Here’s how your smartphone is hurting your health

When you hear terms like “smartphone addiction” or “digital dependency,” you probably conjure up a mental picture of teenagers with their heads bent over their devices. But it’s a stereotype that’s not entirely accurate. True, teens are using smartphones more than ever, but adults are too—even more than teenagers.

According to a 2018 Nielsen Report, adults ages 35 to 49 spend more hours on phones and computers than younger people. In fact, the report found that adults spend more time on average checking email than their children check social media, even while on vacation. Not surprisingly, this amount of usage takes its toll.

Here are just a few of the smartphone-related problems that your adult and teenage patients (not to mention you) could be suffering from.

Texter’s thumb

You’ve heard of writer’s cramp and tennis elbow, right? Welcome to the age of texter’s thumb. More formally known as de Quervain’s disease, texter’s thumb is a painful inflammation of the tendons (abductor pollicis longus and extensor pollicis brevis) that move the thumb. It’s a repetitive stress injury due to repeated activity or grasping, resulting in swelling and pain that can run from the thumb all the way up the forearm.

“In the activity of texting, it is thought that the problem is not caused by the tip of the thumb pressing the keys on a phone, but rather the frequent traveling of the thumb over the keyboard,” wrote orthopedic hand surgeon Korsh Jafarnia, MD, Houston, TX, on his blog. “The thumb joint is not meant to move rapidly in this manner—the confined space adding insult to injury.”

Texter’s thumb may sound insignificant, but it’s no LOL-ing matter. Thumb and wrist motion may be difficult and painful, particularly when the wrist is flexed or turned, or when using the hand to pinch or grasp. Treatment involves (no surprise) giving up smartphone use for a while to rest the thumb. NSAIDs to treat inflammation and a splint for the thumb may also help.

“When pain persists despite rest and refrain from the activity causing the condition, a steroid injection may be recommended,” Dr. Jafarnia wrote. Chronic or severe cases may require surgery, followed by rehabilitation therapy. “If untreated, the synovial sheaths will continue to thicken and degenerate. This can result in permanent damage and loss of grip strength and chronic pain,” he warned.

Digital visual dysfunction

Smartphones are making us blind—both temporarily and in the long run.

Transient smartphone blindness occurs when a person is lying down (typically in bed) with one eye on their smartphone and the other eye closed and/or buried in a pillow. The open eye becomes adapted to light while the closed eye adapts to dark. In time, the bright smartphone screen “bleaches” the photoreceptors in the open eye. When the person switches to using both eyes, temporary blindness (up to 15 or 20 minutes) occurs in the exposed eye due to the reduced retinal sensitivity. While this may seem like an inconsequential problem, ophthalmologists have documented a few cases in which patients with smartphone blindness were wrongly diagnosed with stroke or multiple sclerosis.

More worrisome is the effect of blue light in causing or accelerating macular degeneration in smartphone users. Blue light is part of the visible spectrum (with high energy wavelengths of about 400 nm to 480 nm), so we see it all the time—too much of the time perhaps. It comes not only from the sun, but also from fluorescent and LED lightbulbs and digital screens. So, the more you stare at your smartphone, the more blue light your eyes absorb.

In a recent study, researchers described a substance in the retina, called retinal, that’s needed for vision—but when retinal is exposed to blue light, it triggers a reaction that kills the eye’s photoreceptors. And once destroyed, photoreceptors don’t regenerate—a deficiency that results in macular degeneration.

Blue light exposure at night can also trick your circadian rhythm into thinking that it’s daylight, keeping you awake and disrupting your sleep. So, if your phone has a blue-light filter or “night mode,” use it after dark.

Smartphone insomnia

Speaking of slumber, smartphones are also taking up time that we should be spending asleep. Researchers reported in Sleep Medicine that teens who spend more than 2 hours a day on their smartphones get fewer than 7 hours of sleep each night. The recommended amount of sleep for teens is 9 hours.

For this study, the researchers analyzed data from 2009 to 2015 on sleep and smartphone use in more than 360,000 teens. They found that teens’ sleep habits changed noticeably starting around 2012—about the same time that smartphones came into common use.

“Given the importance of sleep for physical and mental health, both teens and adults should consider whether their smartphone use is interfering with their sleep,” said lead author Jean M. Twenge, PhD, professor, Department of Psychology, San Diego State University, San Diego, CA. “It’s particularly important not to use screen devices right before bed, as they might interfere with falling asleep.”

Text neck

Do you find yourself craning or overextending your head when you’re using your smartphone? You may be one of the many people who find that using a smartphone is literally a pain in the neck.

Called text neck, this malady has been reported to be the most prevalent musculoskeletal disorder in smartphone users. In a recent study, researchers reported that the majority of smartphone users who had musculoskeletal disorders commonly adopted awkward ergonomic postures when using them, which can affect soft tissues (eg, strain muscles and ligaments, irritate tendons, and compress nerves).

“Smartphone users typically bend their neck slightly forward when reading and writing text messages. They also sometimes bend or twist their neck sideways and put their upper body and legs in awkward positions,” said one of the study authors, Rose Boucaut, EdD, MPH, physiotherapist, University of South Australia, Adelaide, Australia. “These postures put uneven pressure on the soft tissues around the spine, that can lead to discomfort.” 

Dr. Boucaut added: “It is also doubtful whether people experiencing back and neck pain (especially young people) are aware it could be as a result of excessive smartphone use. Health practitioners need to educate their patients about safe postures and curtailing time spent using smartphones to help prevent these issues.”