According to a new government-funded study, smoking weed–even for years on end–“does not impair lung function,” the New York Times reports. Researchers followed over 5,000 people through the course of twenty years and discovered that “regularly smoking marijuana–the equivalent of up to a joint a day over seven years–did not impair performance on a lung function test.” In fact, those studied often performed better than regular tobacco smokers.

My first reaction to this news was incredulity. After all, anyone who’s smoked cannabis can tell you the immediate effects include coughing. Some stoners have even reported vomiting due to coughing so much. For asthmatics (like myself,) smoking anything can lead to shortness of breath and creates a greater risk of irritated airways.

But think about how we smoke pot: Unlike cigarettes, a hit of marijuana is held in the lungs for an extended period of time. (Most proponents say seven to ten seconds is a desirable length, but that’s much longer than one holds in a puff of tobacco smoke.) The New York Times article brings this up: “[This] may merely reflect marijuana smokers’ years of ‘training’ in taking deep inhalations and holding the smoke, the researchers said.”

Indeed, having that kind of “practice” at holding your breath might help you on a lung performance test. But a big reason these findings matter is that they show that marijuana smoke is better for your lungs than cigarette smoke–and not just because of how long you hold the hit. THC has anti-inflammatory effects, which–as Dr. Donald Tashkin, a pulmonologist at UCLA (not involved in the study,) told the New York Times–may be why cannabis smoke isn’t as harmful as that of tobacco.

That said, don’t expect a lifetime of lighting up to improve your lung function. The researchers found that it worsens with heavier use of marijuana. And if you smoke both pot and cigarettes, it’ll only get worse.

See an abstract of the study or read the full report at the Journal of the American Medical Association.

Austin Wulf is a freelance writer and cannabis activist. Read more of his THC-infused coverage of the pot industry. Want more updates? Follow @Cannabytes303 on Twitter.