Smoking, vaping weed increases risk of asthma attacks among young adults, study finds

Weed might increase a young person’s risk of an asthma attack, whether or not they are smoking or vaping it, a new study says. Young adults had 57% to 81% higher odds of an asthma attack if they smoked or vaped cannabis, researchers report in the journal Chest.

“Inhaling marijuana products—either smoking or vaping marijuana—was significantly linked to an increased risk of asthma attacks,” concluded the research team led by Dr. Eric Mortensen, chief of general internal medicine at UConn Health in Farmington, Connecticut.

Most weed users in the U.S. are young adults, with 35% of those 18 to 25 using regularly, compared with 22% of those 26 and older, researchers said in background notes.

For the new study, they tracked the health of nearly 4,500 18- to 34-year-olds taking part in an ongoing federal study of tobacco use and smoking. The team tracked weed use and compared it to asthma attacks among the participants.

Results showed that 17% of participants had smoked weed within the past 12 months, 9% had vaped and nearly 11% had done both.

Overall, about 5% of all those surveyed had experienced at least one asthma attack, the study found.

Researchers followed these young adults for a year to see whether weed use was associated with asthma attacks.

Those who smoked weed had a 64% increased risk of asthma attacks, while those who vaped had 81% higher odds of an asthma attack, researchers found. Those who both smoked and vaped weed had a 57% increased risk.

Previous studies also have linked weed to asthma, with some finding the odds of asthma increasing with the more cannabis a person uses, researchers said.

However, other studies have suggested that weed might help asthma, possibly by opening up a person’s airways, researchers said.

This study could not prove a direct cause-and-effect link, but only show an association.

“Given the rising prevalence of marijuana use among young adults and the evolving regulatory landscape of marijuana products, further research is necessary to strengthen the understanding of its long-term effects on respiratory health, especially asthma outcomes,” the team concluded. “Such evidence will be essential for guiding clinicians and shaping public health recommendations.”

Copyright © 2026 HealthDay. All rights reserved.