Does vaping affect lung function over time?

What “lung function” actually means

When clinicians measure lung function, three things really matter. They look at how much air you can push out, how much your lungs can hold and how easily air moves in and out.

FEV1

How much air you can blow out in one second.

FVC

The total air you can exhale after a full deep breath in.

Airway resistance

How easily air moves through your airways.

What current research shows

A 2022 systematic review pulled together eight studies covering 273 participants. It found that vaping appears to slightly narrow the airways, making air a touch harder to push through. It did not find a measurable drop in FEV1, FVC or the FEV1/FVC ratio.

Your lungs may feel a bit more reactive, but the engine power of your breathing isn't taking a measurable hit in the short term.

The same review flagged an honest caveat. Most of the studies are small. Most ran for a year or less. Widespread vaping has only existed since around 2010, so multi-decade data simply does not exist yet.

Longer studies tracking daily vapers over five years are now underway in the UK and Canada. Full results are still some way off.

A 2024 preliminary study from Quebec following 83 daily vapers picked up some respiratory test abnormalities, even in healthy participants who had never smoked. The researchers were clear these are early findings and bigger studies are needed.

Vaping versus smoking

This is the comparison that matters most to anyone who switched specifically to stay off cigarettes.

The UK government's 2022 expert review concluded that the short and medium-term risks of vaping are a small fraction of those from smoking. Asthma + Lung UK takes the same line.

That does not make vaping harmless. It means the comparison most relevant to former smokers is heavily in vaping's favour. The comparison to never-smoking-and-never-vaping is much less settled.

The chemicals worth knowing about

Vape aerosol still produces some compounds that can irritate the airways.

• Acrolein. A respiratory irritant also produced by cooking and tobacco smoke.
• Formaldehyde and acetaldehyde. Produced when e-liquid is heated, particularly at high wattages or with worn-out coils.
• Diacetyl-related compounds. Banned from UK e-liquids since 2016 under TPD regulations, but occasionally found in non-compliant imports.

Levels are typically far lower than in cigarette smoke, but they are not zero. Burnt or “dry” hits produce significantly more of these chemicals. That is why keeping coils primed and replaced on schedule actually matters for your health, not just the flavour.

Who should be more cautious

Some groups have stronger reasons to think carefully before vaping.

• People who have never smoked. There is no health upside to taking on any new lung exposure.
• People with asthma or COPD. Vape aerosol can trigger symptoms in some, even when it does not cause the underlying condition.
• Pregnant people. The NHS recommends nicotine replacement therapy rather than vaping during pregnancy.
• Under-18s. Illegal to be sold to in the UK. Developing lungs are also more sensitive to airway irritation.

What UK health bodies recommend

The NHS position is consistent. Vaping should be used by adults as a tool for stopping smoking, not as a habit to take up.

Asthma + Lung UK adds an important point. If you have a long-term lung condition, the goal should be to stop vaping eventually. But not before you are ready, since relapsing to cigarettes would be worse.

The bottom line