Cooper said recently on his syndicated talk show he spent 2 hours on a boat in Portugal without sunglasses and ended up temporarily blind for 36 hours.
"I wake up in the middle of the night and it feels like my eyes are on fire, my eyeballs, and I think, 'Oh maybe I have sand in my eyes' or something. Anyway, it turns out I have sunburned my eyeballs," he said on "Anderson Live." "I had no idea you could do this."
Exposure to sunlight, including the bright glare off water or off snow during the winter is very dangerous to the eyes, especially those of children. The American Academy of Pediatrics says children's eyes are at increased risk for permanent damage from sunlight until they are at least age 10 because their eyes are highly sensitive and still developing.
Cooper got quick medical attention and his eyes are supposed to be fine, but 90 percent of total lifetime damage from the sun's harmful rays occurs by age 18, the academy said.