The UK position. NHS, OHID, Cochrane plus Royal College of Physicians all support vape as harm reduction for smokers. The principle is relative harm reduction from smoking rather than absolute safety. For non-smokers including young people vape is not recommended because it creates dependence risk without meaningful benefit. This article focuses on the smoking-versus-vape comparison rather than questions about whether non-smokers should vape.

The core principle: combustion is the problem

Smoking kills approximately half of long-term users. Understanding why is essential:

Combustion creates thousands of chemicals. Burning tobacco at 900 degrees Celsius produces:

• Tar. Sticky dark material containing dozens of known carcinogens.
• Carbon monoxide. Reduces blood oxygen-carrying capacity.
• Formaldehyde. Known carcinogen.
• Benzene. Known carcinogen.
• Polycyclic aromatic hydrocarbons (PAHs). Multiple carcinogens.
• Heavy metals. Lead, cadmium, arsenic plus others.
• Nitrosamines. Potent carcinogens.
• Particulate matter. Damages lung tissue.
• Thousands more compounds many with unknown long-term effects.

These combustion products cause most smoking disease:

• Lung cancer (from carcinogens in tar).
• COPD (from particulate damage to airways).
• Cardiovascular disease (from CO plus inflammatory effects).
• Other cancers (bladder, kidney, oesophagus plus others).
• Respiratory infections (from immune damage plus mucus disruption).

Nicotine contributes to smoking but nicotine alone at typical exposure levels causes limited direct disease. Cancer, COPD plus most cardiovascular disease come from combustion products. See our nicotine addiction guide for the addictive-but-relatively-safe paradox.

What vape has (and does not have)

Vape contains:

• Nicotine. Same addictive compound as cigarettes. Less direct disease impact than other smoking components.
• Propylene glycol (PG). Pharmaceutical-grade carrier. Generally recognised as safe for oral consumption. Respiratory effects less studied long-term.
• Vegetable glycerin (VG). Pharmaceutical-grade carrier. Similar profile to PG.
• Flavour compounds. Varies by product. UK testing screens for concerning compounds.
• Some thermal degradation products. Low levels of compounds formed when e-liquid is heated including trace formaldehyde at low levels.

Vape does NOT contain:

• Tar (no combustion).
• Carbon monoxide at significant levels.
• Most polycyclic aromatic hydrocarbons.
• Most nitrosamines.
• Most heavy metals at cigarette levels.
• The thousands of other combustion products.

This is the mechanism of harm reduction: same nicotine delivery, most of the harmful compounds removed.

The 95 per cent figure

The “95 per cent less harmful” figure comes from Public Health England 2015 landmark review. Context:

What PHE said:

• “Best estimate” that vape is around 95 per cent less harmful than smoking.
• Based on expert assessment of available evidence.
• Acknowledged uncertainty plus need for further research.
• Recommended vape as harm reduction for smokers.

Subsequent reviews:

• OHID continues to publish vape evidence reviews.
• Generally support the vape-as-harm-reduction position.
• Specific numbers have been discussed plus sometimes debated.
• Broad conclusion consistent: vape substantially less harmful than smoking.

International variation:

• US health bodies more cautious than UK.
• Australian approach different (prescription-only nicotine vape).
• WHO takes more cautious stance than UK.
• Differences reflect regulatory approach plus evidence interpretation not fundamental disagreement about relative harm.

Cochrane Review 2024:

• Systematic review of cessation evidence.
• High-certainty evidence that vape is more effective than NRT for smoking cessation.
• Moderate-certainty evidence on safety.
• Supports vape as cessation tool with appropriate caveats.

The precise percentage is less important than the underlying principle: vape is substantially less harmful than smoking because combustion harm is absent.

Cancer comparison

Smoking is the largest preventable cause of cancer:

• Causes approximately 15 types of cancer.
• Responsible for ~25 per cent of all cancer deaths.
• Main mechanism: carcinogens in smoke cause DNA damage over years.
• Tar plus nitrosamines are main cancer-causing components.

Vape cancer risk:

• Substantially lower than smoking.
• IARC does not classify nicotine itself as a carcinogen.
• Most carcinogens in smoke are absent from vape.
• Trace carcinogens may form from thermal degradation but at much lower levels.
• Long-term cancer risk data not yet available (vape is newer).
• Current evidence: far lower cancer risk than continued smoking.

