Dr. David Burns, the study's lead author, said the report supersedes a 1981 recommendation by the U.S. surgeon general that smokers switch to light cigarettes if they can't quit.
"That was our recommendation at that time. It turns out to have been a bad mistake," said Burns, who helped edit the surgeon general's report.
The new report says the standard machine test used by the government for decades to determine how much tar and nicotine smokers inhale is seriously flawed, reports CBS News Correspondent Sharyl Attkisson. It turns out all those "low tar" and "light" cigarettes aren't any safer for smokers than regular brands.
Dr. Burns has worked on most surgeon general's reports on smoking since 1975 and was asked if the numbers that have been advertised and put on the cigarette boxes all these years are a fraud. He said, "That's quite correct. This is the largest public health fraud in the last fifty years."
Fraud because, as a 60 Minutes II investigation revealed, the tobacco companies knew it decades ago: the test machines don't smoke the way humans do. Internal documents show big tobacco designed cigarettes that produce low-tar numbers on the machines knowing full-well that actual smokers would "compensate" and get more tar.
"They pull harder on the cigarettes, they take bigger puffs, they inhale more deeply, they smoke more cigarettes per day," explained Burns.
In addition, smokers can inadvertently cover ventilation holes in the filter designed to lower tar levels.
"When they do that, they get a full dose of tar and they don't have any risk reduction," Burns said.
Burns and his colleagues spent the past three years reviewing five decades worth of data examining low-tar cigarettes. They found that some people who switched to low-tar brands smoked more to get the same amount of addictive nicotine, since the ratio between tar and nicotine generally remains the same in all cigarettes.
Tar is a carcinogen that is produced when tobacco is burned. It helps deliver nicotine to smokers. Low-tar cigarettes are supposed to have less than 15 milligrams of tar.
The study found that people who switched to light brands typically thought they were reducing their risk of developing smoking-related disease and that tobacco companies contributed to those assumptions through advertising and marketing campaigns.
"The results of the review are clear. There is no convincing evidence the changes in cigarette design over the last 50 years have reduced the disease burden produced by cigarettes," Burns said.
Sharon Boyse, the director of research for Brown & Williamson Tobacco Corp., the nation's third-largest tobacco company, did not dispute those findings. But she said it's imporant to note that, if smokers are aware of how they smoke, light cigarettes can deliver less tar than regular ones.
The World Health Organization is sponsoring talks on an international convention meant to reduce smoking and tobacco-related disease, which kills 4 million people each year worldwide. One of the provisions is for a ban on terms such as mild and low-tar.
John Kirkwood, chief executive officer of the American Lung Association, said health groups sent letters Tuesday to members of Congress and the Bush administration calling for Food and Drug Administration regulation of tobacco. They also sent letters to tobacco companies urging them to voluntarily stop using low-tar labels on their cigarettes.
Boyse said Brown & Williamson opposes such a ban. A spokesman for Philip Morris Inc., the nation's largest tobacco company, said the company would support greater regulation of the terms "low tar" and "light."
The effort to produce and market low-tar cigarettes gained momentum in the 1960s, after public health advocates said cigarettes with less tar would produce less cancer. But studies by the American Cancer Society in the 1960s and 1980s found lung cancer death rates among male and female smokers rose even as tar levels in cigarettes dropped by 60 percent.
The NCI report says public health officials who backed the production of light cigarettes failed to take into account the highly addictive nature of nicotine and the difference in actual tar and nicotine levels taken in by people and testing machines.
Attending a news conference to announce the report were former U.S. Surgeon General C. Everett Koop and gun-control activist Sarah Brady, who is battling lung cancer. Through tears and coughs, Brady said she was among those who switched to light cigarettes thinking they would be better for her.
"Never allow yourself to get into the predicament that I'm in," said Brady, who has been unable to quit smoking. "The switch to low-tar lured me into a feeling of false security."
© MMI, CBS Worldwide Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report