Smokers who switch to a low-tar, light or mild brand of cigarette will not find it easier to quit and in fact may find it harder, researchers reported on Tuesday.

They found that smokers who traded to light cigarettes were 50 percent less likely to kick the habit.

It may be that smokers think that a lighter brand is better for their health and is therefore an acceptable alternative to giving up completely, Dr. Hilary Tindle of the University of Pittsburgh School of Medicine, who led the study, said in a statement.

Her study of 31,000 smokers found that 12,000, or 38 percent, had switched to a lighter brand.

A quarter said they switched because of flavor but nearly 20 percent said they had switched for a combination of better flavor, wanting to smoke a less harmful cigarette, and as part of an effort to give up smoking completely, Tindle's team reported in the journal Tobacco Control.

Those who switched brands were 58 percent more likely to have tried to quit smoking between 2002 and 2003 than those who stuck with their brand. But they were 60 percent less likely to actually succeed in quitting, Tindle's team found.

Forty-three percent of smokers reported a desire to quit smoking as a reason for switching to lighter cigarettes. While these individuals were the most likely to make an attempt, ironically, they were the least likely to quit smoking, Tindle said.

Other research has shown that so-called low-tar cigarettes have just as much tar, nicotine and other compounds as regular cigarettes, making their .

The U.S. Food and Drug Administration was given the power to regulate cigarettes in June and was immediately sued by companies such as Reynolds American Inc and Lorillard Inc. Altria Group Inc's Philip Morris unit, the nation's largest tobacco company, supports FDA oversight.