A new scientific study has raised the prospect that vaping may potentially cause cancer after finding e-cigarette users suffered some similar changes to their DNA as tobacco smokers who develop the disease.
The scientists behind the research, from University College London, are upfront about that fact that their study “does not show that e-cigarettes cause cancer” – but it certainly raises it as a potential risk.
So what did the study show and how worried should vapers be?
What the study found
The research, published in the journal Cancer Research, analysed cheek cells from e-cigarette users and tobacco smokers and found they had “similar” changes to the DNA of cells in their mouth.
These alterations were, in turn, linked to the future development of lung cancer in tobacco smokers as they are thought to allow cells to divide more quickly, potentially growing into tumours.
This finding makes it the first major study to suggest that e-cigarettes could increase the risk of cancer and concluding that “”we cannot assume they are totally safe to use”.
Previous research into the dangers of vaping have tended to focus on risks other than cancer, such as nicotine addiction and impacts on brain development and heart disease, although the risks of these are disputed – and on side effects such as throat and mouth irritation, headache, cough and feeling sick.
But very little research has been conducted into the risk of cancer, as cancer-causing chemicals are generally lower in vapes than cigarettes.
Should vapers be worried?
Scientists, including those involved in the study, agreed that it was far too soon to conclude that vaping may increase the risk of cancer.
But many of those same scientists said it suggested this area of research warranted further investigation and served as a reminder that while vaping is much safer than smoking, it would be better to do neither.
“We cannot say that e-cigarettes cause cancer based on our study, but we do observe e-cigarette users exhibit some similar changes in buccal cells as smokers, and these changes are associated with future lung cancer development in smokers,” said Chiara Herzog, of University College London.
“Further studies will be required to investigate whether these features could be used to individually predict cancer in smokers and e-cigarette users.
“While the scientific consensus is that e-cigarettes are safer than smoking tobacco, we cannot assume they are completely safe to use and it is important to explore their potential long-term risks and links to cancer.”
What do other experts think?
Dr Ian Walker, executive director of policy at Cancer Research UK, which part funded the research, said: “This study contributes to our understanding of e-cigarettes, but it does not show that e-cigarettes cause cancer.
“Decades of research has proven the link between smoking and cancer, and studies have so far shown that e-cigarettes are far less harmful than smoking and can help people quit. This paper does however highlight that e-cigarettes are not risk free, and so we need additional studies to uncover their potential longer-term impacts on human health.”
George Laking, of the University of Auckland, said: “Overall, this paper should not change the basic message of ‘Vaping to Quit.’ Vaping remains an essential tool for harm reduction compared to cigarettes. The question with harm reduction is always ‘by how much is the harm reduced?’ Although that is a question a lot of people are working on, it is not a question this study can answer.”
Professor Andrew Beggs, of the University of Birmingham and University Hospitals Birmingham, added: “This interesting study shows e-cigarette use is associated with similar damaging changes in in human cells as smoking. Although it doesn’t show a direct causal effect, this study shows that further research must be done to understand the effects of e-cigarettes on human health and whether they could be linked to an increased risk of cancer.”
What the study involved
Because vaping is relatively new, little is known about long-term side effects. The researchers say this study is an incremental step in helping researchers to build a deeper understanding of the long-term effects of e-cigarettes on health
It involved data from 4,000 people, and looked at cell samples from hundreds of smokers, as well as vapers who don’t regularly use tobacco.
The study examined the effects on cells by studying a type of epigenetic change in cells called DNA methylation, a chemical reaction in the body in which a small molecule called a methyl group gets added to DNA.
Epigenetics is the term for factors such as our environment, lifestyle and stress, which can modify our DNA, for example by suppressing genes that stop cells dividing into tumours.