablet neck to earbud-related hearing loss.

Getty Images There was a time, not too long ago, when a phone was just a phone, sky-high heels weren't sold in every mall, and you had to catch your favorite TV show when it actually aired. There's no going back—and who wants to?—but our contemporary world is bringing its share of health hazards that were once either rare or unheard-of. Check out where our text-happy, music-obsessed, stiletto-loving lives can lead—and what you can do to make these new risks a thing of the past.

Next Page: Tablet neck and BlackBerry thumb [ pagebreak ]


Getty Images Tablet neck and BlackBerry thumb
We've all been there: unable to stand in line at Starbucks or wait for a movie to start without checking our phone as impatiently as if we had a loved one in the ER. Click away, but know that all that hunching over and tapping on handheld devices, like tablets and smartphones, is leading to more—and younger—patients with arthritis and tendinitis in the elbows, neck and thumbs. In a study in the journal Applied Ergonomics, for instance, 84 percent of mobile-phone users reported having pain in at least one body part, most often the base of the right thumb. "Even light pressure can be magnified 5 or 10 times at the base of the thumb joint," causing strain, says Kenneth Means Jr., MD, a hand-surgery specialist at MedStar Union Memorial Hospital in Baltimore. So-called BlackBerry thumb could eventually require surgery, he warns.

That doesn't mean you have to give up Instagramming, but do take some simple precautions while you type. First, Dr. Means advises, hold up your phone to about chest-high when you're looking at the screen—another Applied Ergonomics study shows that as many as 91 percent of us may be staring down at navel level, straining the backs of our necks. If you have a tablet, use a stand instead of placing it flat on a table or holding it up; both positions can curve your shoulders painfully. Get up and stretch periodically while using phones and tablets, and try not to slam your fingers down on the screen or keyboard. Finally, consider making calls (remember those?) instead of so many texts and e-mails.

Next Page: Earbud-induced hearing loss [ pagebreak ]


Getty Images Earbud-induced hearing loss
Once limited mostly to construction workers, rock stars and the elderly, noise-related hearing loss is now a concern for regular folks of all ages. That's according to a report from the Johns Hopkins School of Public Health, which stated that the country may be facing an epidemic, partly from "the growing use of personal listening devices." Moreover, this hearing loss and related problems—like tinnitus, or buzzing and ringing in the ears—are occurring earlier, and showing up more profoundly once they set in. "I have more and more younger patients lately asking to be tested because they're worried about their hearing," says Jane Sadler, MD, a family practitioner at Baylor University Medical Center in Dallas.

No wonder: Unlike the bulky Walkman headphones of decades past, earbuds pipe high-volume, high-fidelity sound right through your eardrum, and their tiny size—not to mention the ubiquity of portable listening and viewing devices, like your Kindle Fire or iPod—makes it convenient for you to listen to tunes and watch TV shows and movies anywhere, anytime. Long or repeated exposure to sound over 85 decibels can damage your hearing; an MP3 player at full volume is around 105 decibels—louder than a power drill or a passing motorcycle.

The solution, naturally, is to turn down the volume, and limit the amount of time you have those wires sprouting from your ears. Try following the 60/60 rule: listening to music through your earbuds for no more than 60 minutes a day, using 60 percent of the maximum volume. Better yet, spring for noise-canceling or noise-isolating buds—or best of all, sport old-school headphones. They're generally safer, Dr. Sadler says—as long as you're not walking around in traffic with them on!

Next Page: Screen-related sleep disorder [ pagebreak ]


Getty Images Screen-related sleep disorder
Raise your hand if you sleep curled up with your iPhone, or stay up too late to watch your favorite television shows in real time (Mad Men, we're giving you the side-eye). Beware: More and more research suggests that blue light from a light-emitting diode (LED) screen—the type of screen on most computers, phones, TVs and other devices these days—can inhibit the production of the sleep-inducing hormone melatonin and disrupt our circadian rhythms. Researchers think this is because LED-generated blue light emits wavelengths very similar to daylight, so it can make our bodies think it's daytime, all the time.

In a 2011 study in the Journal of Applied Physiology, participants who viewed an LED screen at bedtime had melatonin levels that took longer to rise and remained lower during the night than when they looked at old-fashioned fluorescent monitors. This doesn't give fluorescent lighting a pass: Other research has found that energy-efficient fluorescent bulbs—which release blue light—suppress melatonin more than traditional incandescents (which emit a red-orange glow that's less similar to daylight) and can keep people awake longer. Studies like these prompted the American Medical Association last year to issue a report that "exposure to excessive light at night, including extended use of various electronic media, can disrupt sleep or exacerbate sleep disorders."

No, you're not going back to a dumbphone or a computer from 1993, but you can turn down your screen brightness at night, or install the f.lux app, which automatically adjusts the light your computer emits depending on the time of day and where you are. Better yet, do some reading under an incandescent light when you're winding down at night. Another solution: "I tell people to do stretching and yoga before going to bed," Dr. Sadler says, both to unplug and to relax yourself into a sleepier state.

Next Page: Stiletto strain [ pagebreak ]


Getty Images Stiletto strain
High heels have been fashionable for—what?—centuries; the stiletto debuted back in the 1950s. Then Sex and the City made Christian Louboutin and Jimmy Choo household names. Today, spike heels are more popular than ever, thanks to the proliferation of lower-priced—and, experts warn, often less-stable—models sold at chain stores for those of us who can't swing the designer version. They're even popping up at the gym, replacing sneakers in fitness classes such as the Stiletto Workout.

Podiatrists have been watching this trend with some alarm. "The higher you go, the more changes in your gait pattern and the more stress on your feet, knees and back," says Marlene Reid, DPM, of the Family Podiatry Center in Naperville, Ill. "Potential problems are going to be greater." In fact, she prefers patients to wear shoes with heels under 2.5 inches. Researchers from the University of Southern California reported last year that very high heels (we're talking over 3.5 inches here) were significantly more likely to lead to foot pain, ankle stress and an increased risk of sprain than half-inch heels. Another study found that super high stiletto heels were more likely than medium heels to cause varicose veins, which can lead to fatigue and pain. And in 2011 a study at Iowa State University found that the higher the heel, the greater the stress on the knees and the risk of osteoarthritis.

Don't kid yourself that wedges or platforms are a safer bet, Dr. Reid says. They may place your foot at a less-severe angle, but your staccato walk is still putting an unnatural burden of weight on the small, delicate bones of the feet and toes. Her advice: If you must wear towering heels, give your feet a rest and go low the next day.

Next Page: Offbeat biorhythms [ pagebreak ]


Getty Images Offbeat biorhythms
We live in a world where the gym never closes—and neither does the drive-through, for that matter. Our 24/7 lifestyle can have potential health consequences that researchers are only beginning to understand. For example, staying up late may predispose us to digest food differently, possibly contributing to obesity. In one study, mice exposed to dim light at night gained 50 percent more weight than mice kept in a natural-light-cycle environment—even though both consumed the same number of calories and had similar activity levels.

Studies also find that folks whose routines are not in sync with regular circadian rhythms—like people who work at night and sleep during the day—might be more vulnerable to heart disease, depression, diabetes and cancer. "We evolved under cycles of light and dark," says Richard Stevens, PhD, of the University of Connecticut Health Center. "Modern lighting has turned that on its head."

So if you're up late—or wake in the middle of the night—keep lights and activity as low as possible to stay in tune with your body clock, he says. And remember: "It's not a time to snack."