In brief

The study was retracted.

It should no longer be used as evidence.

That does not mean every cancer-risk question is answered. It means this specific study was not reliable enough.

Sometimes only the headline of a study remains in public memory. “E-cigarettes and cancer” is exactly that type of topic: emotional, health-sensitive and easy to oversimplify. A 2022 paper was widely discussed in this context, but was later retracted by the World Journal of Oncology.

That is more than an academic detail. When a study is retracted, it should no longer be treated as reliable evidence in a public debate. This matters especially in health topics, where a weak or flawed analysis can quickly become a strong public claim.

The original paper analysed data from the US NHANES survey and aimed to assess a relationship between e-cigarette use and cancer prevalence. Such datasets can be useful, but they have limits: they often show associations, not automatic causes.

That distinction is important. If people with cancer report different histories of nicotine-product use, it does not automatically mean that the e-cigarette caused the disease. A serious interpretation would need to clarify what came first: use, diagnosis, previous smoking, other risk factors or dual use.

The journal’s retraction notice raised several central concerns: methodology, processing of source data, statistical analysis and the reliability of the conclusions. It also stated that the authors did not provide sufficient explanations and evidence for the questions raised.

That is serious. A study on a sensitive topic such as cancer cannot simply present a striking number. It has to show that the data were processed correctly, that confounding factors were handled appropriately and that the conclusion does not claim more than the data can support.

The retraction does not mean that e-cigarettes are automatically risk-free. That would be just as incorrect as exaggerating the original study in the opposite direction. E-cigarettes may contain nicotine, are not suitable for non-smokers, young people, pregnant people or breastfeeding people, and long-term health questions continue to be studied.

The retraction only means this: this specific publication should no longer be used as a basis for claiming that e-cigarettes cause cancer or prove a particular cancer risk.

A 2025 systematic review reached a cautious conclusion. In the available human studies, no significant incident or prevalent risk of lung cancer or other cancers was found among current vapers who had never smoked. At the same time, biomarker, cell and animal studies point to biological mechanisms that could be relevant for cancer risk.

That is exactly the kind of sentence that rarely fits into a headline: there is no simple final answer. Direct long-term human data remain limited because e-cigarettes are relatively new products and cancers often develop over long periods. At the same time, “not definitively proven yet” is not the same as “harmless”.

Many people do not read the study itself. They read a report about it. If the original report was dramatic, that is often the version that remains in memory. The later retraction receives much less attention.

Health topics therefore need more than a simple yes or no. A better reading asks: Is the study still valid? Which data were used? Was previous smoking considered? Does the study examine e-cigarettes alone or dual use? Was an association found, or was causation proven?

For non-smokers, the position is clear: e-cigarettes are not a product to start using. They are not suitable for young people, pregnant people or breastfeeding people. For adult smokers, the key question is different: how can risks be understood without confusing tobacco smoke, nicotine, e-cigarettes and individual studies?

A retracted study does not help answer that question. It does show how important scientific quality, transparent methodology and cautious language are.