Should you listen to TikTok and stop wearing sunscreen? Um…no, say these dermatologists
Viral videos spread fear that isn't based on evidence, dermatologists say
Don't believe everything you see on the internet, say two Newfoundland skin doctors, as videos claiming sunscreen causes cancer go viral online.
It's actually the opposite — that is, not using sunscreen at all — that'll give you a potentially deadly disease.
Skin cancer is the most common type of cancer in Canada, says Dr. Jay Coffey, a dermatologist and associate professor at Memorial University in St. John's.
"About one in five people will develop a basal cell or a squamous cell carcinoma on their face from sun damage," he said.
"The number one risk factor for skin cancer is sunlight."
The viral videos in question, many of them making the rounds on TikTok, are part of an "anti-sunscreen movement" claiming the chemicals found in sunscreens do more damage to the body than they prevent.
But even if any one sunscreen brand happened to be filled with harmful chemicals, twin brother and fellow dermatologist Dr. Joe Coffey argues, the risk of sunlight would outweigh the risk of a topical product.
"Oxybenzone is the chemical being named as the culprit," said Joe Coffey, noting several studies in the past few years that haven't found any evidence the chemical causes cancer.
One study did find abnormalities in rats when the rodents were exposed to "an enormous dose" of oxybenzone — in humans, that dose would translate to 275 years of application to 100 per cent of the body.
"There is no risk that we've seen in any of the studies in Canada over the last three years since this myth came out," said Jay Coffey.
Evidence is clear on risk reduction
The benefits of wearing sunscreen — even in Newfoundland and Labrador, where fog and cloud cover can reign for much of the year — far outweigh the evidence-based risk the pair have seen, they said.
Aside from preventing wrinkles and other signs of aging, it also dramatically reduces the chances of UVB rays penetrating the basal layer of the skin and damaging those cells, raising the risk of cancer.
"Studies done in Australia, where the highest population of melanoma and skin cancer in the world exists, showed that after 15 years of follow-up, there was a 50 per cent reduction in the amount of skin cancers in the group that were being treated with sunscreen," Joe Coffey said.
He pointed out that residents of Newfoundland and Labrador shouldn't shrug off that finding just because they may not see the sun for days on end.
As much as 85 per cent of UV rays can penetrate fog and clouds, as well as windshield glass.
"Our message for Newfoundlanders, because a lot of us are outdoor active people, is to put your sunscreen on daily," he said — even in the rain and snow.
Sunscreen should also be applied several times a day, as its effectiveness diminishes quickly once on the skin. Mineral sunscreens, which use zinc and titanium, tend to last longer, but chemical sunscreens work similarly.
Both are safe according to recent studies cited by the Canadian Dermatology Association, he said.
Download our free CBC News app to sign up for push alerts for CBC Newfoundland and Labrador. Click here to visit our landing page.
With files from The St. John's Morning Show
