Derm-it Trotter! Don't Swear About Skincare.
Feeling frustrated or overwhelmed with everything skin? Does the skinformation overload make you want to swear about skincare? Join Dr. Shannon C. Trotter, board certified dermatologist, as she talks with fellow dermatologists and colleagues in skincare to help separate fact from fiction and simplify the world of skin. After listening, you won’t swear about skincare anymore!
Derm-it Trotter! Don't Swear About Skincare.
Rethinking Sun Protection, Part 1: Why Sunlight Might be Good for You
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Dermatologists have long warned about the dangers of sun exposure, but what if our relationship with the sun doesn't have to be one of constant fear? In this eye-opening conversation, Dr. Shannon Trotter welcomes Dr. Katie Varman, a board-certified dermatologist specializing in photoimmunology and functional medicine, to explore the surprising health benefits of moderate sun exposure.
Dr. Varman challenges conventional thinking by presenting compelling evidence that sunlight offers significant health benefits beyond vitamin D production. She reveals how UV exposure impacts cardiovascular health by triggering nitric oxide release from the skin, resulting in improved circulation and reduced heart disease risk. The discussion ventures into fascinating territory as Dr. Varman explains how sunlight exposure actively shapes both our skin and gut microbiomes, decreasing harmful bacteria while promoting beneficial ones that may even help protect against skin cancer.
Perhaps most revolutionary is the explanation of how moderate UV exposure creates immune tolerance through the production of regulatory T-cells and B-cells—a mechanism that explains why phototherapy effectively treats inflammatory conditions like psoriasis and eczema. This balanced perspective gives listeners a new framework for understanding sun exposure: not as an enemy to be avoided at all costs, but as a natural element requiring a thoughtful, personalized approach.
By the end of our conversation, Dr. Varman provides practical guidelines for optimal sun exposure (5-30 minutes of midday sun, three times weekly) while hinting at additional protective strategies through nutrition and supplements. This episode represents a significant shift in how we think about sun health, empowering listeners to make informed decisions that balance protection with the undeniable benefits of sunshine.
Stay tuned for our next episode with Dr. Varman, where we'll discuss how diet and nutraceuticals can further support healthy sun exposure while minimizing risks.
Introduction to Skin-Sun Relationship
Speaker 1Welcome to Dermot Trotter Don't Swear About Skin Care where host Dr Shannon C Trotter, a board-certified dermatologist, sits down with fellow dermatologists and skin care experts to separate fact from fiction and simplify skin care. Let's get started.
Speaker 2Welcome to the Dermatrotter Don't Swear About Skin Care podcast. On today's show we have Dr Varman here. She's a board-certified dermatologist and works in private practice at Shine Functional Dermatology in Northern California. Dr Varman specializes in treating chronic skin conditions like psoriasis and eczema, with a blend of conventional and functional medicine practices. She also has a passion for photoimmunology or basically, how does light and the immune system sort of intertwine and affect each other, which we're going to talk more about today and she's also the owner of Shine Nutraceuticals as well. Welcome to the podcast, dr Varmund.
Speaker 3Thank you so much for having me.
Speaker 2So, dr Varmund, I know, or Katie, if you don't mind if I call you here on the podcast today you know, as colleagues you know, I think in dermatology you know we sort of get blamed for making the sun sort of this evil entity. So my hope was to have you come on today talk more about, you know, the benefits, that there are benefits of sun exposure. As dermatologists, that we're not, you know, completely against that in the sun and kind of you know how you explain that to a patient or how you want to walk us through that a little bit so we have a better understanding of our relationship, you know, with the sun and that it doesn't have to be one that's full of animosity and hatred.
Beyond Protection: Sun's Hidden Benefits
Speaker 3Exactly, and and I think you know, coming out of dermatology residency all of our training is geared towards sun protection, because we know that there's a lot of damaging effects that the sun has on the skin, whether you're just talking about sunspots and freckling or things like skin cancer. We know that there's a very direct relationship between too much sun exposure and skin damage and cancer. But what we don't talk about so much in residency and training and everything are the benefits of sunlight, and that's something that I developed a passion for just kind of very organically throughout. Um, you know, my kind of my first five years or so in practice, um is is really learning that there are benefits to sunlight exposure.
