Does Vape Damage Your Lungs?

Vaping can have negative effects on the lungs, though the full extent of long-term harm is still being studied. Here’s what the current evidence shows:

What happens to the lungs when you vape?

Inhalation of chemicals – E‑liquids typically contain propylene glycol, vegetable glycerin, flavorings, and nicotine. When heated, these can break down into potentially harmful compounds, such as formaldehyde, acrolein, and diacetyl, which are known to irritate the airways and contribute to lung damage.

Inflammation and irritation – Studies show that even nicotine-free vapor can cause airway inflammation and impair the function of cells that line the lungs. This may reduce the lungs’ ability to clear out pathogens and debris, making users more susceptible to infections.

Reduced lung function – Some research has observed short-term decreases in measures like forced expiratory volume (how much air you can forcibly exhale in one second) after vaping, although these changes are generally less severe than those seen with traditional cigarette smoking.

EVALI outbreak – In 2019–2020, a wave of severe lung injuries in the United States (EVALI) was strongly linked to vaping products containing vitamin E acetate, often used in illicit THC cartridges. While this was not caused by standard nicotine e‑liquids, it highlighted that certain additives can be extremely dangerous.

How does it compare to smoking?

Most public health authorities, including the Royal College of Physicians and Public Health England, estimate that vaping is likely 95% less harmful than smoking combustible cigarettes. However, that does not mean vaping is safe. The long-term risks, especially from daily use over decades, are not yet known.

Who is most at risk?

Never-smokers – People who have never smoked and take up vaping expose their lungs to unnecessary risk.
Youth and young adults – Developing lungs are more vulnerable to damage, and nicotine can harm brain development.
People with pre-existing lung conditions – Vaping can worsen asthma, COPD, or other respiratory diseases.

The bottom line

For current smokers, switching completely to vaping can reduce exposure to tar and carbon monoxide—the primary culprits in smoking-related lung disease. But for anyone who does not already smoke, the safest choice is to avoid vaping entirely. If you are concerned about lung health, quitting all inhaled products is the most protective step you can take.

This answer is based on current medical evidence as of early 2025, but research is ongoing.