SEVENTEEN-YEAR-OLD Maya* doesn't smoke because she's seen firsthand what harm a lifetime of smoking can do:

My grandma started smoking when she was 16. She's 65 now and has emphysema. Some days she can't even walk from her bedroom to the kitchen, she has such a hard time breathing. She has to use oxygen all the time, even when she sleeps. It's horrible—for her and for us. No thanks, never! 1

Those who don't use tobacco

Maya is one of the two-thirds of American teenagers who don't use tobacco, and she's proud of it. Indeed, for every teen who smokes, there are two who don't. The proportion is even higher among adults: Three out of four don't use tobacco products. Such figures clearly run counter to what some tobacco companies suggest in their ads: that most Americans do smoke.

Among the teens who smoke, three-quarters say they would like...