Pot smokers have been claiming it for years, from the hemp-necklaced throngs at Phish concerts to the vaporizing-intellectuals of the Upper West Side. And now there’s a study to prove it. Smoking pot is better than smoking tobacco—and it might even improve your lung capacity.

Conducted by the University of Alabama Birmingham and U.C.–San Francisco, the study followed more than 5,000 people for 20 years, in part due to a growing interest in medicinal uses for the Schedule 1 drug. Results, now published in the Journal of the American Medical Association, suggest that FEV and FVC, the amount lungs can draw in and exhale respectively, was not impacted negatively by toking up. In fact, sometimes smoking marijuana improved lung capacity. Reason? NPR lays it out:

“That may be due in part to the stretching involved in the deep tokes typical of marijuana use.”

Deep tokes, folks. But where’s the bad news, you ask? There is some. If you have lived more than 10 “joint years,” aka a joint a day for a decade, and smoked pot more than 20 times a month, your lung capacity decreased. Of course, not smoking anything is no doubt much better for you. But potheads, you can dust off that giant bong now if you want to.