"What we found is that for e-cigarette users, the odds of developing lung disease increased by about a third, even after controlling for their tobacco use and their clinical and demographic information," senior author Stanton Glantz said in a statement. "We concluded that e-cigarettes are harmful on their own, and the effects are independent of smoking conventional tobacco."

A particularly high risk was found among people who combined both conventional cigarettes and vaping. This exposes users to the risks from both activities which multiply each other, meaning that smoking and vaping together is actually more dangerous than just smoking.

This is a problem for the vape industry, which has marketed itself as a way to reduce tobacco use. If people are trying to quit cigarettes and are switching to vapes, they are at a higher risk of lung disease if they continue to smoke occasionally as well.

These risks are on top of the recent spate of lung diseases caused by EVALI (e-cigarette, or vaping, product use associated lung injury), and the risks from contaminated vape pods.

Overall, the evidence is not looking good for the health effects of vaping. "This study contributes to the growing case that e-cigarettes have long-term adverse effects on health and are making the tobacco epidemic worse," Glantz concluded.