SUMMER HAS BEGUN, meaning soaring temperatures (maybe), shining sun (possibly), and weeks of balmy, good weather (probably not).

It’s also a time you’ll hear good advice to wear suncream, but an odd chorus of counter advice has taken hold with false and harmful claims that suncreams can be dangerous.

These include incorrect suggestions that sun scream is full of “toxins”, can block vitamin D or cause cancer.

These claims, which have long been espoused online, came to the fore in Ireland recently in reaction to the appearance of skincare expert Eavanna Breen on TV to talk about the dangers of sun exposure and the importance of wearing suncream.

“I opened a can of worms,” Breen said in a 19 May Instagram video. “People saying in the comments that I didn’t know what I was talking about. That suncreams are full of toxins and we shouldn’t be putting them on our skin.”

Breen is correct. Social media is rife with posts that make false claims about suncream (also called sunscreen), often from accounts that claim to give health advice, can accumulate hundreds of thousands or even millions of views.

Although many of the most popular versions of these posts are not from Ireland their influence has been felt here, particularly in alternative medicine circles.

“It’s this rejection of what they need – man made or synthetic – versus what they deem natural,” says David Robert Grimes, a science writer who studies how misinformation spreads. By way of example, he shows why this belief is false: “Arsenic, Uranium and Ebola are all ‘natural’.”

Grimes conducted research for his PhD into UV radiation, which is what can make sunlight so damaging.

“A tan is your body’s way of screaming at you ‘get me out of the sun’. It is an adaptive response to UV radiation,” he summarises.

“The idea [among those spreading misinformation] is that suncream is made by man, so putting it on your skin is bad, but the sun is natural, therefore it’s good,” Grimes said.

He noted that a similar logic is often used by people who go against vaccines; viruses are natural, while vaccines contain ingredients which are synthetic. Nevertheless, the vaccines in use are much less likely to cause you harm than being infected with the live virus.

Grimes also said that many of these outlandish claims often do well because of social media algorithms, which promote them into people’s feeds.

People who scroll on social media sites are more likely to click on and react to counterintuitive claims, even if it’s to argue against them. On many social media sites, such interactions push those posts higher in the feed so that even more people can see them. 

On the flip side, standard advice can struggle to make an impression; even if it is correct, people have heard it all before.

Anti-sunscream claims tend to fall into three main categories: that suncream is toxic; that suncream does more harm than good by blocking vitamin D production; and that there were no skin cancers in the past before suncream was used.

These claims can be dangerous. UV radiation, such as that from the sun or tanning beds, is the main factor for most skin cancers in Ireland.

There were, on average, 7,545 cases of Basal cell carcinoma and 1,243 cases of melanoma, both types of skin cancer caused by the sun, diagnosed annually between 2018 and 2022. According to an analysis by the National Cancer Registry, rates of both these cancers are increasing.

If people forego suncream, especially if they do so thinking that the sun’s rays must be healthy for them, they are putting themselves at risk needlessly. 

Toxins

One of the major claims made against suncream is that it contains toxic ingredients.

“What if slathering toxic, cancer-causing chemicals on our skin in the name of “protection” was doing more harm than good?” one post we found on Facebook by a skincare company asked.

However, unlike posts by other users that appear to be dispensing odd health advice for social media engagement, the motivation behind that one is clear: it also promotes the company’s own suncream, which it says is made from beef fat and “non-nano zinc”.

(Zinc is a standard sun-blocking ingredient in mineral suncreams. It’s what makes them, and other formulas like Sudocreme, white).

Other false claims claiming there are toxins in suncream are not as explicit, but rather implied; they often try to sell “non-toxic” suncream to a public while amping up the suspicion of “chemicals”, such as those listed on the back of most suncream bottles.

However, as David Robert Grimes points out, even the chemical description of an apple can sound sinister when you don’t know what the terms mean. 

“Unless you’re talking about particles of light, everything in our tangible universe is chemical,” he said.

Long lists of exotic-sounding chemicals make up many anti-suncream posts, which warn that these chenmicals can be dangerous.

They often refer to oxybenzone, octinoxate, oxytocinate, octisalate, octocrylene, homosalate, parabens, PUFAs, avobenzone, or nanoparticles.

“If you can’t pronounce it, your liver’s already struggling,” one of these posts, viewed tens of thousands of times on X, reads.

“These ingredients don’t block UV rays. They absorb them. Convert them into heat. Your skin turns into a microwave. Congrats, you’re cooked.”

The last part of this claim is partly true, but is misleading in a way that purposely makes the process sound more sinister than it is.

Some sunscreen ingredients do absorb UV rays and convert them into tiny amounts of heat, but nowhere near the levels needed to cook or microwave a person’s skin.

The heat generated is negligible, and is far less damaging than the DNA mutations that UV radiation can cause on the skin when they are left unblocked.

