Yet for all the concern over smartphones and other mobile devices and their addictive potential, there may be more physical problems to consider: Staring at tiny screens, it turns out, is drying out our eyes, causing us to tense up our facial muscles, and even making some of us feel dizzy. Eye doctors say the most common problem is that people blink far less when their eyes are straining to read text on a small screen. People typically blink about 15 times a minute, but the average blink rate shrinks 50 percent or more when a person is staring into a smartphone screen. There are more than just dry eyes to consider. As people squint at their screens, their facial muscles contort in a way that can cause headaches. People also tend to stiffen their neck and shoulder muscles as they read from the small screens, which are often moving, even if only slightly, as they are held in the user’s hands. This array of symptoms has been dubbed Computer Vision Syndrome. Tips to help out include taking breaks every 20 minutes or so from staring at the screen, trying to blink more often, and increasing font size.
Heavy smartphone users should also be careful to avoid too much reading in bed at night, as the blue light emitted from mobile devices can suppress the production of melatonin, which helps regulate sleep.
The latest iPhone operating system can also affect a person’s sense of balance. Shortly after it was released, numerous users complained that the rapidly moving icons — that seem to zoom in and out with greater nimbleness than before — triggered dizzy spells.