Smartphones may be ruining our eyesight.

We spend so much time on our smartphones, many people are now suffering from something called Screen Sightedness.

Optometrist Dr. Jackson Lau,

It's looking at the screen, all the time, really up close and that can cause strain.

Nearsightedness is up 35% since 1997, right around the time cellphones became popular.  And Dr. Lau says the biggest rise is in children and young adults.

Kids are already playing things like Wii by the time they enter kindergarten, and schools are getting them into computers at an early age.

What to do?  Dr. Lau says after 20 minutes give your eyes a rest - even if you just look away for 20 seconds.