Sunscreen Myths
Sunscreen plays a large role in protecting and maintaining the health and integrity of the skin. Around 80-90% of the changes we see in our skin can be attributed to UV (ultraviolet light) exposure from the sun. This makes sunscreen a must in anyone’s skincare regime to help prevent DNA damage, hyperpigmentation, inflammation and premature aging. For this month’s blog, I wanted to address some myths about sunscreen.
Myth #1: The SPF in my foundation is enough
In order to get the full protection provided by the sunscreen in your foundation you would need to apply ~1/4 teaspoon of the product for the face and neck. Depending on the foundation, this can be a rather thick layer of foundation that may not sit nicely on the skin. You would also have to reapply this quantity of foundation again if you plan on being outdoors for longer than two hours. So, you could end up with multiple layers of foundation sitting on your skin by the end of the day. If you are planning on spending a lot of time outdoors foregoing foundation and just using sunscreen on the skin will allow for easier reapplication and better protection. Or, you can apply your sunscreen in the morning, wait 30 minutes then apply your foundation and use a powder sunscreen throughout the day for reapplication. The powder sunscreen is less likely to disrupt your makeup.
Myth #2: I do not have to wear sunscreen when I’m indoors
Are you working or sitting by a window? Is there daylight coming into the building? Are there objects, such as trees or buildings blocking your view of the sun? This is actually very circumstantial. Glass can block a lot of the UVB rays (shorter wavelength of UV rays that cause sunburns) but not so much UVA rays (longer wavelengths of UV rays that cause premature aging) and if you are working near a window with direct sunlight (no objects blocking it) for extended periods of time it is best to be cautious and wear sunscreen for the UVA protection. If you are far away from the window and/or objects are blocking the sunlight, you would be experiencing diffused sunlight and you would not have to apply sunscreen as the exposure to UV rays is very minimal.
Almutawa, F., Vandal, R., Wang, S. Q., & Lim, H. W. (2013). Current status of photoprotection by window glass, automobile glass, window films, and sunglasses. Photodermatology, Photoimmunology & Photomedicine, 29(2), 65–72. https://doi.org/10.1111/phpp.12022
Myth #3: SPF 15 is enough protection
Let’s do a quick comparison. SPF 15 blocks 93% of UV rays while allowing 7% of them in contact with your skin. SPF 30 blocks 97% of UV rays and lets in 3% of UV rays. SPF 50 blocks 98% of UV rays and lets in 2%. Looking at these numbers SPF 15 lets in almost 2x the amount of UV rays compared to SPF 30 and 4x the amount compared to SPF 50. Keep in mind these numbers only apply when the correct amount of sunscreen is used. With all this in mind, it is generally better practice to apply sunscreen with an SPF30 or higher to reduce the amount of damaging UV rays from coming in contact with your skin, especially if your goal is to maintain healthy skin.
Myth #4: I need vitamin D – sunscreen will block vitamin D production
Recent studies have found that daily sunscreen use does not affect vitamin D production. In the real world setting we typically never apply enough sunscreen or we miss a bunch of areas that end up being exposed to sunlight, such as around the eyes, scalp, between the fingers, and toes. Therefore, there are enough areas of skin exposed to the sun that allows for the production of vitamin D. There is no need to worry that sunscreen will prevent vitamin D production. Only when you completely avoid the sun, do you start to experience vitamin D deficiency.
Passeron, T., Bouillon, R., Callender, V., Cestari, T., Diepgen, T. L., Green, A. C., van der Pols, J. C., Bernard, B. A., Ly, F., Bernerd, F., Marrot, L., Nielsen, M., Verschoore, M., Jablonski, N. G., & Young, A. R. (2019). Sunscreen photoprotection and vitamin D status. British Journal of Dermatology, 181(5), 916–931. https://doi.org/10.1111/bjd.17992
Myth #5: I tan so I do not need to worry about sunscreen or sun damage.
A tan is a sign of skin damage. Yes, it is correct that melanin production (skin pigment responsible for the tan) is a protective mechanism in response to UV exposure and helps to reduce further DNA damage. However, a tan is only the equivalent of an SPF 3, meaning 97% of UV rays are still being allowed into the skin destroying collagen and elastin leading to wrinkle formation, causing cellular death and increasing the risk of skin cancer.
