Studies have shown that technology such as smart phones, computers and laptops has affected children's communication skills and personal relationships. But now there's evidence it might also be affecting their eyesight.

Hamilton-based optometrist Nicholas Despotidis, or "Dr. D" as his patients call him, is the co-author of a new book, "A Parent's Guide to Raising Children with Healthy Vision." He and another New Jersey optometrist, Dr. Noah Tannen, agree that technology is responsible for an increased incidence of myopia (nearsightedness) in children.

Myopia means more children are wearing glasses and can result in serious visual problems and blindness later in life.

Despotidis said 30 years ago, myopia was not very common but over the past few decades he's seen more and more children suffering from it. He said technology plays a key role in myopia.

"What studies have shown is that children need daylight to preserve their eyesight and children are not playing outside as much as they've done in the past," said Despotidis.

He said if a child spends at least 14 hours outdoors per week — that's two hours a day outside — there is reportedly a 2 percent reduction in the odds of developing nearsightedness.

So it turns out that electronics are keeping kids inside longer, which is contributing to them developing nearsightedness, he said.

He added that parents need to know that while they should be encouraging their children to stay inside and do their homework, they also need to encourage them to go outside. Playing outside, said Despotidis, not only preserves a child's eyesight, it also enhances social skills that they cannot get from electronics.

He suggested not having a cell phone around while doing homework. Do not have any electronic device at the dinner table or in the bedroom at night. Kids tend to look at the phone right before bedtime, which in turn can affect their sleep patterns and if it's there on the nightstand, it will be the first thing they see in the morning.

He said the younger the child develops myopia, the more rapidly their eyesight deteriorates. So besides needing glasses, children may also turn into introverts, Despotidis said. If myopia goes unchecked, it will progress as the child ages.

As the myopia increases in magnitude, he said it makes that adult now much more likely to lose their sight from a side effect of myopia like a retinal detachment or glaucoma.

He said he cannot stress enough "that just two hours a day of daylight helps possibly inoculate children from developing a very serious visual condition. So sometimes the simplest things are the hardest to implement."

Both doctors and authors pushed the American Academy of Pediatrics' recommendations that children under 18 months get zero time with a screen and that those ages 2 to 5 be limited to 30 minutes a day. They also suggested that all elementary school children avoid electronics during the school week.

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