It may be riskier for your lungs to smoke cigarettes today than it was a few decades ago, at least in the U.S. New research that blames changes in cigarette design for fueling a certain type of lung cancer. Up to half of the nation's lung cancer cases may be due to those changes.
Smokers once tended to get a form of lung cancer called squamous cell carcinoma, which strikes cells in larger air tubes. Then doctors noticed a jump in adenocarcinoma, which grows in small air sacs far deeper in the lung.
Initial studies blamed the introduction of filtered, lower-tar cigarettes. When smokers switched, they began inhaling more deeply to get their nicotine jolt, pushing the smoke deeper than before.
The new study found an additional wrinkle to the problem -- the increase in a kind of lung tumor called adenocarcinoma was higher in the U.S. than in Australia, even though both switched to lower-tar cigarettes around the same time. The most likely explanation is a change in the cigarette; cigarettes sold in Australia contain lower levels of nitrosamines, a known carcinogen, than those sold in the U.S.
View the full article here.