Speaker 3And then how do we as dermatologists kind of bridge that gap for people so we can really educate about how to get enough sunlight exposure to get, you know, reap all the benefits for your body as a whole, but then also be mindful of not overdo it and put yourself at unnecessary risk of skin cancer and photo aging and all of those things also. And so what I've really been working on is how do we navigate that space and how do you educate people so that they can get the sunshine which isn't? You know, it's not baby oil and burning and all of this. It's a moderate amount. But how do you get that so that you can reap the benefits and then support your body using things like diet, you know, nutrition and sometimes nutraceutical, to tolerate light well enough and not put yourself at a necessary risk. Tolerate light well enough and not put yourself at a necessary risk. And so that's what I love talking about, and I think today we'll talk a lot about the benefits, just to set that stage.
Speaker 2Yeah, and I like how you talk about you know the sun doesn't have to be. You know our enemy, if you will, and I think that's something important for dermatologists to really think twice about, because I think it is a little taboo in our own specialty and sometimes we do get on our high horse a little bit about some protection. Obviously you know going after someone's risk of skin cancer and trying to really make them diligent about protection, but why don't you touch a little bit on? You know just, I think, the health benefits for a son and talking about that, you know kind of how that plays a role, maybe, whether it's with the immune system or maybe benefits for the heart as well. You know things like that.
Cardiovascular Benefits of Sunlight
Speaker 3Yes, and and in dermatology, I focus a lot on the benefits of sunlight when it comes to autoimmune and inflammatory conditions. Right, because we know we use UVB therapy, phototherapy in dermatology to treat inflammatory conditions like psoriasis and eczema. So there's certainly benefits when it comes to those types of skin conditions, but it does expand much more broadly. So, to kind of touch on the main topic. So, like you said, cardiovascular disease, there is no paucity of literature when it comes to benefits for cardiovascular disease. Um, dr Richard Weller, out of the UK, way back like in early as, like you know, 2010 or so, in this um time period, he he was already talking a lot about the benefits of sunlight when it comes to cardiovascular disease and he presented a Ted talk with this beautiful chart of, like, uh, the UK and you can see this very clear risk gradient when it comes to UV exposure and cardiovascular disease. And what he talks a lot about is is, you know, people attribute it to vitamin D deficiency, everything vitamin D, vitamin D, vitamin D. Oh yeah, sun is important because of the vitamin D, but it turns out that sunlight gives you has many, many, many more effects on the human body than just vitamin D, and so he really outlines the benefit for cardiovascular disease really nicely and there's tons of literature to support that as well and independent of vitamin D. What sun does is it releases stores of nitric oxide from from the skin and then you get this beautiful base of dilation. You get like reduced platelet aggregation and all of these downstream effects from sunlight on the skin that are both dependent and independent of vitamin D, um, which really pretty dramatically decreases cardiovascular risk. Um so, so, um, cardiovascular is a is its own topic, but definitely sun exposure is very important.
Speaker 3And then there's other inflammatory and autoimmune conditions. So outside of the skin we see that same latitude relationship right, where if you live at the northern latitudes, you're at a much higher risk of developing autoimmune conditions like multiple sclerosis, type 1 diabetes, even an inflammatory bowel disease, than if you live at the lower latitudes. And again, it was always vitamin D, vitamin D, vitamin D. But we've had huge, huge, huge studies with tens of thousands of patients that have been published independently in the last 5, 10 years that really don't show a huge benefit from vitamin D supplementation. And so there's this kind of like disconnect. It's like, well, all of these diseases are associated with deficiency in vitamin D and yet, when we supplement, we're not seeing a reduction in all cause mortality. We're not seeing reduction in cardiovascular disease to the degree that we should.
Speaker 3So what is it? And it's like? Well, it's obvious, right, if there's benefits to sunlight that extend beyond vitamin d, so um, sunlight autoimmune and inflammatory mood benefit. There's microbiome benefits, which I'd love to talk more about too, both in the gut and on the skin. Um and so there almost isn't a part of human physiology that isn't touched by by sunlight exposure. It's really not just the skin.
Speaker 2Well, let's dive into that microbiome. We've talked about this before on the podcast, you know. We tell our patients and talk about hey, there's lots of bacteria, viruses, fungi, yeast I mean living on the skin, microorganisms too, as we all know, kind of hanging out in the gut and really determine our immune health. What does light exposure or sunlight do for our microbiome?
