For years, vaping has been marketed as a safer alternative to smoking cigarettes. Many people have made the switch, convinced that e-cigarettes—especially nicotine-free ones—are harmless. But a new study is challenging that belief, showing that even vaping without nicotine can negatively impact vascular function, raising the risk of heart disease and circulation problems.

Why People Turn to Vaping

Traditional cigarettes contain thousands of harmful chemicals, including tar and carcinogens that damage the lungs and increase cancer risk. By comparison, vapes eliminate tobacco and tar, which is why they’re often seen as the “healthier” choice. But healthier doesn’t mean harmless. Researchers now warn that vaping introduces its own set of risks—even if the e-liquid contains no nicotine at all.

How Vaping Works

E-cigarettes, commonly known as vapes, are battery-powered devices that heat a liquid to create an aerosol, or vapor, that users inhale. Unlike cigarettes, vapes don’t burn tobacco, so they don’t produce smoke. Instead, they generate vapor from a liquid mixture called e-juice or vape juice.

That juice usually contains propylene glycol and vegetable glycerin, which create the thick clouds users exhale. While both are considered safe to eat, inhaling them is another story. When heated, these ingredients break down into potentially harmful byproducts that can irritate the lungs and airways.

Common health issues linked to vaping include:

• Chronic coughing

• Shortness of breath

• Lung inflammation

The Hidden Dangers of Flavorings

Part of vaping’s popularity comes from the wide variety of flavors available—everything from fruity blends to mint to dessert-like tastes. But flavorings often contain toxic chemicals. For example:

• Diacetyl: Linked to “popcorn lung,” a serious lung disease that causes scarring of the airways.

• Benzaldehyde: A flavoring agent that can irritate the respiratory system.

• Heavy metals: Vape coils can release trace amounts of nickel, lead, and tin into the vapor.

Even when nicotine isn’t present, users are still inhaling these substances directly into their lungs. Over time, that can cause inflammation and long-term respiratory issues.

“You’re exposing yourself to all kinds of chemicals that we don’t yet understand and that are probably not safe,” said Dr. Michael Blaha of Johns Hopkins Medicine.

Vaping’s Popularity Among Youth

Vaping has exploded among teenagers and young adults in recent years. According to Johns Hopkins, more than 2 million U.S. middle and high school students reported using e-cigarettes in 2021, and more than 80% of them used flavored products.

“What concerns me most is that people who never would’ve smoked are now vaping,” Blaha added. “Switching from cigarettes to vaping is one thing. But starting nicotine use through vaping often leads to traditional tobacco down the road.”

What the New Study Found

The latest research looked at whether nicotine-free vaping was truly safe. Scientists compared the impact of three groups:

• Nicotine-containing vapes

• Nicotine-free vapes

• Traditional cigarettes

The results were surprising—and troubling. All three caused measurable negative effects on blood vessel function. While nicotine-containing vapes had the strongest impact, nicotine-free vapes still produced harmful changes in vascular health.

“The decrease in vascular function was most pronounced after inhalation of e-cigarettes containing nicotine, followed by e-cigarettes without nicotine,” the researchers reported.

Dr. Marianna Nabbout, one of the study’s authors, warned that even brief exposure is concerning: “This study highlights the acute effects smoking and vaping can have on multiple vascular systems in the body. If a single session causes immediate damage, it’s reasonable to assume long-term use could lead to chronic vascular disease.”

What This Means for Vapers

If you switched to vaping thinking it was a harmless alternative, these findings should serve as a wake-up call. Even nicotine-free e-cigarettes carry risks, particularly for heart and blood vessel health. And for young people who start vaping before ever smoking, the risks may outweigh any supposed benefits entirely.

The takeaway? Vaping may be less harmful than traditional smoking, but that doesn’t make it safe. Both nicotine and non-nicotine e-cigarettes expose users to chemicals that can damage the lungs, irritate the airways, and now—according to this study—harm vascular function.