CDC chief says U.S. smoking rate of 20% is 'a paradox'

After a 40-year decline, the U.S. smoking rate has hovered around 20% since 2005, although states with aggressive tobacco control programs have seen their rates drop as low as 13%, Thomas Frieden, director of the Centers for Disease Control and Prevention, said Tuesday.

"In some ways, this is a paradox," Frieden said at a news conference about a new CDC smoking report. "Tobacco control has strong bipartisan support. Even most smokers want to quit. In 2010, we know better than ever what works to reduce tobacco use."

Yet nearly 47 million adults smoke, he said. Smokers are more likely to be male, high school dropouts and living below the poverty level, according to the CDC.