Sunscreen Myths, Skin Cancer Risks and Safe Sun Exposure: What the Science Really Says

Kevin: Hey, Michelle, how are you doing today?

Michelle: I'm doing great, Kevin. Got your shorts on for summer shorts?

Kevin: I do. The sun is shining and it is glorious outside. And I am just ready to spend the whole day outside. But before I do, they always say, put on your sunscreen. Put on your sunscreen. And I understand that you have some information about that today. And you want to talk about sunscreen?

Michelle: I do. Okay. Something people frequently ask me about, like, is sunscreen safe? What if I have darker skin? Because I myself happen to be of South Asian descent. And you know, we have a saying that brown girls don't burn.

Kevin: Right. And I am from Northern England descent. So I am so lily white. I make Casper the ghost look tanned.

Michelle: You're like my husband, whom I call pasty white boy, and he calls me his little brown girl.

Kevin: So I have to slather on the sunscreen if I'm running out to the corner store. So yes, do tell me about sunscreen.

Michelle: Yeah. Well, my brown girls don't burn was grossly disproven when I was in Spain doing Camino de Santiago with my friend and her daughter and across the desert portion, Merceda, which was just very flat and it was very long and it was just in intense sunlight. I didn't know that's what was happening, but I got the worst burn that was actually blistery. And the anecdote is like, I called my husband after I realized this is what what had happened. And I said, I don't understand brown girls don't burn. And I just said, this is awful. How do you wait? People live like this.

Kevin: This is just this is awful. Welcome to our world.

Michelle: Then I acknowledged I have not been giving you the appropriate amount of sympathy.

Kevin: Yes, yes. It was the sun is my enemy.

Michelle: Right. Yeah. And so, Kevin, I never used to pack sunscreen like I've even previously gone to I did some hiking in the Galapagos near the equator. And I thought if I didn't burn near the equator, I'm not going to burn in Spain. But yeah, but but but you know that there is it depends on where you are and what you're doing and the intensity. And the the the bottom line for me was, you know, my my dad, I'm adopted, but my but my dad died of squamous cell carcinoma, which I now know I didn't know then is, you know, starts as a form of skin cancer, started with a little spot on his ear, a little spot in his lip. And he didn't he didn't look into it early enough and take care of it. And it turned into a huge tumor in his neck. And he went through chemo radiation and there were he had other comorbidities. But, you know, that really shook me awake for a bunch of reasons. But it really you know, now I look back on that. And plus the fact that I burned, even though I've got these, you know, beautiful pigments that are protective in my skin, you know, it's something that we all have to pay attention to. And it's not it's not something that we can be lackadaisical about.

Kevin: It's it can be very dangerous and and sun skin cancer can sort of creep up on you unexpectedly.

Michelle: Yeah. Yeah. And it's and it's on the rise. We we we need sun exposure. Sun's really healthy for us from a vitamin D perspective, as we know. But we have to use sun safety, right?

Kevin: Just like anything in life. Too much of a good thing can be bad for you.

Michelle: Yeah. Yeah. Yeah. I'm going to try to break this down and keep it and keep it kind of short. But, you know, just just to preface, you know, why I looked into this, the kind of common questions I get because the type of nutrition that I studied originally in school was registered holistic nutrition. And from a holistic perspective, people are always really concerned about what exposure to toxic chemicals and disruptive hormones or things are you getting? Is the sunscreen worse than the sun kind of thing? I think that that's a concern for some people.

Kevin: The lesser of two evils.

Michelle: But when I look at what the actual peer reviewed science says and when I say peer reviewed science, I mean, this isn't just like North American perspective, Canada, Australia, Europe, Asia and the US, you know, I'm going to I'm going to separate the facts from fiction here.

Kevin: Please.

Michelle: So the most important question, does sunscreen work? Yes, it works.

Kevin: You heard it here first, folks. Sunscreen works.

