By now, most parents have gotten the message that they've got to protect their kids from the sun.

So they drench them in sunscreen with SPF 50, haul the umbrella to the beach, look for the shadiest nook at the park and constantly nag them to wear hats.

But what about their sunglasses?

The consensus among pediatric ophthalmologists is that children need to protect their eyes the same way they need to protect their skin.

But exactly how much eye protection kids need hasn't been determined by medical research. There is, however, an established link between sun exposure and adult diseases of the eyes.

"A lot of the studies out there have been done on adult populations rather than children," explains William Potter, a pediatric ophthalmologist affiliated with Greenwich Hospital in Connecticut. "So while we can infer some things from that research, there's still some question about just how zealous we need to be with our kids." That uncertainty is complicated by many kids' resistance to wearing sunglasses, the same way they balk at wearing hats or protective layers of clothing.

"It's not a simple problem because a lot of kids don't really like wearing glasses," says Leslie Doctor, an ophthalmologist affiliated with another Connecticut medical center, Norwalk Hospital. "And telling parents their kids must have sunglasses is just another thing to add to a long list of things we already have to do to keep our kids sun-safe."

That said, she adds, "We do need to protect our eyes for the very same reason we put sunscreen on. You want to preserve and protect them for the long haul."

You can't really get a sunburn on your eyes during a typical day in the sun, at least not the way you can on exposed skin, Potter says. "It's sort of a myth," he says. "There is no such thing as an eye sunburn. At least not the way you might think of one."

Though studies have never looked at the direct impact of sun exposure on children's eyes, Potter and Doctor note that a growing body of evidence suggests a lifetime of sun exposure may play a role in problems such as cataracts and sight-stealing macular degeneration.

"They are diseases of aging," says Doctor. "But it just makes sense that we want to minimize exposure over the course of our lives." You may want to take extra care protecting your children's eyes if there is a family history of diseases such as cataracts.

"All things being equal, if you come from a family background where there have been cataracts, you probably stand a better chance of getting them than the next person," Potter said. So it stands to reason that kids in these families are "good candidates for sunglasses at an early age." If your child resists, don't sweat it.

"I don't know how much I want to fight with a kid who is really young about that," Potter said, adding that kids who don't want to wear them "are very good at losing them." He notes that "your eyes, like most evolved organisms, do a certain amount of adapting to stress."

You may have more luck if your child wears prescription glasses. Many eyewear manufacturers make protective clips that can be snapped onto prescription glasses to add sun protection. Some come in novelty styles and fun colors.

Potter recommends clip-ons because they tend to be less expensive than prescription sunglasses. But, he says, they make glasses heavier. "Kids have these cute little noses that make it hard to wear glasses in the first place because there's not that much to hold them on the face," he says. "If a clip makes them heavier, they can slip and be more uncomfortable."

When buying sunglasses for children, make sure they have a label promising they protect from 100 percent of UVA and UVB radiation. Probably the best way to ensure that sunglasses provide adequate protection is to look for a label affixed to the lenses stating they meet ANSI (American National Standards Institute) criteria, notes Potter.

"And if all else fails, try a baseball cap," says Doctor, adding that's her rule when her own kids balk at wearing sunglasses. "It's better than nothing."

Though studies have not measured the impact of sunlight on children's eyes, two Connecti- cut doctors say long-term exposure may be linked to eye ailments experienced later in life.