(AP) -- Wyoming tops the nation in chewing tobacco use, with nearly 1 in 6 adult men in that state using the product.
Government researchers found men use chew, snus and other smokeless products at much higher rates than women. In Wyoming and West Virginia, about 9 percent of all adults - both men and women - use smokeless tobacco.
The report by the Centers for Disease Control and Prevention is one of the government's first attempts to gather state-level statistics on smokeless tobacco. Past research suggests the national usage rate is around 2 percent.
The study is based on a telephone survey last year of more than 430,000 people in all 50 states. The survey asked people whether they smoked cigarettes and/or used smokeless tobacco.
Often people said yes to both. Many of the states with the highest smoking rates also had the highest use of smokeless tobacco products.
In Wyoming, for example, nearly 14 percent of smokers also used smokeless tobacco; among men, it was 23 percent.
Wyoming's "rodeo culture" includes a tradition of chewing tobacco, one CDC official said.
California had the least smokeless tobacco use, with only a little more than 1 percent of adults in that state reporting that habit.
Health officials worry about smokeless tobacco, which they believe may be a reason U.S. smoking rates have stopped falling.
Their reasoning: As smokers face more workplace smoking bans, many of them - instead of quitting - are turning to chewing tobacco or snus to temporarily satisfy their nicotine addiction and get them through parts of the day.
Indeed, CDC research suggests that some smokeless tobacco products were reformulated in recent years and became more addictive, said the CDC's director, Dr. Tom Frieden.
Health officials have also noted that most chewing tobacco use starts at a young age, that it often precedes smoking, and that over half of young males who use smokeless tobacco also smoke.
"The bottom line here: Smokeless tobacco makes it more likely that kids will start smoking and make it harder to quit smoking," Frieden said.
Officials also have been unhappy to see that major cigarette companies have taken over the smokeless tobacco product market in the last few years, and have started selling smokeless versions of cigarette brands like Marlboro and Camel.
And they're no fan of spitless, nicotine-containing snus - Swedish for tobacco, it rhymes with "noose." These are tiny pouches of steam-pasteurized, smokeless tobacco. Snus were developed to be more socially acceptable than the dark drool of traditional chewing tobacco.
Some health advocates note smokeless tobacco can cause oral and pancreatic cancer, and say it also increases risk of fatal heart attack and stroke.
"No tobacco product is safe to consume," said the American Heart Association's chief executive, Nancy Brown, in a prepared statement reacting to the CDC report.
Explore further: Explainer: What is nutrigenomics?
More information: The CDC report: http://www.cdc.gov/mmwr