Drop in US smoking has slowed, despite public health efforts

The number of heavy smokers “fell substantially,’’ Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, said in a media briefing, while the number of light smokers - those who smoke half a pack a day or less - increased.

In 2010, an estimated 19.3 percent of Americans smoked, down from 20.9 percent in 2005. The percentage of smokers who puffed on nine or fewer cigarettes a day rose to 21.8 percent in 2010 from 16.4 percent in 2005, while the percentage of heavy smokers - 30 or more cigarettes per day - fell from 12.7 percent to 8.3 percent.

Still, health officials emphasize that light smokers also face the health hazards of heart disease, lung cancer, and strokes.

“The latest research leaves us less impressed with the health benefits that people accrue from cutting down on smoking ,’’ said Dr. Tim McAfee , director of the CDC Office on Smoking and Health. “We see much more dramatic benefits from people quitting altogether.’’

Massachusetts had a sharper drop in smoking rates - from 18.1 percent in 2005 to 14.1 percent in 2010 - as have most of the other New England states. Only 1 percent of Massachusetts residents smoked more than a pack a day last year, and the state’s overall smoking rate was the fifth-lowest in the country.

Smoke-free workplace laws enacted in Massachusetts seven years ago and a high cigarette tax, currently $2.51 per pack, may have contributed to the drop. These efforts, as well as support for those who wish to quit and education on smoking’s risks, help to drive down smoking rates, Friedan said.

“There’s a misperception that we’ve reached an irreducible minimum for smoking rates, and that’s very far from the truth,’’ he said. “We know it’s possible to drive down tobacco rates substantially more than we have already.’’

While the CDC recommends that states fund smoking cessation programs with 10 to 15 percent of the revenue generated each year from tobacco company settlement funds and cigarette taxes, only North Dakota met that recommendation. Massachusetts spent $4.5 million on programs such as antismoking advertising campaigns and toll-free quit lines in the 2011 fiscal year - barely 5 percent of the CDC’s recommended amount.

The federal government has set a goal to lower national smoking rates to 12 percent by 2020, which might be difficult, given that rates in many tobacco-growing states hover well above 20 percent. In Kentucky, nearly 25 percent of residents smoke - similar to the rate in Massachusetts in the late 1980s.

Smoking regulations in Southern states are more lax than in other parts of the country. In California - one of the first states to implement antismoking laws more than a decade ago - has one of the lowest rates in the nation: 12 percent

But laws cannot completely fix the problem.

McAfee said cigarette taxes appear to be having less of an impact than expected due to discounts implemented by the tobacco industry via cheaper prices per pack or coupons mailed directly to consumers.