They have perfectly straight, pearly white teeth.
Americans take their dental health seriously and tend to showcase a mouthful of perfectly straight, unnaturally white teeth you don’t find in many other places. In the United States, getting braces is a common occurrence in one’s early teenage years while the process of teeth-whitening can, and does, take place at any age.
Teeth whitening in America comes in many forms—from simple whitening toothpastes that include hydrogen peroxide as an active ingredient, to at-home bleaching kits, and all the way up to expensive procedures involving dental professionals and their lasers.
A mouth that seems normal to an American often seems fake to a foreigner, and for good reason—it is.