Is vaping less dangerous than smoking? The research may not be so clear cut.
Take a recent study, which tested both e-cigarette vapor and cigarette smoke on lung cells and found e-cigarettes to be much less harmful.
In fact, e-cigarettes only damaged the cells when vapor levels were unrealistically high. The study argues that a normal amount of e-cigarette use isn't toxic.
Even though the study was peer-reviewed, some are saying people should take the findings with a grain of salt given who funded the research: A tobacco company that's recently started selling e-cigarettes.
For tobacco brands, it makes sense to get into the e-cigarette industry. Current cigarette smokers — and those who've recently quit — have been more likely to try e-cigarettes.
Besides obvious conflicts of interest, many of the studies have focused on individual medical problems, which are then used to argue the safety of e-cigarettes as a whole.
For example, e-cigs might not damage lung cells, but other research has found the vapor damages DNA, leading to cancer.
While e-cigarettes may reduce some health risks compared to regular cigs, such as lung damage, vaping my actually introduce new health problems.
And compared to regular cigarette smokers, e-cig users have been shown to be at a greater risk for infections and mental illness.
Now is a crucial time for public opinion, though. Americans have been pretty split 50-50 on whether e-cigarettes are safer or more dangerous than regular cigarettes.