Dry eye in the blink of an eye

By HSC Staff Writer • Published: March 24th, 2006
Category: Health in a Heartbeat

We all know how to keep our eyes healthy… eat carrots and wear sunglasses, right? What about not squinting at the computer?

A new study reveals squinting at a computer screen can cut in half how many times a minute we blink. When we don’t blink enough, we can get tearing and dry eye… an irritating and painful condition.

So what does squinting have to do with blinking? Blinking is Nature’s way of rewetting our eyes to keep them moist. We blink about fifteen times a minute, and we do it involuntarily, without even thinking about it.

We squint to bring something into better focus or to reduce glare… two things we do a lot when we stare at computer screens. When we squint, we may blink less often. And the less we blink, the more strain we put on our eyes.

Ohio State University researchers recently asked volunteers… who had electrodes attached to their lower eyelids… to squint while they looked at a computer screen. Participants blinked much less frequently while squinting. They also reported more burning, tearing, aching and dryness.

The researchers say we blink twenty-two times a minute when we’re relaxed and ten times a minute when we’re reading a book… but only seven times a minute when we’re reviewing text on a computer screen.

We can’t tell ourselves never to squint. But we CAN open our eyes to its hazards and think about the blink more often… then attempt to avoid conditions that make us squint.