Concerns about the chemicals in suncreams are also partly based in fact — some of the ingredients do have potentially negative health effects in high doses, which is why they are regulated.

In order to prevent this from happening, Europe places regulatory limits on them so they are far below any harmful thresholds when they are used in suncream.

“Sunscreens are cosmetic products and as such manufacturers must comply with strict European regulatory standards that include governance on ingredients, safety and labelling,” the Health Products Regulatory Authority (HPRA) told The Journal.

“The HPRA’s role as the competent authority is to ensure cosmetic products on the Irish market are safe for consumers and meet the requirements of the cosmetics regulation.

“When a cosmetic product comes to the Irish market, it undergoes a safety report, including product testing and likely exposure levels.

“Ingredients used in cosmetic products must be safe and must abide by the minimum standards to be met by all cosmetic products placed on the market.”

For sunscreams specifically, this means that only protective UV filters approved for that purpose may be used.

A list of UV filters allowed in cosmetic products, as well as what concentrations and what products they can be used in, is available on the European Commission website here.

“The HPRA continuously evaluate the inclusion of cosmetic ingredients at European level and in collaboration with other EU markets, to ensure the highest standards of consumer safety are maintained.

“Consumers should check for a European address on the label. If it is not there, it might indicate that the product has been imported from outside the EU and may not meet European requirements for safety assessment.”

Vitamin D and cancers

A near constant refrain on posts encouraging people to forego suncream is that sunlight is needed to make vitamin D.

“Sunlight increases your body’s production of Vitamin D which fights cancer. Sunscreen is full of chemicals that cause cancer,” a post by a self-described “Naturopath” said on X last July.

To date, the post has accumulated more than 2.4 million views, according to X’s analytics.

An identical post by an anti-Covid vaccine account using the exact same wording was also posted last August, and has accumulated a further 3.6 million views on the platform.

Although research has looked at whether Vitamin D can prevent cancers, the evidence has been “mixed” and there is no credible evidence that skipping sunscreen to boost Vitamin D is worth the well-established risk of UV-induced skin cancers.

“We don’t have rickets,” David Robert Grimes says. “That is your bog-standard test for nutritional deficiency.”

While it may seem intuitive that suncream, which blocks the sun’s harmful rays, would reduce the amount of Vitamin D produced in the skin, experiments have shown that volunteers that used suncream in the sun maintained vitamin D production, while reducing sunburns.

“Our bodies can still make vitamin D from sunlight even when using suncream,” the HSE told The Journal by email.

“The Department of Health recommends vitamin D supplements for everyone. The amount you need depends on your age, skin tone, your situation and the time of year.”

Cancer rates

“We were exposed to the sun for hundreds of thousands of years and were doing just fine until sunscreen was invented in 1938,” a post on X last June said. It was from an account that describes themself as “the most canceled scientist”.

“Since then, melanoma rates began to skyrocket in the 1950s, yet people blame the sun rather than the toxic chemicals in sunscreen.” The post has been viewed more than 1,800,000 times.

Melanoma is a particularly dangerous form of skin cancer.

Skin cancer diagnoses have increased over the last century, but there is no evidence that sunscreen is responsible. The rise is more accurately explained by much more obvious factors.

“Improved diagnostics, better reporting, and also that we live longer, and we have more time to accumulate that DNA damage that can lead to things like skin cancer,” David Robert Grimes said, listing other reasons why more cases of skin cancer are recorded now than in the past.

Melanomas have been recorded in history, including in the writings of Hippocrates, as well as archaeological evidence of melanomas on 2,400-year-old Peruvian mummies.

However, historical statistics on rates of skin cancers are scant. National Cancer Registry Ireland began collecting data on cancer cases in 1994.

“Over 5,000 cases of skin cancer were diagnosed in Ireland in 1994,” a spokesperson for the HSE told The Journal.

“It can take decades for skin cancer to develop after exposure to UV radiation. Many of those diagnosed with skin cancer in 1994 would have been exposed many years earlier when sunscreen was much less widely used or available.”

The connection between UV rays and skin damage is well established, as is suncream’s ability to stop these rays.

Grimes also listed living longer as a reason that more skin cancers are being detected nowadays.

“Cancer is primarily a disease of aging,” Grimes said. “Most cancers manifest post your 60s, right? There are exceptions, but almost all of them are associated with aging. The damage is done much earlier on, and then decades later, the cancer emerges. You might have got some exposure in your 30s that eventually leads to cancer in your 60s.

“So as we live longer, we get more cancers.”

Ingredients in suncreams are regularly revised in the EU based on the latest science and have strict limits to make sure their use is safe. Many claims about suncream being bad for you are based on incorrect data or faulty reasoning.

Not wearing suncream on sunny days can quickly lead to visible radiation burns and genetic damage, which increase the likelihood of cancer developing.

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