Speaker 3Micro and microbiome is definitely one of my most favorite topics, but from a from a skin perspective, what we know a lot from UVB studies, but also just in general with sunlight and mouse models and everything is that when you shine ultraviolet light on the skin, you have it changes the flora of the skin, cause we all have bacteria. Most people are familiar with the microbiome of the gut, but we all have a microbiome on our skin as well and, like you said, that microbiome is responsible for the immune system in the skin. It plays it like a marionette, right, and it's also responsible for the integrity of the skin. So the strength of the skin conditions like eczema.
Sun's Impact on Skin and Gut Microbiome
Speaker 3We all know that staph bacteria and eczema go hand in hand. Where it's actually degrading, you know, the barrier function of the skin, and so the composition of the microbiome on the skin makes a very big difference in overall skin health. And what UV light does is it decreases levels of staph aureus, right, the staph aureus is the dangerous not necessarily dangerous, it's normal flora, but it can become problematic on the skin when it's overgrown and strep bacteria as well. It also decreases types of yeast on the skin, something called pterosporum, which can cause problems for certain people when it overgrows and then it also increases beneficial bacteria. So there's a type of bacteria called Staph epidermidis which actually has benefits on the skin, and there's animal models that show, called staph epidermidis, which actually has benefits on the skin, and there's animal models that show that it reduces the risk of skin cancer after.
Speaker 3UV exposure when you have a good amount of staph epidermidis and it increases what are called antimicrobial peptides, which gives you good defense against other bacteria. So on the skin we really have some pretty robust evidence that the microbiome can be balanced by UV. But at the same time it's a balance right. If you overdo UV it's a Goldilocks phenomenon You're creating inflammation and you're creating problems. But the same thing, if you underdo it, you can allow overgrowth of some of these pathogenic kind of more obnoxious organisms. So on the skin there's that nice sweet spot.
Speaker 3But then what we also know is in the gut, and a lot of people don't realize that sunlight on your skin influences your whole body and the gut microbiome actually is influenced as well. It increases the diversity of the gut microbiome, which we know is associated with better health, and that is independent of vitamin D. So again, vitamin D is very important, but it's not the whole picture. And what's fun is, in mice you can actually knock out vitamin D and so you can prove these things right. You know for a fact that it's not the vitamin D because you like knock out the receptors in these mice and they still have the benefit and the diversity. So so from a microbiome perspective, sunlight absolutely can help balance it when you have the appropriate amounts.
Speaker 2Nate, you're probably going to blow a lot of people away with what you just said, because I think vitamin D has been a hang up for a lot of us. You know, even you know, from dermatology to oncology, I mean looking at those levels, really stressing the value and importance which you know it definitely is there, but, like you said, it's not the whole story or the whole picture. So I think getting people to understand that and appreciate that very important what you highlighted. And then also, I think minds might be blown by the mere fact you said you can get ultraviolet light to maybe help prevent skin cancer. You know, I think people in their minds what, wow, I mean I, you know you said that along with everything else.
Speaker 2But I really want to, you know, focus on that just as a point, because I think that would be shocking to a lot of people out there, and even our dermatologist colleagues that listen, you know, to really understand that value or role, because we kind of you know, the pendulum swung kind of far the other direction of, like gosh, you know, almost live like a hermit, live like a hermit. The focus, though, or the, I would say kind of the you know what I hear you saying, and I think, emphasizing this, like so many things in life and I'm a big proponent of this it's just simply, you know, moderation and balance. You know it's amazing how balance comes back into our lives in so many forms and I think it's just interesting the way you present this and the information that you know sunlight, ultraviolet light, you know, is in the same way that we should think about it, which makes sense. I mean, we're all here on this planet, you know, for a reason. We have the sun to do so many great things. But, like anything else, too much of a great thing may be bad. Too little is too bad and again it's, like you said, that sweet spot right in the middle.
Building Immune Tolerance through Sunlight
Speaker 2So I really think that's a great take home message that you're kind of highlighting there for our listeners as well. So how do you talk about sort of like some of the other you know? Are there other comments on the mechanisms, like how it helps, like with the immune system and its activity? Just touching on ultraviolet light, is it something that can suppress the immune system to, or you mentioned it for inflammatory disease, or it might be helpful if somebody has eczema or psoriasis? You know, just kind of that increased tolerance that you know it's kind of a concept people talk about. What are your thoughts on those types of things?
