WEDNESDAY, March 14 (HealthDay News) -- Bans on smoking in public places, hikes in cigarette taxes and other efforts to get people to quit smoking prevented close to 800,000 deaths from lung cancer between 1975 and 2000 in the United States, a new study shows.

The findings, published online March 14 in the Journal of the National Cancer Institute, likely represent just the tip of the iceberg as lung cancer is only one of the diseases linked to tobacco smoke, experts say.

Researchers led by Dr. Suresh Moolgavkar, of the biostatistics and biomathematics program at the Fred Hutchinson Cancer Research Center in Seattle, developed a sophisticated model to estimate changes in U.S. smoking patterns resulting from tobacco-control efforts, and how these changes affected deaths from lung cancer between 1975 and 2000.

During that time, nearly 2.1 million lung cancer deaths occurred among men and about 1.05 million lung cancer deaths occurred among women. The researchers predicted that over 552,000 lung cancer deaths among men and 243,000 among women were averted by tobacco-control efforts.

While an impressive number, this is just one-third of the number of deaths that could have been averted had all U.S. cigarette smokers successfully quit smoking and no one else started after the watershed 1964 U.S. Surgeon General's report on the dangers of tobacco, the researchers calculated.

On the other hand, if smoking behaviors had not changed at all after the Surgeon General's report, an additional 795,000 people would have died of lung cancer.

"Quitting smoking most definitely reduces deaths from lung cancer. However, too many people continue to smoke," Moolgavkar said. "The most effective way to reduce the burden of lung cancer is to get smokers to quit and to prevent non-smokers from taking up smoking."

Another study author, Eric Feuer, chief of the Statistical Methodology and Applications Branch of the U.S. National Cancer Institute, said that Americans have come a long way, but can't afford to become complacent.

"We can't let our guard down and we really need to continue our efforts," Feuer said. Recent data from the Surgeon General's office showed that one in four U.S. high school seniors still smokes and three in four high school smokers continue to smoke as adults.

Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, said that "the new study is good news and very persuasive. It shows us very conclusively that less smoking means fewer smoking-related deaths."

And it is more than lung cancer rates that are likely decreasing, Horovitz noted. "Smoking cessation would also reduce rates of heart attack, stroke and the lung disease, chronic obstructive pulmonary disease," he said. "The list goes on and on."

In an editorial accompanying the new findings, Thomas Glynn, director of cancer science and trends and international cancer control at the American Cancer Society, wrote: "The good news is that we have become more aggressive in our tobacco control efforts."

Many of the deaths averted occurred in 2000, suggesting that the efforts are picking up steam. Glynn noted that his own father died from lung cancer after smoking for decades and never met his granddaughter.

"He was not one of the 795,000, but seeing [her] would have brought tears to his eyes, and thinking of him, and what he missed due to tobacco, brings tears to mine," Glynn wrote.

More information

Learn more about the risks of tobacco smoke at the U.S. Centers for Disease Control and Prevention.