Michelle: It will reduce sunburn. It reduces DNA damage to skin cells. It reduces precancerous skin lesions. It will reduce the squamous cell carcinoma risk, the type that that my father developed, and it will likely reduce melanoma risk when it's used consistently over time. Melanoma is a is a bit of a different animal, but it is it can be positively impacted by the use of sunscreen on a consistently over time. OK, now the thing is, here's the nuance. Sunscreen only works well under ideal conditions when it's studied. But in real life, what's actually true is that people usually don't use enough. They don't get sufficient coverage and they don't reapply it often enough because they rely on the label itself. You know, it'll say, you know, all day or sport or like it'll have all these water resistant nice claims. And then that kind of gives people a false sense of security. So the real world effectiveness is often actually lower than the SPF number suggests. Right. So it doesn't mean that the sunscreen doesn't work. It just means that human behavior limits its ability to perform as designed. Right. Yeah. So here are some of the global perspectives. So a lot about what we read or hear about here in Canada is based on U.S. research and U.S. media. But the science on sunscreen is global. So, for example, in Australia, skin cancer rates are among the absolute highest in the world. And they've done a lot of research on this. And decades of population studies show that sunscreen does reduce skin cancer risk. In Europe, sunscreen formulation research is much more advanced than some of the North American research, particularly when it comes to UVA protection. And Canada uses a very highly regulated system. And in Canada, our system emphasizes sunscreen as part of a broader sun safety strategy. I'll get to that in a bit. And then there's Asia. There's extensive research on pigmentation because of more brown skin people, UVA exposure and visible light effects on skin. So across all of these regions, the consistent conclusion is that UV radiation is carcinogenic and sunscreen is an important strategy to reduce UV damage. And there is no major scientific body anywhere in the world that recommends against sunscreen use. So that's the first kind of level set for pretty unanimous. Yeah, right. Now, what about this toxicity exposure? Right. And it's a valid concern, but often that concern gets exaggerated or misunderstood. So some studies show that certain sunscreen ingredients can be detected in the bloodstream after application. That's absolutely true. But there is a scientific distinction, Kevin, because detectable does not mean harmful. And this this kind of hearkens back to some of the things that Dr. Deborah Kyle said when we had her on the episode about PFAS. Just because you can have a finding doesn't mean that it's actually going to cause a health event, right? So to date, there are this is to be clear, no high quality human evidence showing that sunscreen use causes hormonal disruption, cancer or systemic toxicity in real world exposure levels. That real world exposure level is very important, right?

Kevin: Yeah.

Michelle: So the evidence supports two things at once. Absorption can occur, but harm has not been demonstrated. Right, right. So those are very, very different conclusions.

Kevin: Yeah, that goes back to our episode. I forget exactly what we were talking about, but we were talking about the chemicals on strawberries. And I remember, you know, there was some fact that to actually do any damage, you would have had to have eaten like 20 bushels of strawberries to get enough of the chemical exposure to actually do any damage. So same right thing here.

Michelle: Right, right. And what the global studies have concluded is that the risk of the damage and the health risk from the sun exposure far outweighs any risk from the absorption of the constituents of the sunscreen. Now, that said. I do have this holistic side to the way that I like to look at things in conjunction with the broader evidence. And I still think there's this case to be made for, you know, what are the worst offenders that we can avoid if we're reading labels? Because, you know, just because everybody could be hit by a truck doesn't mean that you want to step in front of it, right?

Kevin: So that's an interesting analogy. OK, Michelle, we'll go with that.

Michelle: OK, well, I mean, like it's always I'm always about the real world, but I'm also about the best quality within your means and the best quality. Like if all you have to do is read a label and you can make a better choice of a better sunscreen product, why wouldn't you? Exactly. So some of these names are scientific and a little bit difficult, but I'll do my best. So oxybenzone or benzophenone 3, that is something when you turn over the label that you might see as an ingredient in your sunscreen, it happens to be the most scrutinized ingredient of all of the potential ingredients in sunscreens. And the concern is it is readily absorbed systemically with detectable levels in blood plasma, urine, amniotic fluid and breast milk. Whenever something is detectable in breast milk, I think that causes people to raise their eyebrows quite a bit higher. And a comprehensive review found that peak plasma concentrations after a single whole body sunscreen application may overlap with concentrations producing endocrine disrupting, that's hormone system disrupting effects in vitro. So it can cause different problems, estrogenic problems, cycle issues, other endometrial issues, et cetera. Now, those studies have been on rodents. There is limited human data, but limited human data does suggest that it can have associations with menstrual cycle alterations and increased uterine fibroids, et cetera. So anyway, long and short, the European Commission Scientific Committee on Consumer Safety recommends reducing the concentrations of that particular chemical.

Kevin: OK.

Michelle: And as you know, not coincidentally, you don't actually really see that ingredient that much anymore, but it's worth having a look. So it was oxybenzone was that one. Then there's another one, homosalate, and it was flagged by the SCCS, which is the Scientific Community on Consumer Safety. So that's an independent advisory board to the European Commission that evaluates health and safety risks in non-food consumer products. And they flagged it for potential endocrine disrupting properties with a recommended maximum concentration of 0.5 percent, which that's important because in the U.S., the U.S., their limit on sunscreens of that particular chemical is 15 percent.

Kevin: Oh, wow. Right.

Michelle: So, yeah, that's so that one's that one's worth making sure you don't see in your ingredient list homosalate.

Kevin: OK.

Michelle: And then octinoxate demonstrates systemic absorption and has been implicated in thyroid hormone disruption. Again, this is in animal models, not in human models. However, this is the thing for me. It's been found to be toxic to coral reefs.

