Just in time for stop-smoking season, a string of studies during the past six weeks shows that half-steps such as cutting back or exercising are no substitute for the real thing: quitting.
First, new research shows that cutting a pack-a-day cigarette habit in half - a common step by people who can't go all the way - does not reduce the risk of dying prematurely, likely because smokers puff more deeply to compensate.
"It doesn't work? That's a disappointment," said Janet Lopez, 20, a smoker in Florida who cut back recently. "I was trying to help myself."
Second, a new study shows that smokers who exercise lower their risk of dying from lung cancer, but not by much. That's sobering news for those who hoped that working out would help keep their lungs healthy.
Dispelling such myths about these psychological crutches may discourage smokers from trying to cut back or live more healthily, but it may also force them to confront the issue more directly and quit, said Cindy Vallo, program director and a quit-smoking counselor in Florida for the American Lung Association.
"Smokers come up with these things that make them feel better about their habit. In their mind, it's not as bad if they do this or that," Vallo said.
The new findings come from several new studies, including one in Norway, where researchers analyzed 51,000 people tracked over two decades with questionnaires and checkups.
The study found that among smokers who cut back from 20 cigarettes a day to about 10, 29 percent died of smoking-related causes such as lung cancer and heart disease. That's the same rate as for pack-a-day smokers.
Those who quit smoking during the study were only 47 percent as likely to die as continuing smokers. People who never smoked or who quit before the study started were only about 35 percent as likely to die from such causes, said the study, published in November in the journal Tobacco Control.
The authors said cutting back may not help because of "compensatory smoking," in which smokers take more puffs from each cigarette and inhale more deeply in an attempt to get more nicotine, a highly addictive compound in smoke.
Another study last month in the journal Cancer Epidemiology, Biomarkers & Prevention came to the same conclusion. Heavy smokers who cut consumption at least in half tested with 2.4 times more of a marker for tobacco poisons than did longtime light smokers consuming the same number of cigarettes, because of compensatory smoking.
The research contradicts the common belief that smoking less translates to a lower risk of dying, said Dr. Raja Mudad, director of thoracic oncology at Memorial Regional Hospital in Florida.
The body's processes that repair damage from smoking do not work well if cells are regularly exposed to smoke, even a relatively small amount, Mudad said.
Bob Lamendola writes for the South Florida Sun-Sentinel.