Overuse of teeth-whiteners appears to be the dental profession's the biggest concern. Excessive bleaching can dehydrate teeth temporarily, making them extra sensitive. As well, peroxide, which soaks through enamel to break up stain-forming molecules, can irritate gums if used too aggressively. People who want teeth whiter than nature intended, reaching repeatedly for the peroxide, suffer from "bleachorexia," a word coined by the American Dental Association.

"Many people now have teeth that are whiter than the normal color scale we used to use many years ago," said Dr. Kimberly Harms, a consumer adviser for the American Dental Association. "We now have many people whose teeth are whiter than the (official) tooth color scale." Calling it "bleachorexia," dentists say more and more people are coming in with unrealistic expectations for their teeth, wanting pearly whites that are several shades lighter than what's natural.

This morning we have a story that everyone has been talking about. A lot of people who we know are obsessed with whitening their teeth. I'm sure you know them, too. Yeah, nice, nice. And we're gonna tell you though, about the dangers of this. One doctor calling it "bleach-orexia."