Our cancer risk guide covers this in detail.

Respiratory comparison

Smoking respiratory effects:

• COPD (chronic obstructive pulmonary disease) – major cause of death.
• Lung cancer.
• Chronic bronchitis.
• Emphysema.
• Respiratory infections more frequent plus severe.
• Reduced lung function over years.

Vape respiratory effects:

• Generally much less damaging to lungs than smoking.
• Can trigger asthma symptoms in some users.
• Some airway irritation particularly in new users.
• Long-term effects over decades not fully known.
• Ex-smokers who switch to vape typically report respiratory improvement.
• Diacetyl (popcorn lung cause) banned in UK since 2016.

Ex-smokers who switch to vape typically see measurable improvements in FEV1 (lung function) plus symptom reduction within weeks to months.

Cardiovascular comparison

Smoking cardiovascular effects:

• Major cause of heart disease.
• Stroke risk doubled.
• Peripheral artery disease.
• Accelerated atherosclerosis.
• Reduced HDL cholesterol.
• Increased inflammation.

Vape cardiovascular effects:

• Less severe than smoking.
• Some short-term blood pressure plus heart rate elevation from nicotine.
• Less inflammation than smoking.
• Carbon monoxide absent so no CO-driven cardiovascular stress.
• Long-term cardiovascular data still developing.
• Ex-smokers who switch typically see cardiovascular marker improvement.

Secondhand exposure comparison

Secondhand smoke is a well-established harm. Secondhand vape exposure:

• Much less harmful than secondhand smoke.
• Contains primarily water vapour plus small amounts of nicotine, PG and VG.
• No tar, CO or most smoke carcinogens.
• Still avoidable for consideration of others.
• Not equivalent to clean air.
• Particularly worth avoiding around children and pregnant women.

Our secondhand vape guide covers this in more detail.

Cessation effectiveness

Beyond harm reduction, vape is a cessation tool:

• Cochrane Review 2024: vape more effective than NRT for smoking cessation.
• Approximately 50-70 per cent higher quit rates vs NRT alone in some studies.
• NHS Stop Smoking Services support vape as cessation aid.
• Part of standard NHS smoking cessation offer.
• Most effective when combined with behavioural support.

Our dependence guide covers this.

Mortality comparison

Smoking kills approximately half of long-term users through:

• Cardiovascular disease (heart attacks, strokes).
• Cancer (multiple types).
• Respiratory disease (COPD, lung cancer).
• Other smoking-related conditions.

Vape mortality:

• No current evidence of significant direct mortality from UK compliant vape.
• Long-term data still developing.
• Expected to be substantially lower than smoking based on mechanism.
• Any future mortality impact likely much smaller than current smoking mortality.

Why full cessation beats switching

Full cessation of all nicotine is cleanest long-term position because:

• Eliminates remaining vape-related risks.
• Removes dependence.
• Cardiovascular effects of nicotine resolve.
• Long-term uncertainty eliminated.
• Financial cost eliminated.

For smokers who struggle with full cessation, switching to vape is a meaningful intermediate step. Some smokers eventually quit vape too. Others stay on vape long-term but with substantial harm reduction compared to continued smoking.

For non-smokers specifically

The harm reduction framing applies to smokers. For non-smokers:

• Starting vape creates dependence risk without meaningful benefit.
• Nicotine itself has some effects (cardiovascular, dependence).
• Long-term vape risks exist even if smaller than smoking.
• UK regulation particularly restricts vape marketing to non-smokers.
• NHS does not recommend vape for never-smokers.

Practical approach

• For current smokers: switching to vape is meaningful harm reduction. NHS Stop Smoking Services support.
• For recent ex-smokers: continuing vape is better than relapse to smoking.
• For long-term vapers: consider step-down toward cessation when ready.
• For non-smokers: do not start vape. No meaningful benefit.
• For minors: UK law restricts sale to 18+ for good reason.
• Full cessation of all nicotine is cleanest long-term position.

For smokers switching to vape, our nicotine salts collection covers every UK compliant strength from 20mg down to 3mg to match current nicotine needs.