We came across the posts on the following topic on the social media platform X (1, 2):

The posts contain a clip of man speaking about a link between the use of sunglasses and the risk of cancer.

He claims that by using sunglasses, people filter out some of the spectrum of light. The light that is filtered out, including light in the ultraviolet spectrum, is essential for the production of a hormone in the brain that in turn stimulates production of melanin in the skin, he says. He claims that without sufficient melanin, people become susceptible to skin cancer from sunlight.

Controversial Opinions

As the videos did not include the identities of the creator or the speaker, we conducted a reverse image search using a screengrab of the video. The search did not reveal the origin of the video, but we were able to identify other posts including the video on Facebook and Instagram, including on accounts that were ostensibly related to matters of ‘wellness’ and health tips.

On one of these posts, we found an attribution of the claims to a man named Andreas Moritz (misspelled as Mortiz by the post). While web searches of the name turned up few results in terms of information from credible sources, we found a short bio on the page of an organisation that appears to have been created by Moritz, as well as a Wikipedia page in the Norwegian language.

Using a combination of information from the two sources, we found that Moritz was a practitioner of alternative or ‘natural’ medicine who had several controversial opinions on health and medicine that ran contrary to conventional and scientific understanding. These opinions were contained in the many books written and published by Moritz.

For example, Moritz believed that cancer was not a disease but an attempt by the body to heal itself, and that undergoing treatment such as chemotherapy to treat it was the true cause of the illness and death. He was also a vaccine sceptic, publishing a book that likened it to ‘poisoning the population’. Multiple sources state that Moritz died in 2012.

Similar Ideas Circulating and Debunked Previously

When we looked up the link between the use of sunglasses and cancer, we found that similar claims to that expressed by Moritz had been circulating on social media prior to the posts on Moritz, which appear to have been circulating mostly from August 2024 to more recently.

The earliest report addressing the claims of a link were in a factcheck by the Irish news publication The Journal in 2021 of viral social media posts. While the Journal did not appear to reference the clip of Moritz, the ideas discussed in the posts were identical.

The Journal traced the ideas back to a book published in 2007 called ‘Survival of the Sickest’ by Sharon Moalem and Jonathan Prince. The book suggested, as Moritz does, that ‘wearing sunglasses could be linked to growing levels of skin cancer because they stopped the body from receiving signals that would cause it to protect itself in the sun’.

The Journal was able to trace an academic review of the book from 2008 that said it contained some errors along with ‘unsubstantiated hypotheses’.

The Journal also pointed out that there was no advice from public and international health organisations, such as the World Health Organisation, to avoid wearing sunglasses. On the contrary, several organisations recommended wearing sunglasses to protect the eyes against sun damage, as well as lower the risk of skin cancers in the area around the eye.

The Journal’s findings were corroborated by AFP Fact Check, which separately conducted its own investigation following the emergence of viral posts in 2023 on YouTube, Instagram, TikTok and Twitter (now X).

Though the posts once again did not include the clips of Moritz, the claims were identical and were found to be false. AFP Fact Check pointed out that skin cancer is strongly associated with excessive sun exposure, and interviewed experts who said that the only risk from using sunglasses were if wearing them incentivised someone to stay outside in the sun longer.

Skinning the Facts

False social media posts misattributing the causes of cancer, including skin cancer, are not uncommon. Black Dot Research has previously published a factcheck on a claim that falsely attributed skin cancer to the use of sunscreen lotion.

As with that claim, the claim linking the use of sunglasses and skin cancer is false and harmful. There is no evidence that using sunglasses increases the risk of cancer. On the contrary, they are recommended by experts as a tool to help reduce the risk of cancer and other health issues.