D’Orazio, J., Jarrett, S., Amaro-Ortiz, A., & Scott, T. (2013). UV radiation and the skin. International Journal of Molecular Sciences, 14(6), 12222–12248. https://doi.org/10.3390/ijms140612222
Myth #6: Melanin-rich skin does not need sunscreen
A lot of the studies around sunscreens have been racially biased. A quick Google search on skin cancer will show predominantly white skin. When it comes to melanin-rich skin and skin cancer the development of melanomas is far less likely than among white people. However, it can occur and due to misconceptions and lack of public awareness, it can often go undetected until the later stages.2,3 In highly melanin-rich skin, skin cancer is common in areas where there is less sun exposure, such as the palms of the hands, soles of feet, under the nails and inside the mouth. With this type of melanoma (known as acral melanoma), sun exposure is less of a risk factor making sunscreen not very helpful in preventing this type of melanoma.1 However, melanin-rich skin can still develop UV-induced melanomas and squamous cell carcinomas, which sunscreen can help prevent.2,3 It is always best to speak with a doctor when noticing any changes to the skin, new moles, freckles, etc., regardless of the colour of your skin. Overall, sunscreen use can be beneficial for those more prone to developing UV-induced melanomas, and for those less likely, it can be used to prevent hyperpigmentation and sunburns.
1Adewole S. Adamson Assistant Professor of Internal Medicine (Division of Dermatology). (2022, September 13). Sunscreen wouldn’t have saved Bob Marley from melanoma, and it won’t help other dark-skinned people. The Conversation. https://theconversation.com/sunscreen-wouldnt-have-saved-bob-marley-from-melanoma-and-it-wont-help-other-dark-skinned-people-116979
2Foundation, S. C. (2021, January 21). Ask the expert: Is there a skin cancer crisis in people of color?. The Skin Cancer Foundation. https://www.skincancer.org/blog/ask-the-expert-is-there-a-skin-cancer-crisis-in-people-of-color/
3Team, C. C. (2020, October 12). What dark-skinned people need to know about skin cancer. Cleveland Clinic. https://health.clevelandclinic.org/what-dark-skinned-people-need-to-know-about-skin-cancer/
Myth #7: Our ancestors did not use sunscreen, so why should we? We are meant to live with the sun
The UV levels from the sun are a lot higher today than they were in the past. According to NASA, at one point the UV levels had been increasing over a 30-year period and levelled off in the mid-90s.2 With higher UV radiation comes a greater need for sun safety and protection. Our ancestors adapted to the sun with the production of melanin to provide some sun protection. However, they also used other means of protection. Anthropologists discovered Ancient Egyptians used a mixture of rice brain, jasmine and lupine to help absorb UV light, repair DNA and prevent tanning.1 The Ovahimba women of Northern Namibia have an ancestral tradition of applying otjize, a paste of butter, fat and red ochre. Researchers discovered that the red ochre provides these women with an SPF range of 3.5 to 10.4 Our ancestors may have not known about UV radiation and how the sun creates damage on a cellular level, but they did understand that the sun can cause burns and changes to pigmentation in the skin. So, they implemented early versions of modern sunscreen with what was available to them in their environment and also created clothing, parasols, tents and hats to provide that sun protection.3
1Drissi, M., Carr, E., & Housewright, C. (2021). Sunscreen: A brief walk through history. Baylor University Medical Center Proceedings, 35(1), 121–123. https://doi.org/10.1080/08998280.2021.1966602
2Dunbar, B. (n.d.). UV exposure has increased over the last 30 years, but stabilized since the mid-1990s. NASA. https://www.nasa.gov/topics/solarsystem/features/uv-exposure.html
3Jablonski, N. G. (2022, September 21). Sun exposure then and now: Why our ancestors’ skin was better without sunscreen. TheQuint. https://www.thequint.com/fit/skin-damage-sunscreen-sunlight-ancestors-sun-exposure#read-more#read-more
4Rifkin, R. F., Dayet, L., Queffelec, A., Summers, B., Lategan, M., & d’Errico, F. (n.d.). Evaluating the photoprotective effects of ochre on human skin by in vivo SPF assessment: Implications for human evolution, adaptation and dispersal. PLOS ONE. https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0136090