Gallup's annual Consumption Habits survey said this year's and 2009 smoking levels were less than half what the smoking rate was in the 1940s.
Eighty-one percent of U.S. adults said obesity was an extremely or very serious societal problem, up from 69 percent in 2005. In fact, U.S. adults are more worried about obesity than smoking.
Americans also said low-fat diets were better than low-carb: 63 percent of Americans said a diet low in fat is more beneficial to one's health, while 30 percent believe low-carb is the better option.
The annual survey also found U.S. adults spent an average $151 a week on food. This increases to $180 a week for high-income Americans and falls as low as $127 a week for low-income U.S. adults. Americans were also spending less on food now than in the past, when adjusting for inflation, Gallup said.
The Gallup poll was based on telephone interviews of 1,014 U.S. adults conducted July 9-12. It has a margin of error of 4 percentage points.