Studies
We now have over a decade’s worth of toxicological, clinical and behavioural data on vaping products. This rich and varied literature provides a strong scientific basis to determine vaping’s safety relative to smoking and its utility to a smoker looking for a better alternative. We have collected some of that data here.

Cochrane review: High certainty evidence nicotine e-cigarettes help more people to quit than NRT
Nicotine e‐cigarettes can help people to stop smoking for at least six months. Evidence shows they work better than nicotine replacement therapy, and probably better than e‐cigarettes without nicotine.
“They may work better than no support, or behavioural support alone, and they may not be associated with serious unwanted effects.”

Vaping helps reduce smoking in patients with severe mental illness – 24 week pilot study
Smoking is the largest single contributor to poor physical health and increased mortality in patients with severe mental illnesses. This study from Kings College London looked at a small population of smokers with psychotic disorders. Within six weeks, there was a >50% reduction in cigarettes smoked per day

Randomized control trial shows smokers more likely to quit with vaping products
A randomized control trial, published in the New England Journal of Medicine, randomly assigned visitors to a stop smoking clinic to either nicotine replacement therapy of their choice or a vaping product of their choice. Twice as many in the vaping products were cigarette abstinent after one year than in the NRT group.

Royal College of Physicians seminal 2016 report on nicotine without smoke
The Royal College of Physicians – the pre-eminent physicians organisation in the United Kingdom – updated its members on the use of harm reduction in tobacco smoking. It shows that harm reduction has “huge potential” to prevent death and disability from tobacco use. It suggests that vaping products cause less than 5% of the harm from smoking.

Dependence on vaping products examined in a cross sectional study of adults in the United States
This study, supported by the University of Pittsburgh, looked at government data from the United States, where regular tobacco use surveys are undertaken. The analysis showed that among current users of both products, dependence on vaping products was significantly lower than dependence on cigarettes

Incorrect perceptions of the relative harm from vaping compared to smoking getting worse
Researchers from a variety of US universities reviewed the data from two multi-year cross sectional surveys that took place from 2012-2017. The proportion of US adults who perceived vaping to be as harmful as or more harmful than cigarettes increased substantially. The findings of this study underscore the urgent need to accurately communicate the risks of e-cigarettes to the public, which should clearly differentiate the absolute from the relative harms of e-cigarettes.

Significant improvement observed in former smokers who switched completely to vaping
In this prospective randomized control trial, participants who smoked but were free from cardiac disease were provided with vaping products. Within one months of switching to vaping, there was a significant improvement in endothelial function and vascular stiffness. There was no difference in vascular effects between those who used vaping products with nicotine and those without.

Independent Scientific Committee on Drugs ranks nicotine products in order of harm
An international and inter-disciplinary expert panel convened by the UK government used a multi-criteria decision making model to determine the relative harms of different forms of nicotine use. It concluded that attempts to switch to non-combusted sources of nicotine should be encouraged as the harms from these products are much lower.

Cancer potencies of emissions from e-cigarettes are 99 % lower compared with those of tobacco smoke.
How exactly is the damage potential of e-cigarettes compared to tobacco products? This Scottish examination provides clear evidence for the topic of harm reduction with the e-cigarette.

E-cigarettes emit much lower amounts of toxic compounds compared to tobacco cigarettes and also Heated Tobacco.
Due to the combustion, tobacco smoke contains around 7,000 chemical compounds, 250 of which are toxic and 70 are carcinogenic. Vaping significantly reduces the number of toxic pollutants.

Respiratory symptoms are much lower among e-cigarette users than among smokers.
This study examines the effects of vaping on the respiratory system. Compared to smoking, the e-cigarette offers a great harm reduction potential.

PHE publishes independent expert e-cigarettes evidence review
Landmark study finds that health risks associated with e-cigarette usage are 95% lower than those related to smoking tobacco, while risks of developing cancer are found to be only 0,5% of the risk related to tobacco cigarettes.