Nicotine-free vapes still harm blood vessels, new study finds

A recent study finds that vaping without nicotine still negatively impacts vascular function—suggesting it’s not a harmless habit, especially for young people and non-smokers.

Many people turn to vaping as a safer alternative to smoking, especially when it comes without nicotine. But a new study shows that even nicotine-free e-cigarettes can impair blood vessel function, which may raise the risk of heart disease over time.

The findings challenge the common belief that vaping is safe if you avoid nicotine. Researchers found measurable vascular harm from all types of inhaled products: traditional cigarettes, nicotine vapes, and even nicotine-free vapes.

E-cigarettes work by heating a liquid—usually made of propylene glycol and vegetable glycerin—into a vapor that users inhale. These ingredients are considered safe to ingest but behave differently when inhaled.

Once heated, they can break down into substances that irritate the lungs and airways. According to experts, this can lead to symptoms like chronic coughing, breathing difficulties, and inflammation.

The flavorings that attract many users, particularly teens, pose another concern. Some contain chemicals like:

• Diacetyl, which is linked to “popcorn lung,” a serious lung disease
• Benzaldehyde, known to irritate the respiratory system
• Heavy metals, released by the device’s heating coils

Vaping’s growing appeal to youth

According to Johns Hopkins, over 2 million middle and high school students in the U.S. reported using e-cigarettes in 2021—and most of them chose flavored versions. Dr. Michael Blaha from Johns Hopkins Medicine warns that many of these users are teens who would never have smoked in the first place.

“It’s one thing if you switch from cigarettes to vaping,” Blaha said. “It’s quite another to start using these products with no prior smoking history.”

Study compares nicotine-free and regular vapes

The new study aimed to find out whether vaping’s health risks came only from nicotine. Researchers compared three groups:

• People using traditional cigarettes
• People using nicotine vapes
• People using nicotine-free vapes

All three showed reduced blood vessel function, a sign of cardiovascular stress. While nicotine vapes had the most pronounced effects, even nicotine-free options weren’t far behind.

“This study shows that the base liquids and flavorings can cause vascular changes,” said Dr. Marianna Nabbout, one of the study’s authors. “If even a single use can affect blood vessels, then regular use could lead to long-term damage.”

If you’re vaping because it seems like a safer choice, this new research suggests caution. Even without nicotine, the chemicals in vape juice—and the act of inhaling them—can still harm your body in ways we’re just beginning to understand.

Vaping may feel harmless, especially without nicotine. But science is beginning to reveal that what we breathe in today could have serious consequences tomorrow.