Speaker 3Yes, and that was really what kind of brought me to to learn a lot more in this kind of area of photoimmunology and how the immune system influences the I'm sorry how sunlight influences the immune system. And the whole idea of tolerance is essential to everything. And so what's a really really, really important point to make and something that, unless you really think about it, it's not entirely obvious. But when you are exposed to, say, a grass or a dander or something you know, a potential allergen, when you do not have a reaction to that dust, um, it doesn't. It's not the absence of a reaction that's going on in your body, it is a very active phenomenon that's happening where your body is seeing that allergen and it's communicating and talking and it's deciding I'm not going to react because you've developed tolerance to it. So the absence of a reaction is actually a very, very active phenomenon. Your body is making a decision with absolutely everything it is coming into contact with and it's that balance, right, it's the balance of reactivity or tolerance, and that is such. It's such an important point to make when it comes to things like eczema, because when you're looking at um, when you're looking at eczema, they're tipped towards reactivity, right, like everything in an eczema, is in specifically atopic dermatitis um picture where you're there's, you know, all sorts of developing IgE very typical allergic there's, you know, also developing IgE very typical allergic reactions to, you know, to airborne allergens, and you're getting asthma and food allergies. And it's just this very reactive picture. And what the whole goal is? To help that person create tolerance to their own bodies, because we know they're autoantigens and eczema as well, where the body is developing antibodies against your own body at that point. And so we want to help the body create tolerance to their own body, but then also to the entire world around them. And when your body is inflamed and primed, we know that you're at much, much, much higher likelihood of developing even more allergies over time. And so that's why when you have to be very careful what you put on eczema skin, because if you're putting soy and wheat and food products and all these kind of things on eczema skin, you're much more likely to develop a new allergy or fragrance or whatever. So this idea of tolerance is is really really critical um and uh, and there are ways that we can skew whether you develop tolerance or whether you develop allergy.
Speaker 3Um and one of the biggest things to to the biggest things sunshine and the microbiome, um, um, in the gut, um, and we'll talk a little bit more about sunshine, cause, that's what we're talking about today and that's my fun.
Speaker 3But um, my favorite thing, but um, but in the gut.
Speaker 3We know that the microbiome is largely responsible for whether those little T cells, so those immune cells that are floating around, whether they go down the pathway of being reactive or whether they go down the pathway of being tolerant and um and not reacting against dust standards and all those, all those things, um, and the gut microbiome plays a role because the all those little bacteria sitting in there and the good guys, when you feed them fibers and polyphenols and all the lovely stuff they essentially excrete, all these things that tell your T cells to become regulatory cells, become tolerant of the world and the environment and stuff that you see in your gut Versus, without those we call them short chain fatty acids and other byproducts, you become more reactive.
Speaker 3And so the gut microbiome plays a very, very big role, which is why Western diet and everything like that is so problematic. But the other half of it is the sun exposure and sorry, that's a long-winded answer to get there. But sunlight and it was mind-blowing to me when I first learned about it is specifically UV light creates tolerance both in the skin and internally at the level of, like the spleen, the lymph node, the bone marrow.
Speaker 3Um, and stop me if I'm rambling, but, um, but but, studies that go back to like the early nineties and eighties where this Dr Kripke and her team they were the ones that first really identified the immunosuppressive effects of sunlight specifically in the skin. So if you blast a little mouse, you know, with radiation, with UV radiation, they'll get skin cancers, they'll get tumors. But those little tumors are actually very antigenic, meaning your immune system can see them really really easily. So if you put that little tumor on another mouse, it gets rid of it, no problem, just clears it. And so she's like okay, well, maybe there's something immunosuppressive about, you know, this light.
Speaker 3And so then they did studies where they put strong sensitizers, so things that should cause an allergy, onto the ears of these little mice. And if you put an allergen at the same time as UV exposure, especially UVB, the mouse will actually develop a tolerance to that allergen or less of a reaction. And so they identified that UV causes immunosuppression, enough that you develop tolerance. But it's not just that you're blocking a reaction, you're creating regulatory T cells and so that tolerance is sustainable. Meaning next time if you expose to the allergen, even without the light, they won't react because you have those T cells and it's transferable. So you can take that and shove it into another mouse and then they also won't react to that allergen. And that's kind of how we found that sunlight makes regulatory T cells and then we found later that it also makes regulatory B cells deeper in the body and so it is immunosuppressive in ways which can create skin cancer not so great. But it's also immunosuppressive in a much more delicate way where it calms down what might be an otherwise overreactive immune system.
