Forty years ago, the US Surgeon General sent shockwaves through the nation when he released a report linking smoking to lung cancer and other serious diseases.

In an era when about half of American adults smoked, the findings were so stunning that they were kept a closely guarded secret until their official release on the morning of Jan. 11, 1964. The day, a Saturday, had been carefully chosen to avoid causing a negative reaction on Wall Street.

GRAPHICS: Clean Indoor Air Ordinances US Adult Smoking Prevalence

Reporters were locked into a State Department auditorium with no access to telephones and given 90 minutes to read the 387-page document. Then-Surgeon General Luther Terry, MD, and the advisory committee members who had prepared the report were on hand to answer questions. Only after the conference were journalists allowed to leave the room to file their reports on a story that ranked as one of the top news events of 1964.

That first Surgeon General's Report on Smoking and Health was the first widely publicized, official recognition of the dangers posed by smoking. Its findings were based on more than 7,000 medical articles, including two major American Cancer Society studies that had shown a link between cigarette smoking and higher death rates from lung cancer and heart disease in men.

The report stated that "cigarette smoking is a health hazard of sufficient importance in the United States to warrant appropriate remedial action." The subsequent decades have seen an explosion in anti-tobacco efforts on the national, state, and local levels.

Health warning labels are required on cigarette packs, young people are restricted from buying tobacco, advertising of tobacco products has been curtailed, and many areas have clean-air requirements. In addition, many states have raised taxes on tobacco products and funded comprehensive programs to help current smokers quit and keep non-smokers from starting. Several recent studies have shown that these programs, when adequately funded, have a significant impact on smoking rates.

"In the last 40 years we have seen tremendous advances in changing people's beliefs, perceptions, and attitudes toward smoking," said Ralph B. Vance, MD, FACP, national volunteer president of the American Cancer Society. "We have come a long way from the days of smoke-filled conference rooms, airplanes, and even schools."

Nowadays, about 23% of American adults smoke cigarettes – a substantial decline from the 1960s. Smoking is also dropping among young people; about 23% of high school students and 10% of middle school students smoke cigarettes. Lung cancer cases and deaths have decreased among American men, and rates have stabilized among women.

"As a result of tobacco control, 44 million adults in the United States are former smokers," said John R. Seffrin, PhD, chief executive officer of ACS. "But we must continue our efforts, because smoking still causes too many unnecessary premature deaths each year."

Smoking kills about 440,000 Americans each year and is responsible for 30% of all cancer deaths. Some 8.6 million Americans are living with serious, debilitating diseases caused by smoking, including cancer, emphysema, bronchitis, and heart disease.

And while anti-tobacco programs clearly have made a dent in the problem, many public health advocates warn this progress is in jeopardy.

A newly released American Lung Association report found that most states fall short in tobacco control. The report analyzed state cigarette taxes, laws on smoking in the workplace, youth access to tobacco, and funding of smoking prevention programs. In a report released late last year, the Campaign for Tobacco-Free Kids found that only a handful of states fund tobacco-prevention programs at the levels recommended by the Centers for Disease Control and Prevention.

"We have the data to prove that funding comprehensive prevention programs, raising cigarette taxes, providing smoke-free air, and preventing the sale of cigarettes to children can dramatically reduce tobacco use and disease," said American Lung Association CEO and President John Kirkwood, upon announcing his group's findings. "State legislators and governors must act quickly to prevent the 1,200 deaths now occurring each day from tobacco-related illnesses."