May is Melanoma and Skin Cancer Awareness Month, and as summer approaches, many of us will be embracing the sunny weather and spending more time outdoors.
One of the best ways to prevent these often deadly cancers is to use sunscreen. As summer approaches, we will be embracing the sunny weather and spending more time outdoors. But too much exposure to warm rays can put people at risk of skin cancer. According to the Canadian Skin Cancer Foundation, one in six Canadians will be diagnosed with skin cancer in their lifetimes. It is the top cancer killer of women ages 25-30 years old. And over 85,000 cases of skin cancer are diagnosed in Canada each year. The Canadian Cancer Society estimates that in 2024 11,300 Canadians will be diagnosed with melanoma.
But not all sunscreens are created equal. St. Paul’s Hospital dermatologist Dr. Angela Law breaks down the myths and misconceptions exist about sunscreens. She offers 10 facts about sunscreen to help you protect yourself and safely enjoy the sun.
1. Do I need to wear sunscreen daily, even in winter, or if I work inside?
Ideally, yes, as UVA (ultraviolet A radiation from the sun) passes through window glass and is more consistent throughout the day and throughout the year than UVB (which tans and burns you). UVA also contributes to wrinkles and other signs of aging, along with skin cancers. What’s more, even short exposures outside add up throughout the day, so daily sunscreen use is a good habit to develop.
However, some individuals may not tolerate certain ingredients in chemical and physical sunscreens and therefore other forms of sun protection may be used, like clothing and hats.
2. What sunscreen should I buy?
Look for a product that states SPF 30 or higher, broad spectrum, UVA and UVB coverage. SPF stands for sun protection factor and measures how long a sunscreen will protect you from UVB rays. (for instance, SPF 30 allows you to stay in the sun without burning 30 times longer than if you hadn’t applied any). Broad-spectrum products protect against both UVA and UVB rays. Higher SPF provides better protection by blocking a higher percentage of UV rays
3. What about Vitamin D – don’t I need to get it from the sun?
While sunlight is a significant source of vitamin D, there are other sources, including supplements and fortified foods. Usual sunscreen use does not interfere with vitamin D production but rigorous use of sunscreen and clothing may. The best strategy is to protect yourself from the sun and to take a daily vitamin D supplement of 1000 IU, with food. That way you get the best of both worlds, safely.
4. I have dark skin. Do I still need to use sunscreen? Yes, absolutely! Darker skin types have more natural protection in their skin due to higher levels of melanin, but can still be susceptible to sun damage, skin cancer and signs of aging (like pigmentation). Sun protection is essential for everyone, regardless of skin type.
5. What is the difference between chemical and physical sunscreens?
Chemical sunscreens, which typically contain ingredients such as oxybenzone, octinoxate, octisalate and avobenzone absorb UV radiation, which is then released from the skin as heat. Physical sunscreens, which contain zinc oxide and titanium dioxide, both reflect UV radiation and absorb it.
6. Which is better – physical or chemical sunscreens?
It depends. For people with sensitive skin or a history of allergy to sunscreens, physical sunscreens may be better tolerated. Physical sunscreens are also recommended for use in children. For most, it is a matter of personal preference. Physical sunscreens may appear more opaque and white on the skin, while chemical sunscreens are often more transparent and cosmetically appealing. Some physical sunscreens are tinted to better match skin tone.
7. Is any sunscreen truly waterproof?
Canadian labelling standards allow the terms Water Resistant 40 and 80, meaning that the product has been tested to retain its SPF after 40 or 80 minutes of water immersion. Sunscreens may not be labeled as waterproof and should be reapplied after swimming, sweating or toweling off.
8. How much sunscreen do I need to apply?
The teaspoon rule helps you apply enough sunscreen to match what is done in the lab when SPF is determined. Apply a half to one teaspoon to the face, one teaspoon to each arm, one to the chest, oneto the back, and two teaspoons to each leg. That’s almost 45 mL, or about a shot glass, of sunscreen per application! So it’s more than we think.
9. Apart from sunscreen, what else should I do to protect myself?
Wear a broad-brimmed hat and cover up with clothing wherever possible. Clothing labeled as UPF means UV Protection Factor, a similar concept to SPF, and is good for long sun exposure and beach wear. Protect your eyes with sunglasses or prescription glasses whenever you are outdoors. Plan activities early in the morning and later in the afternoon, avoiding mid-day sun between 11am to 2pm.
10. What is melanoma, how is it caused and why is it so deadly?
Melanoma is a form of skin cancer arising from cells called melanocytes. These cells are responsible for producing pigment in our skin called melanin. Melanoma is caused by multiple risk factors, including genetic predisposition, UV radiation, indoor tanning use, and multiple and irregularly shaped moles.
Melanoma can be deadly because of its ability to metastasize, or spread, even at an early stage. Some melanomas may be detected later on after they have metastasized and spread quickly, making treatment more challenging and reducing the likelihood of survival.