Speaker 2Very cool and I think that's where people may have heard the connection like how in the world, as a dermatologist, could you recommend light therapy or phototherapy for my eczema or psoriasis, when you know you're always telling me to protect my skin because you don't want me to get skin cancer?
Practical Sun Exposure Guidelines
Speaker 2And I think that was a great summary to help you know patients understand this is the why you know this is where there is potentially a role and where it can really affect the immune system and those skin conditions where the immune system is a little too active and again out of balance system and those skin conditions where the immune system's a little too active and again out of balance. And we're trying to bring that balance back to the skin with light therapy or phototherapy. So, in our last few minutes, what type of personal recommendations do you have for you know just the kind of sun exposure that you think is appropriate, based on risk factors. You know benefits but at the same time, minimizing risk for patients, because I think that's the thing again, people are trying to find that balance with the sun risk for patients, cause I think that's the thing again, people are trying to find that balance with the sun, correct Um and um, and it really isn't a ton.
Speaker 3It, like I said before, it's not baking in the sun. So in general, there's a Dr Webb who's done amazing work, kind of figuring out exactly what this question is. Um, and in general, five to 30 minutes, so we're not talking a long time. Five to 30 minutes of midday sun and again, this goes against the, the academy's recommendation to stay out of midday sun. But midday sun is when you get your biggest bang for your buck with UVB. We don't need all this extra UVA. The UVB is what is really working on the immune system.
Speaker 3And so midday, five to 30 minutes, um, three days a week to about 25% of your body, your skin surface areas, so arms and legs or face, lower arms, lower legs although I like to cover the face in general but it doesn't take much skin exposure to get that 25%. That's going to keep you out of the deficiency range for vitamin D and we use vitamin D levels as a surrogate, as a marker for adequate sun exposure, because we don't really have better markers. But we know a lot about disease related to different levels of vitamin D. So using vitamin D as a marker of adequate sun exposure five to 30 minutes, depending on your skin type, where you are makes all of the difference. Three times a week midday is enough to keep you in that adequate range.
Speaker 3Um, it really doesn't take a lot and there are very, very cool um tools available online where you can actually get exact more. You know exact times based on where you are, what skin type you have, how much skin is exposed um and how much sunlight it gets during that season. Um to to get you know a thousand, I use a vitamin D and how long it would take to burn, and I can share those resources. But they're fun tools. But if you stay in that five to 30 minutes and use your judgment, with understanding of what your skin type is and risk factors, usually that's a good range to get adequate sunlight. And I think we're going to talk a little bit more later about the different you know oral dietary things you can do, lifestyle things that you can do and potential supplements that you can do if you fall into a higher risk category, and how you can support your skin in ways that go beyond just sunscreen use.
Speaker 2That's a great tease for our next podcast we're going to do together because for listeners out there, I'm sure a lot of you are maybe surprised that you know for a dermatology podcast that we're talking about the benefits of sun, but we're all about presenting. You know the pluses and minuses of everything that we all do and I think too, sometimes we focus on. You know the negative aspects of sun exposure. So hopefully you've been enlightened today about the benefits of sun and stay tuned for another podcast that I'm going to do with Katie to talk more about, as she mentioned, sort of diet and nutraceuticals as well for some protection. But before we kind of sign off for today, do you mind sharing with our listeners, katie, where they can find you online?
Speaker 3Absolutely so I'm not terribly active on social media. We do have an Instagram it's shine underscore dermatology and we are pretty active on social media. We do have an Instagram it's shine underscore dermatology and we are pretty active on our website in general, which is shine functional med medcom. So right now there's not a whole lot of other places online where we're at but um, but you can follow along and we'll keep those areas updated.
Speaker 2Great. Thank you so much. This is a fascinating topic, so I'm so excited to have you on for a few additional podcasts, so be on the lookout for those and stay tuned for the next episode of Dermot Trotter. Don't swear about skincare.
Speaker 1Thanks for listening to Dermot Trotter. For more about skincare, visit DermotTrottercom. Don't forget to subscribe, leave a review and share this podcast with anyone who needs a little skin care sanity. Until next time, stay skin smart.
