Scientists have claimed using e-cigarettes is “far safer than smoking” after analysing the saliva and urine of long-term users for the first time.
They found that people who swapped smoking regular cigarettes for e-cigarettes or nicotine replacement therapy (NRT) for at least six months had “much lower” levels of toxic and cancer causing substances in their body than people who continued to use conventional cigarettes.
For the first time, researchers analysed the saliva and urine of long-term e-cigarette and NRT users, as well as smokers, and compared body-level exposure to key chemicals.
They found that ex-smokers who switched to e-cigarettes or NRT had significantly lower levels of toxic chemicals and carcinogens in their body compared to people who continued to smoke tobacco cigarettes.
However, those who used e-cigarettes or NRT while continuing to smoke did not show the same marked differences, highlighting that a complete switch is needed to reduce exposure to toxins.
Lead author Dr Lion Shahab, senior lecturer in the department of epidemiology and public health at UCL, said: “Our study adds to existing evidence showing that e-cigarettes and NRT are far safer than smoking, and suggests that there is a very low risk associated with their long-term use.
“We’ve shown that the levels of toxic chemicals in the body from e-cigarettes are considerably lower than suggested in previous studies using simulated experiments.
“This means some doubts about the safety of e-cigarettes may be wrong.
“Our results also suggest that while e-cigarettes are not only safer, the amount of nicotine they provide is not noticeably different to conventional cigarettes. This can help people to stop smoking altogether by dealing with their cravings in a safer way.”
Alison Cox, CancerResearchUK’s director of cancer prevention, added: “Around a third of tobacco-caused deaths are due to cancer, so we want to see many more of the UK’s 10 million smokers break their addiction.
“This study adds to growing evidence that e-cigarettes are a much safer alternative to tobacco, and suggests the long term effects of these products will be minimal.
“Understanding and communicating the benefits of nicotine replacements, such as e-cigarettes, is an important step towards reducing the number of tobacco-related deaths here in the UK.”
Commenting on the findings, Professor Kevin Fenton, national director of health and wellbeing at Public Health England said: “This study provides further evidence that switching to e-cigarettes can significantly reduce harm to smokers, with greatly reduced exposure to carcinogens and toxins.
“The findings also make clear that the benefit is only realised if people stop smoking completely and make a total switch.”
“The best thing a smoker can do, for themselves and those around them, is to quit now, completely and forever. E-cigarettes are the most popular quitting method in England and local stop smoking services are the most effective way to give up, with those who combine the two having some of the highest success rates.”
The latest study reflects research published in the British Medical Journal last year, which suggested the use of e-cigarettes was linked to a higher rate of successful attempts to quit smoking in England.
The report estimates that in 2015, use of e-cigarettes helped 18,000 people quit smoking in England.
The latest research is published in full in the journal Annals of Internal Medicine.