If you smoke marijuana, or vape e-cigarettes, you could end up with the kind of damage to your lungs and airways that could put you at risk of real harm from COVID-19, medical experts said.

Inhaling smoke and vapors brings foreign substances into the body, puts acute stress on the lungs, creates long-term damage to the body, and can hurt the immune system — a bad mix at any time, and especially during a global pandemic of a respiratory disease.

“What we worry about is impaired function and the risk of infection,” said Brenda Douglass, the director of Drexel University’s Doctor of Nursing Practice program and a professor in its College of Nursing and Health Professions. “We do really worry about someone who smokes cigarettes or vapes … is there a greater propensity with smoking and with vaping for COVID-19? I would think so.”

From the beginning of the crisis, there was the worry from medical professionals that smokers with impaired lung function may be more at risk of problems with COVID-19, but there were still questions. So people asked us: Why? Does marijuana use count? What about vaping, since there’s no combustion? How serious is the risk? And is it too late if I’ve been smoking or vaping for years?

Why this question is tricky to answer

But answering the questions isn’t easy. The reason, Douglass and other experts said, is that the coronavirus is so new that we just don’t have a strong body of research yet. And given the way scientific knowledge is built over years, even vaping doesn’t have a lot of research around it compared with the decades of study on tobacco use. Still, their advice around smoking tobacco cigarettes generally also applies to smoking marijuana, they said, because of similar concerns around lung damage, as well as to vaping.

(Note: While we spoke with several medical experts for this article, this is not specific medical advice, which should come from your health-care provider. And this pertains to social and recreational smoking and vaping, not medical uses of marijuana.)

But while there are few definitive answers, the experts said, it’s best to err on the side of caution and make reasonable judgments based on existing knowledge.

For example, experts agreed with the World Health Organization that just the act of smoking can increase the risk of infection.

“Smokers are likely to be more vulnerable to COVID-19 as the act of smoking means that fingers (and possibly contaminated cigarettes) are in contact with lips which increases the possibility of transmission of virus from hand to mouth,” the organization says.

Another reason: Smoking marijuana is often a social activity, which is also, obviously, risky, said Andrew Berman, a professor at Rutgers University’s New Jersey Medical School and director of its division of pulmonary and critical care medicine, which is combined with allergy and rheumatology.

“What that does is promote recurrent connections with your hands to your mouth, other people’s germs from them to you,” he said. “And so the whole sort of community behavioral aspect of smoking marijuana is potentially harmful with COVID-19.”

But even if you smoke alone, experts said, smoking and vaping can damage the lungs and airways in ways that can make you more vulnerable if you do become infected. Even if you are just smoking a little to help you relax, it’s probably a better idea to find some other way to relieve stress right now, experts agreed.

“Smokers may also already have lung disease or reduced lung capacity which would greatly increase risk of serious illness,” the WHO says.

Inhaling smoke is damaging to the lungs and cardiovascular system, and can reduce your lungs’ ability to exchange oxygen, said Andrew Strasser, a professor at University of Pennsylvania’s Perelman School of Medicine and director of its Penn Tobacco Center of Regulatory Science.

That’s why smokers tend to develop shortness of breath and chronic obstructive pulmonary disease, he said.

“After years of smoking you already have damage. Now you’re introducing this whole extra challenge to your system with a viral [disease],” said Strasser.

Damage your body’s defenses

Smoking and vaping may also affect your immune system, Berman said.

And right now, we want our body’s defenses in peak condition.

“We’re dealing with this virus that is putting so much chaos into the world that any little thing we can do to take control is what we should do,” he said. “And certainly doing anything to protect your lungs’ immune system should be pretty high up there.

The good news, the experts said: Quitting now can help.

First and foremost, quitting smoking and vaping prevents further damage. The harm done to the body can compound over time, so stopping at any time can have significant benefits.

And while some damage will take a long time to repair, if ever, other changes begin to happen immediately, said Larider Ruffin, a nursing professor at Stockton University who teaches about smoking and marijuana.

“It’s going to take some time for the lungs to fully repair, but if you are smoking right now, I would tell you to stay away," Ruffin said. It’s not easy, and people who trying to break an addiction should contact their health care provider, he said, but it will help both now and in the long run.

“Any little time it takes you that you are not [smoking], you are not vaping, that will add some levels of protection," he said. “Bottom line is, try your best to stay away from smoking.”