No, sunglasses do not raise the risk of sunburn—but exposure to the sun does, and it can cause cancer

Last month a widely liked post on Instagram, and a similar post on Facebook with more than 1,700 shares, claimed that wearing sunglasses raises the risk of sunburn and that the sun does not cause skin cancer.

Both of these claims are false, and we have written about similar claims before. In fact about 90% of UK melanoma skin cancer cases could be prevented if people stayed safe in the sun, and avoided sunbeds.

These posts come from a UK-based influencer called Ellie Grey, who has around 200,000 followers on Instagram and who we have also fact checked before. Both posts make a number of other claims about a wide range of medical topics. This fact check only considers the claims about sunglasses and sunburn.

False information can be dangerous if people use it to make decisions about their health.

Full Fact approached Ms Grey for comment by email. At the time of writing she has not replied to us, but she has posted a copy of our email on Instagram and Facebook, saying in a caption: "Every single one of my posts has the sources which include peer reviewed medical journals." We could not find any sources mentioned in the posts we asked about, however.

Sunglasses do not make you more likely to burn

Ms Grey’s Facebook and Instagram posts both said: “Sunglasses make you more likely to burn. Blocking UV signals to the eyes disrupts melanin production, which helps the skin adapt to sunlight.”

As we explained in our previous check on this subject, melanin is a pigment that affects the colour of people’s skin. It is produced locally in response to sunlight to protect the affected areas from further damage.

This is why people can develop tans on the parts of their skin that were exposed to the sun, but not on the areas that were covered up. Wearing sunglasses therefore might reduce the chance of burning on the skin immediately around the eyes, which they are covering, but it will not affect the chance of burning or tanning anywhere else on the body—as seen in the use of eye protection in tanning salons.

Far from being harmful, sunglasses verified to filter out UV rays can protect your eyes from the sun, and are recommended by the NHS when the sun is strongest, which in the UK is between 11am and 3pm between March and October. 

Sunlight does cause skin cancer

The Facebook and Instagram posts also said: “The sun doesn’t cause skin cancer - chemical sunscreens and diet do.” And this is also not correct.

While skin cancer may take a long time to develop, and the risk may be influenced by a range of factors, the NHS clearly says that “sunburn increases your risk of skin cancer”.

This is because certain types of radiation within sunlight can damage the DNA in skin cells, potentially leading to genetic changes that might cause cancer. Cancer Research UK says that almost 9 in 10 cases of melanoma skin cancer in the UK “could be prevented by staying safe in the sun and avoiding sunbeds”.

The NHS recommends using sunscreen to stay safe in the sun. And as we said in a previous fact check, there is good evidence that sunscreen use reduces the risk of skin cancer. 

Regarding the claim linking chemical sunscreens to skin cancer, we published a fact check in 2023 explaining that benzene, a known cancer-causing chemical, is not generally an ingredient in sunscreen, and while some sunscreen has been found to be contaminated with benzene, in most cases this is not in harmful quantities. We published another shortly afterwards on why the evidence shows that sunscreen lowers the risk of skin cancer.

Some chemicals present in some sunscreens, including oxybenzone, have been investigated to establish whether using them normally may be bad for people’s health. There isn’t enough evidence to say that no sunscreen ingredient has any harmful effects, but sunscreens on sale in Great Britain must show the Office for Product Safety & Standards that they are “safe for human health under normal and reasonably foreseeable conditions of use”.

As for diet, it is true that eating healthily can lower your risk of cancer, and some studies have suggested links between specific foods and drinks and skin cancer. For instance, a 2022 study found an association (not necessarily a causal link) with eating more fish and a higher risk of melanoma, but scientific experts described a number of limitations in this study in their comments to the Science Media Centre at the time. Sun exposure is a well established risk, by comparison.