A SCIENTIFIC STUDY does not show that sunscreen causes skin cancer despite claims in an influential website in conspiracy theory circles that regularly spreads health misinformation.

The study, which looks into how people’s genes affect their likelihood of developing skin cancer, does discuss the statistical role of sunscreen (also called sun cream) in the data it examines.

But rather than concluding that sunscreen is dangerous, the study notes that its findings “demonstrate the importance of adequate and frequent sunscreen”.

One of the study’s author’s told The Journal that their research had been misinterpreted, and reiterated that sunscreen reduces the risk of cancer.

Nevertheless, false claims citing the study have been spread widely online in recent weeks.

“A major study involving more than 470,000 participants has found that using sunscreen massively increases the risk of three major types of skin cancer,” a deceptive 25 June Facebook post shared more than 1,200 times reads.

The post links and includes a screenshot from an article in The People’s Voice, a website formerly known as NewsPunch that studies have found to be a major spreader of misinformation, 

“Sunscreen shock” the headline of that article reads. “Major study finds melanoma rates nearly quadruples among sunscreen users.”

Like other articles on the website, beneath the headline it says that the article is “Fact checked by The People’s Voice Community”.

As it happens, some of those articles have also been fact-checked by The Journal.

Their previous stories included false claims about countries signing a treaty to “ban natural conception”; Bill Gates microchipping fetuses in the womb to track them when they are born; the World Health Organisation ordering governments into “mega lockdowns” in 2024 over monkeypox; Ireland vowing to arrest people who refuse to take vaccines; and “HIV-infected Green Monkey DNA” being found in Covid-19 vaccines, among others.

The People’s Voice is, in short, an unreliable source of information.

Its article on sun cream begins by saying “A major study involving more than 470,000 participants has found that using sunscreen massively increases the risk of three major types of skin cancer.”

While it miscites the findings, the article does refer to a real paper by Canadian researchers with the not-so-catchy title “Gene-environment analyses in a UK Biobank skin cancer cohort identifies important SNPs in DNA repair genes that may help prognosticate disease risk”.

The paper was published in November 2023, in the journal Cancer Epidemiology, Biomarkers & Prevention, though it is available online through the US government’s National Library of Medicine.

The study looked at data from the UK biobank — an anonymised set of half a million people’s medical data, including their DNA — to see what parts of genes are protective and which are predictive of skin cancers.

The actual results of the paper are about what specific parts of DNA were found to have associations with cancer.

The article in The People’s Voice is based on four mentions of “sunscreen” in the text where it specifically did say that there was a correlation between “frequent” use of sunscreen and skin cancers. This means that people who frequently wore sunscreen were more likely than average to have skin cancer.

The reason we specify that they based it on four of the references to sunscreen is because there were ten in total. And had they read or mentioned the other six, they would have been provided with explanations for this correlation rather than jumping to the conclusion that sunscreen causes cancer.

“This paradoxical finding was the increasing risk of skin cancers with increased sunscreen use,” the paper reads, saying this “can be explained by greater exposure to UV light and/or a lack of reapplication of sunscreen throughout the day, or due to increased use of sun protection following skin cancer diagnosis.”

In other words, people who have already been diagnosed with skin cancer are more likely to use sunscreen. As too are people who are out in the sun a lot, though they may not be using it enough to benefit from its full protection.

“Collectively, however, these findings demonstrate the importance of adequate and frequent sunscreen use and minimization of exposure to UV light, particularly in individuals with fair skin,” the paper notes.

The paper also found that the number of lifetime sunburns was one of the “most important risk factors” for basal cell carcinomas (the most common form of skin cancer) and melanomas (the most deadly kind).

“The post misinterpreted the results of our study,” Dr Ivan Litvinov, Associate Professor at McGill University’s Department of Medicine and one of the study’s authors, told The Journal. 

“The proper use of sunscreen, combined with other sun-protection measures, reduces the risk of skin cancer. This has been clearly demonstrated in studies, and we can see the benefits reflected in the excellent public health outcomes achieved in Australia.”

The seemingly paradoxical finding from observational studies that people who use sunscreen can be more likely to have skin cancer is well documented in research literature.

An analysis of these studies notes that this finding reverses in more rigorous studies, such as randomised controlled trials — experiments where people are, for example, assigned to wear or not wear sunscreen to see what its effects are (the sunscreen users got less cancer).

This analysis also notes that people with fair skin are more susceptible to skin cancers. However, because those people are more likely to get sunburnt, they are also more likely to wear sunscreen when they go out.

So pale people are more likely to get skin cancer, and to use sunscreen, but this does not mean sunscreen causes cancer.

“When sunscreen is used as a ‘permission to tan,’ problems arise,” study author Dr Litvinov said. “Many people apply less than the recommended amount, fail to reapply it appropriately, and develop a false sense of security.

“As a result, they spend more time in the sun without employing other protective measures, leading to increased tanning and sunburns, while having a false sense of protection.

“Ultimately, this can result in greater cumulative UV damage and a higher risk of skin cancer among individuals who report using sunscreen ‘regularly.’ This phenomenon forms the basis of the so-called ‘sunscreen paradox‘,” Litvinov wrote

The HSE recommends the use of sunscreen to protect against harmful radiation from the sun, noting that it should be reapplied every two hours (or sooner if you are sweating).

There is an abundance of data, including in the UK Biobank indicating that sunburns can cause long-term health effects and increase the risk of future skin cancers

The Journal has previously debunked other claims about sunburn, including that it cooks your skin, contains toxins, or causes cancers by blocking the production of vitamin D

The Journal has also investigated claims over the health effects of sunbeds, including whether all the research connecting their use with cancer was outdated (it’s not).

The Journal’s FactCheck is a signatory to the International Fact-Checking Network’s Code of Principles. You can read it here. For information on how FactCheck works, what the verdicts mean, and how you can take part, check out our Reader’s Guide here. You can read about the team of editors and reporters who work on the factchecks here.