Kevin: Hmm. OK.

Michelle: So it's banned along with oxybenzone in several jurisdictions because of the environmental risk.

Kevin: So if you see the reef safe sunscreens, yeah, that's a good point to have that. Right. And I'm just going to add a small PSA for the reef safe sunscreens because I'm a scuba diver. Yes. And so I strongly believe in this. If you are anywhere in an ocean near a reef or near marine life or anything, please use a reef safe sunscreen. However, also be aware that I don't know what these ingredients do, but generally being reef safe makes them slightly less water and sweat resistance. So you will have to reapply it more frequently. And I learned that the hard way on a trip when I got a bad burn. It's like I use sunscreen the way I normally do, but it is less I think it's like a sticking agent or I don't know what it is. But the reef safe ones generally don't last as long against sweat and water.

Michelle: That's the reason for these other the reason why these other ingredients were included, because they probably have more staying power. But there is a trade off between that staying power.

Kevin: Exactly. And then these other risks, the marine life and corals.

Michelle: Yeah. And then there was one other. So I had the four top to avoid octocrylene again, also detected in breast milk.

Kevin: It sounds like a it sounds like a Marvel villain. Octocrylene, you won't get away with this.

Michelle: Marble villain. And again, you know, this one does you know, it's potentially indicated, you know, for contact dermatitis. Like so to be like the for some folks to have an allergic reaction to it. But again, it's environmental concerns for toxicity to marine animals. So, you know, I'm saying, you know, if we're going to go in the oceans, then let's let's keep these things.

Kevin: Let's not kill all the fish and corals.

Michelle: Right. Right.

Kevin: So, Michelle, I'm wondering. So so this is super interesting. I'm just wondering if you have any information about mineral based sunscreen, because that's different from the chemical. And I'm curious because I actually use mineral based sunscreen. So I'm I'm a little scared, but also very interested in what you have to say about those.

Michelle: Yeah, absolutely. Mineral sunscreens are a really great option, especially for people that are that are concerned about that absorption issue. That's one way to to almost completely avoid it. And so a mineral sunscreen, just so that the noobs are aware, would mean like a zinc oxide or a titanium dioxide. The difference is that these sunscreens tend to sit on the skin's surface. So you don't get the absorption. You'll see it on your skin. It'll be like a little bit pasty, a little bit white.

Kevin: But on someone like me, you can't even tell because I'm normally pasty and white.

Michelle: Well, you can tell on me. And you know what? I most often use that kind of sunscreen, too, unless I forgot to bring it. And then I'm using, you know, whatever somebody had that I could borrow. It provides strong UV protection when it's properly formulated and properly applied. The trouble is that a lot of people don't like that cosmetic effect of having that little bit pasty, you know, where you can feel it. It feels thick a little bit.

Kevin: Yeah, it feels a bit thick. But I like it because generally it's really easy to find 60 SPF in mineral. So that's generally why I use it. Whereas the 60 FPS in chemical sunscreens tend to be a little bit harder to find. So that's why I like the mineral ones.

Michelle: To increase that SPF, they have to increase the chemical content. There is a trade off there. So there's going to be more chemicals in the higher SPF. I think the guideline is to use SPF 30 and higher. And if you're like me and you're lucky enough to have those darker pigments in your skin, you naturally, depending upon how dark your skin is, you generally have somewhere between eight and 15 SPF naturally. I think I have negative five SPF naturally. Yeah, you and you and my spouse both. Yeah. They say that SPF measures UV protection and not chemical toxicity. The reason I believe that there is a higher trade off is because I did attend a conference one time where an immunologist made that statement to the group in her lecture. Was that there was a higher level of chemical ingredients in order to achieve that higher UVB protection. Right. Right. So, you know, but at the end of the day, what really matters is how much sunscreen you apply, how often you reapply it and how much of your skin you actually covered. That's actually more important than the SPF number of the sunscreen that you're using, because most times when these aren't providing the protection that people are looking for, it's because of user error.

Kevin: Yeah. If you if you apply a 30 properly, that could be better than a 60 applied improperly. Right. And there's also I just want to add also, if people are concerned with with the chemicals and SPF and using too much. I mean, there's also this brand new invention that I've heard of. You might not have heard of it before. They're called clothes and hats. And but I think but but in all seriousness, I think also with more awareness about the sun, I think socially it's it's more acceptable now to wear, you know, lighter fabrics that block the sun, that physically block the sun. So you can wear long sleeves. You can even wear I see people wearing gloves. You know, you can wear big fluffy sun hats like, you know, longer pants that still keep you cool, but that protect you so you don't have to apply sunscreen to as many parts of your body.

