E‑cigarettes have long been marketed as a safer alternative to traditional smoking, but the results of a three-year University of Alberta study suggest vaping may actually be more harmful.

“We now know that early-life exposure to toxins can impair lung growth and predispose people to future lung disease,” said Michael Stickland, a researcher and professor of pulmonary medicine at the University of Alberta.

He’s part of a U of A team that studied 20 e‑cigarette users in their early 20s over about three years. None had previously smoked traditional cigarettes or marijuana.

During the study, participants underwent a series of cardiovascular stress tests.

“We had them exercise at an intensity equivalent to a moderate walk, and yet they reported much greater breathlessness than you’d expect in a 22- or 23‑year‑old,” he said.

While standard clinical lung tests did not show abnormalities, Stickland said more detailed analysis revealed subtle but important reductions in blood flow and exercise tolerance.

“What was quite surprising is these 23‑year‑old individuals had normal lung function, yet they showed marked exercise intolerance and greater breathlessness,” he said.

Researchers found early lung impairments, including reduced blood flow, as well as heart dysfunction that could lead to more serious complications in the future.

It’s alarming data in light of about one million Canadians vaping regularly, Stickland said.

“Teens and young adults who don’t normally use traditional cigarettes are now vaping or using these electronic cigarettes,” Stickland said.

While the human body reaches its maximum height in the late teenage years, other parts continue to develop into early adulthood. Stickland said the lungs do not fully mature until about age 25.

Researchers also found damage appeared much sooner than would typically be seen in cigarette smokers.

“I’m a dad of two teenagers, and when I saw this, I was quite concerned,” Stickland said.

“It was the first time in my career where I said we really have to keep [studying the effects], because the level of impairment we saw in their blood flow and exercise was concerning and suggested important changes in the lungs that we need to understand better.”

The University of Alberta team is now partnering with researchers at the University of British Columbia on a larger study to track e‑cigarette use and lung function over three years.

“Locally, we’re also going to study blood flow in the lungs to try to understand what’s changed and what might lead to more serious lung disease in the future,” Stickland said.