E-cigarettes have been shown to be safer than smoking in a new long-term study carried out by Cancer Research UK.

Public Health England responded to the study, which was published in February, saying this was 'further evidence' of the benefits of swapping cigarettes for vaping.

The study saw researchers analysing saliva and urine of long-term e-cigarette and nicotine replacement therapy (NRT) users for the first time, comparing body-level exposure to key chemicals.

They found that former smokers who completely switched from cigarettes for six months had significantly lower levels of toxic chemicals and carcinogens compared to those who continued to smoke cigarettes. They also found that for those that did not completely swap out cigarettes, the difference was less marked.

Dr Lion Shahab, senior lecturer in the department of epidemiology and public health at UCL and lead author of the report, said: '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.'

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.'

But the study did not clear all doubt over vaping, coinciding with a recently published paper in JAMA Cardiology, which found e-cigarette users had increases in biochemical markers associated with heart disease, suggesting they still put people at heightened risk compared with people who neither smoke nor vape.

This article was originally published in Pulse