While vape companies market their products as safer alternatives to tobacco, “safe” remains a relative term. According to a new study, vaping alone increases the risk of developing lung disease, and smoking tobacco and vaping together increases someone’s chances of getting lung complications far more than if they only smoked or vaped.

The study, published in the American Journal of Preventive Medicine and conducted by researchers at UCSF’s Center for Tobacco Control Research, collected vaping and tobacco use data from 2013 to 2016. The researchers looked at lung disease development in smokers and vapers each year across that three-year period and found that vaping, like smoking, independently increased the risk for COPD, emphysema, asthma, and chronic bronchitis. 

The “independent” part means if smoking and vaping are combined, the chances of getting lung issues later goes way, way up. Consistent with past research, the study also found a greater prevalence of lung diseases in smokers and vapers who had high blood pressure or diabetes.

There’s some good news, though. Subjects who ditched tobacco for vaping reported fewer lung complications by year three, which “suggests that switching from combustible tobacco to e-cigarettes would lower risk of developing respiratory disease,” the researchers wrote. But they also noted later in the paper that vaping is more addictive than smoking tobacco, so take that as you will.

Now, for the study’s main takeaway. By year three, the researchers discovered that about 9 percent of people who only smoked tobacco switched to e-cigs. However, the vast majority of vapers did not stick solely to e-cigs: By the third year, 91.2 percent of e-cig users were also smoking some form of tobacco. 

A separate study on teen vaping discovered that e-cig use among high schoolers has dramatically spiked over the past couple of years, so there’s some legit concern that despite vape companies’ promises to help people quit tobacco, vaping may not do much to curb Americans’ addiction to nicotine.

“E-cigarettes should not be recommended,” the UCSF researchers concluded.

So, stick to weed, homies.

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