One in five British Columbians will get skin cancer in their lifetime, according to an expert with BC Cancer.
And despite campaigns encouraging people to slip into the shade, slap on a hat and slop on some sunscreen, skin cancer rates have been climbing for the past three decades.
There are more cases of skin cancer annually than all other types of cancer combined, said Dr. Sunil Kalia, a dermatological oncologist with BC Cancer, dermatologist with BC Children’s Hospital and professor in the University of British Columbia’s department of dermatology and skin care.
Why cases are rising isn’t exactly known, he said. It could be because people are getting more sun exposure, or patients and doctors are getting better at detecting the cancer.
But the past few years have also seen a rising trend in social media influencers claiming it’s the chemicals in sunscreen giving people cancer, rather than the sun.
Even Lululemon had its time in the sun, so to speak, spreading this misinformation.
Sunscreen has been widely used for 30 to 40 years, Kalia said. Studies have shown that it is safe to use.
Sunscreens fall into two main categories, chemical and mineral. Both absorb UV radiation and convert it into heat, thereby protecting skin from harmful rays.
Chemical sunscreens use carbon-based ingredients to protect your skin and can also be called organic sunscreens. The UV filtering ingredients in chemical sunscreens are classified as drugs in Canada, and packages will have a drug identification number on them.
In this context, “organic” means carbon-based, which is different from certified organic foods, which are grown without the use of certain pesticides and herbicides.
Mineral sunscreens can also be called physical or inorganic. They use the ingredients zinc oxide and titanium dioxide to protect your skin from the sun. Health Canada classifies these ingredients as natural products, and packages will have a natural product number on them.
Sunscreens with mineral and chemical ingredients will have both a natural product number and a drug identification number.
Both types are equally effective at preventing skin cancer, Kalia said. What’s most important is that you find a sunscreen that you like so you’ll wear it daily, he added.
Michelle Wong, a science communicator and cosmetic chemist who uses her chemistry PhD to help explain the science behind beauty products, offers a detailed breakdown of the differences between the two products on her blog.
In summary, both types are safe to use.
When people say chemical sunscreens are unsafe or “toxic,” they generally point to a 2001 study that found some risks associated with oxybenzone after scientists put high levels of the ingredient in drinking water for rats. But a followup study in 2016 found that for humans to get to similar risky exposure levels they’d have to apply full-body daily sunscreen for 227 years.
When in doubt, trust the experts, not the influencers, Kalia said. An easy way to do this is to look for sunscreen bottles that have the Canadian Dermatology Association’s stamp of approval.
“The benefits of wearing sunscreen and using sun protection strategies far outweigh the risks, which are basically all myths,” Kalia said.
Health Canada warns that sunscreens are meant to protect people’s skin when exposed to the sun, not to encourage people to lounge in the sun.
Who is at risk
Everyone, including people with darker skin tones and dark hair, should be wearing sunscreen if the UV index is higher than three, Kalia said.
The UV index, which ranges from zero to 11, is a Canadian invention that measures how strong the sun’s rays are. Most weather apps report current UV index alongside wind, humidity and temperature.
The average UV index in Vancouver from November to January is “low,” but February to October ranges from “moderate” to “very high,” which is when people should “protect skin as much as possible,” according to Health Canada.
Early spring can actually be one of the most dangerous times, because people forget that the cool weather can come with high UV index days, he said.
The people at highest risk of skin cancer are those with fair skin, light hair colour and pale eyes, for example blue or hazel, and who burn easily, Kalia said. But, he added, everyone is at some risk of skin cancer.
How to stay safe
The good news is that skin cancer is one of the most preventable types of cancer, Kalia said.
To protect yourself from the sun, Kalia said, stay indoors or in the shade between 11 a.m. and 3 p.m., which is when the sun’s rays will be strongest. If you’re outside, seek shade whenever possible and wear protective clothing such as a broad-brimmed hat and long-sleeved clothing. Avoid intentionally tanning.
Apply sunscreen to all exposed skin. Sunscreen should be higher than SPF 30 and heavily applied. That means using at least one teaspoon’s worth to cover your face, neck and ears, and an ounce to cover the rest of your body. Ideally, reapply every couple of hours or more if you’ve been sweating or swimming. But even applying once per day will offer some benefits.
Sunburns are most likely to lead to skin cancer, but it’s important to remember that all tanned skin is sun-damaged, meaning it’s at higher risk of developing skin cancer, Kalia said.
The Canadian Cancer Society recommends an annual exam to check for skin cancer for people with light-coloured skin, eyes and hair; people with many moles or freckles; people who had several blistering sunburns as a child; and people with a personal history of skin cancer.
This exam can be done at home following the ABCDE rule. People should check for:
A. asymmetrical moles,
B. with uneven borders,
C. with an uneven colour,
D. that are larger than six millimetres in diameter,
E. that have evolved so the colour, size, shape or feel of the mole has changed in the last several months.
If you have a sore that doesn’t heal normally in four to six weeks, have it looked at by a doctor, and keep an eye out for new or changing spots that look different from other spots on your body, Kalia said.
