Vaping is the act of inhaling and exhaling vapor produced by an E-cigarette. It is thought to be far less harmful than cigarette smoking, because E-cigarettes don't require combustion and have fewer toxic chemicals than traditional cigarettes. That's the reason why many smokers turn to vaping as a safer alternative.
But the latest study suggests that vaping may lead to emphysema, the most common lung disease associated with smoking.
What is emphysema?
Emphysema is a long-term lung disease that causes shortness of breath. In people with emphysema, the air sacs in the lungs (alveoli) are damaged. Over time, the inner walls of the air sacs create larger air spaces and reduce the amount of oxygen that reaches your bloodstream.
Smokers are about six times more likely to develop emphysema than nonsmokers.
Vaping can cause emphysema like smoking
In the latest study, the researchers found that the lungs of vapers — like the lungs of smokers — had elevated levels of protease enzymes, a condition known to cause emphysema in smokers.
In smokers, the levels of protease enzymes would be higher, and these enzymes would damage the tiny sensitive air sac structures in the lungs that allow people to breathe, thus causing emphysema.
After measuring the levels of three key protease enzymes in lung fluid sampled from nonsmokers, smokers, and vapers, the researchers found that the levels of these proteases were significantly elevated in both smokers and vapers, but not in nonsmokers. This suggests vaping may promote emphysema like smoking.
Besides, when adding nicotine to immune cells cultured in the laboratory, the researchers observed that the cells overproduced the proteases. When adding higher levels of nicotine, the overproduction increased. This finding suggests that the elevated levels of protease enzymes may be caused by nicotine in vaping liquids.
"Our findings in this study indicate that vaping may not be safer than cigarette smoking," said study senior author Robert Tarran, Ph.D.
According to the U.S. Centers for Disease Control and Prevention (CDC), about 9 million adults in the US were regular vapers and close to 30 million had tried vaping at least once in 2014. But vaping on such large scale has been going on for less than a decade, so the long-term health effects of vaping are not yet well understood.