Michelle: You're absolutely right. It's way different than the than the 70s when I was a little kid in the 80s, when I was a teenager, when it was when it was like culture to lay out and slather yourself in baby oil.

Kevin: Wear as little clothing as possible, have as much of your skin exposed and yet put on a Hawaiian tropic that actually acts to like grill you even more. But, you know, I mean, in my travels and in Vietnam and Japan and elsewhere, and I'm sure you saw it in China, like people physically dress. So absolutely covered head to foot because the sun can be so strong, especially in the summer months, especially in subtropical climates.

Michelle: I find I find that they already they already know this. Right.

Kevin: Exactly. It's second nature to them.

Michelle: We have a bit of complacency that in Canada, I think, because we don't get the same level of sun exposure, we think that we're less at risk. Right. Right. We don't feel that same intensity. Let me tell you what Health Canada's guidelines are, and then maybe we'll do a part two to this episode because I want to touch on some of the nutritional implications of protecting from the skin. Sure. So Health Canada's guidelines for UV exposure risk is that it's the highest between 11 a.m. and 3 p.m. here. Right. And it's the most intense between April to September. That's probably not a surprise. Those are the times when the UV exposure is at a level of three or higher. And also not to get complacent when it's cloudy outside or snow, dry sand, even concrete. Concrete can actually reflect the sun's rays like a mirror and increase the amount of UV exposure. Mountains, more UV reaches higher places because the air is thinner and clearer.

Kevin: From skiing, you have to be aware of that. Even in the middle of winter, you have to wear on your nose and your cheeks. You have to because I've gotten some bad burns from skiing in the middle of winter. But I'm up high. And so the sun's closer to you.

Michelle: Exactly. So just like you said, Kevin, you know, wear some clothing that covers most of your skin. Wear a wide brim hat and long sleeves. And you can even buy those. My friend Karen, when we walked Camino, actually had sleeve guards or something. I don't know what they were called that covered her arms so that she wasn't exposed.

Kevin: I have light gloves that I use when paddling a canoe or a kayak. Because when you're in the middle of the water, also the water reflects horribly. And so for the backs of my hands, I have these silly nerd gloves. I love them.

Michelle: Oh, I bet you make them fashionable.

Kevin: I do. I try my darndest. You rock those gloves. I rock those nerd gloves.

Michelle: So it also says to make sure that you're putting on plenty of sunscreen and that you're getting sufficient coverage and reapplying every two hours. Do not try to tan on purpose. If you have if you do get a sunburn, apply aloe or flaxseed gel to soothe and cool the skin. And Health Canada does not, by the way, recommend tanning beds, especially for people under 18. They don't consider those safe. Right. It's also too worth noting before we wrap this up to think about your eyes, your eye health as well. Wearing sunglasses or eyeglasses with UV protective lenses because you can actually do damage to your eyes.

Kevin: My optometrist always reminds me of that.

Michelle: Oh, really? That's cool.

Kevin: Yeah. My optometrist always says your eyes look good and, you know, asks me explicitly and you wear proper sunglasses with UV protection to keep them that way.

Michelle: Cool. Well, that's that. And maybe we'll come back, come back for a part two and we'll talk about the what role nutrition plays.

Kevin: Exactly. That would be interesting. Amazing. Well, thank you, Michelle. I'm ready to go outside and enjoy the great outdoors in summer.

Michelle: Yeah.

Kevin: Awesome. OK, so for our joke that has nothing at all to do with, I'm actually realizing it's more of a Halloween themed joke than summer, but whatever. We go with it here.

Michelle: That's random.

Kevin: Because we're sometimes, I'm sometimes very, very random.

Michelle: You never know. Somebody might not listen to this episode until October.

Kevin: So exactly. Yeah, exactly. So why don't skeletons ever go to the movies?

Michelle: Why don't skeletons go to the movies, Kevin?

Kevin: Because they have nobody to go with. Ah, but I'm bummed. And on that note, I hope everyone enjoys their summer and I hope you enjoyed this little summer short. And we will be back in two weeks with another one. And in the meantime, eat your greens. And be real, everyone. Practice safe sun. And apply your sunscreen and practice safe sun. This has been Nutrition for Noobs. We hope you're a bit more enlightened about how your fantastic and complicated body works with the food you put into it. If you have a question or a topic you'd like Michelle to discuss, drop us a line at hello@nutritionfornoobs.com. If you haven't already, you can subscribe to the podcast on whatever your favorite platform might be. Also, please consider leaving a review or telling your friends. That's the best way to spread the word. We'll see you next time. With another interesting topic. The views and opinions expressed on Nutrition for Noobs are those of the hosts. It is not intended to be a substitute for medical, nutritional or health advice. Listeners should seek a personal consultation with a qualified practitioner if they have any concerns or before commencing any actions mentioned in the podcast.