How Does Screen Time Affect Your Brain, Anxiety & Overall Health?

In light of the "digital revolution," we are spending more and more time looking at digital devices than ever before. We now have immediate and unlimited access to information and to one another. The American Optometric Association (AOA) reports that an average American worker spends at least seven hours a day on the computer either in the office or working from home. Other recent reports indicate that it could be as much as 11 hours each day that the average American adult spends looking at a screen of some kind—including mobile devices like phones.

At the same time, healthy young patients of mine in their 20s, 30s, and 40s are reporting chronic insomnia, brain fog, and short-term memory loss, as well as vision strain and headaches in droves.

While there isn't an abundance of research, a few studies are beginning to emerge. Here's what can happen if you stare at a screen all day.

The effects on your brain are both behavioral and structural.

First, smartphone addiction is real. A study of students in 10 countries showed the majority feel acute distress if they have to go without their phones for 24 hours. Meanwhile, most people are checking their phones at least 150 times a day and sending upward of 100-plus texts.

This problematic use of cellphones has been associated with anxiety, stress, and even depression1. These habits are causing what top neuroscientists have called "digital dementia," harming important right-brain functions including short-term memory, attention, and concentration in ways that may or may not be reversible.

On the structural side, individuals who are perceived as having an online game addiction show significant gray matter atrophy in various areas of the brain (right orbitofrontal cortex, bilateral insula, and right supplementary motor area) once examined on brain MRI studies. These affected areas where volume loss is seen are responsible for critical cognitive functions such as planning, prioritizing, organizing, impulse control, and reward pathways. These areas are also specifically involved in our development of empathy and compassion as well as translation of physical signals into emotion.

Additionally, kids are at risk, too. Findings from an ongoing NIH study on 9- and 10-year-olds show that those who use smartphones, tablets, and video games more than seven hours a day are more likely to have premature thinning of the cortex—the outermost layer of the brain where most information processing occurs. At this point, researchers aren't sure if that's a bad thing and won't know exactly what it means until they follow these children over time. However, the study also found that kids who had more than two hours of screen time per day scored lower on thinking and language tests.

The American Optometric Association defines CVS—computer vision syndrome—also known as digital eye strain, as a complex of eye and vision problems related to the activities that stress the near vision and that are experienced in relation, or during, the use of the computer, tablet, e-reader, and cellphone. These symptoms can include eye strain and ache, dryness, irritation, redness, double or blurred vision and burning, and even neck and shoulder pain.

In 2014 a Harvard Medical School group investigated the biological effects of reading an e-book on a light-emitting device with reading a printed book in the hours before bedtime. They reported that individuals who read on the e-book took longer to fall asleep, had reduced evening sleepiness, reduced melatonin secretion, later timing of their circadian clock, and reduced next-morning alertness than when reading a printed book. Much of this likely has to do with the fact that e-books and other digital screens emit blue light, which has been shown to interfere with the production of the "sleep hormone" melatonin which helps regulate other hormones as well as our circadian rhythms.

While the research to date linking mood and digital device addiction is still emerging, some recent studies2 are starting to link prolific social media use with increased risk for anxiety and depression. I've seen this first-hand, with countless numbers of my patients reporting anxiety, stress, and depression caused by spending too much time scrolling Instagram, Facebook, and Twitter feeds. Some even report that "social media detoxes," where they delete these apps from their phones for a few days or weeks, drastically improve their sense of well-being.

If you find yourself experiencing symptoms like insomnia, short-term memory loss, anxiety, worsening vision, headaches, or brain fog, see your personal doctor for an evaluation first, but then try limiting screen time to six hours per day, avoiding all screens at least one hour before bed and taking the weekends "off" from social media. If you immediately feel better, you have a clear indication of how screens are affecting you.

For kids, the American Academy of Pediatrics recommends3 avoiding digital media altogether for toddlers younger than 18-24 months (other than things like periodic video chatting with relatives), and limiting screen use for children ages 2-5 to one hour a day of high-quality programming, preferably with an adult. (Also consider trying out some of these amazing expert tips on how to raise a wild child in the age of tech.)

Some other precautions you can take: Load up on nutrients that have been shown to combat some of the symptoms of computer vision syndrome—specifically, the carotenoid antioxidants zeaxanthin4, lutein4, and astaxanthin5, found in green veggies and a variety of colorful plant foods like these. And, if you can't avoid using a computer or other digital device before bed, consider wearing a pair of blue light-blocking glasses in the evenings, which have been shown to6 help restore melatonin production.

From there, we should all be asking the bigger question, which is whether our technology serves us, or we are a servant to it, and how tech will affect our health and well-being in the future.