Let’s face it—debates over e-cigarettes won’t be over anytime soon. Users (and, of course, manufacturers) say that they are safer than “real” cigarettes and they help people quit smoking. And unlike the treasure trove of damning health evidence about “real” cigarettes—the latest even adds schizophrenia to the list—research about the health effects of electronic cigarettes is truly in its infancy.

But don’t let that fool you, because one thing is becoming clear—inhaling nicotine…along with the other compounds in e-cigarettes such as formaldehyde…is far from harmless for your lungs. We’ve already told you that vaping (inhaling the vapor) causes temporary constriction in the lungs and that the vapor contains carcinogenic nitrosamines, which newer research has confirmed.

The latest news: Researchers have shown that vaping may damage the cell barrier that protects the lining of the lungs, called the endothelium. In the study, the researchers exposed human and mouse cells and live mice to an e-cigarette solution that either contained nicotine or was nicotine-free. The result with either solution was not only loss of the endothelial cell barrier, but also lung inflammation and an impairment of cell growth, a sign of cell stress. It’s just a short-term lab study, to be sure, but if sustained, that kind of damage is associated with risk for lung diseases such as asthma and chronic obstructive pulmonary disease (COPD).

Note that it wasn’t just the nicotine that caused harm in the study, either. Even the nicotine-free e-cigarette solutions were found to include lung-harming substances, such as the compound acrolein. This substance, which is present in e-cig vapor, damages the endothelial cells in the lungs.


Such short-term lung damage might be acceptable if we knew that e-cigs help people quit smoking. Some studies have found that they do…others have found they are no help at all.

To be fair, there’s no question that vaping is less harmful than inhaling cigarette smoke, which is one of the most toxic substances that humans have ever come to use regularly. Even the biggest opponents of e-cigarettes acknowledge that. So if you switch from smoking cigarettes to vaping e-cigarettes, you’re likely doing less harm to your lungs. If doing so helps you quit entirely, that’s a win-win. (For the best ways to quit, see Bottom Line’s Quit Smoking: 13 Ways That Really Work.

But don’t fool yourself into thinking that vaping is a safe alternative to tobacco. It harms you. And if your children or grandchildren who don’t smoke cigarettes think that vaping is a cool and safe habit to pick up, let them know that they’re playing with addictive electronic fire.