Why Some Sun Exposure Will Protect You from Deadly Skin Cancer

THE SUNHow does sun exposure relate to skin cancer risk?

The simplistic, popular story is that sunlight exposure has a linear relationship with cancer, similar to how we view smoking. None is safest and each additional minute in the sun will increase our chance of getting cancer. Many people (maybe most) therefore live in a world with danger lurking beyond every shadow, umbrella, overhang, and roof. You let your kid go outside without a layer of sunblock so thick he looks like he’s been smashed in the face with a whip cream pie, and you’re a terrible mother. And don’t even think about the beach unless you’re wearing a burqa. It’s even got a scary name: ultraviolet radiation. Radiation! Isn’t that the stuff inside nucular bombs?

The relationship between sun exposure and skin cancer is far more complex than you’ve been led to believe. While clearly too much sun is a causative factor in skin cancer of all types, it’s not clear what “too much” means. Is there a U-shaped curve where none is bad, some is good, and too much is bad again? What about other factors, like skin color, hair color, propensity to tan versus propensity to burn, and time of day?

We already know that living in areas that get more UV radiation seems to be protective against other types of cancers, like prostate cancer, lung cancer, colorectal cancer, leukemiabladder cancerpancreatic cancerbreast cancer, and lymphoid cancers (I probably could have kept going, but my fingers were getting tired).

Okay, but what about cutaneous malignant melanoma (CMM)? It’s not the most common kind of skin cancer, but it’s by far the deadliest. Is it worth the tradeoff if we increase our risk of CMM?

When we combine the estimated number of annual diagnoses for the cancers I just mentioned in the US, we get a staggering figure: 1,071,000. What about melanoma? 76,100. Incredible, huh? Getting adequate amounts of ultraviolet radiation (scary!) may very well reduce the incidence of cancers that are afflicting over a million Americans each year. Even if the dermatologists and sun alarmists are right and melanoma risk increases linearly with sun exposure and ultraviolet availability, the protection we get against so many other cancers (and the tan, and the sublime feeling of the sun on your skin) might make the tradeoff worth it. That’s clearly, objectively true, at least on the population level. Melanoma just isn’t as large an absolute threat as the totality of other cancers.

Every reader of this blog is likely aware of the importance of vitamin D in the body. The vital pro-hormone, which also comes in supplement form, helps regulate skeletal, cardiovascular, immune, hormonal, and dental health. A deficiency can cause rickets, osteoporosis, muscle wasting, and various hormonal deficiencies. Low levels are linked to heart disease, autoimmune diseases, all cause mortality, and many cancers. These are the systemic effects that get the most attention, but what if the dermatologists and sun alarmists were wrong, or at least a little misguided in their binary opposition to any and all sun? On the surface, it seems counterintuitive that an act that has so many proven anti-carcinogenic and health benefits – getting enough sunlight to optimize vitamin D levels – would increase our chances of getting another type of deadly cancer. It’s possible, but it’s odd.

And there are some other curious facts that muddy the neat, tidy relationship between sun and skin cancer:

Vitamin D (produced in response to UVB exposure) kills melanoma cells. Researchers posit that vitamin D levels around 70 nmol/L may be optimal for protection against melanoma.

There’s also the recent study that suggests smart sun exposure has beneficial, anti-cancer effects at the skin level. Contained within our skin cells are RNAs that do not synthesize proteins, called non-coding RNA. When vitamin D is produced in the skin cells, it triggers these non-coding RNA to go into protective mode. They reduce carcinogenicity and induce tumor suppression. It’s unclear whether oral vitamin D “makes it into” the skin to have the same protective effect. If anything, supplementary vitamin D will deliver the systemic benefits to bone, heart, immune system, and endocrine system thereby reducing the amount we have to produce at the skin level to get the desired anti-carcinogenic effect. But you still need some sun exposure to get it.

Okay, given what we know about vitamin D, it’s easy to buy that it can be protective to a point. Some sun is helpful. Cool. Surely, though, those who get the most sun get the most skin cancer. You have to imagine that outdoor laborers, lifeguards, and other people who spend all day outside in the sun, have way more skin cancer than indoor workers. Right?

It doesn’t seem to be the case:

  • “Recreational” sun exposure – weekend outings, vacations, and other forms of intermittent exposure to the sun – is usually associated with greater melanoma risk than chronic sun exposure.
  • “Occupational” sun exposure – the kind outdoor workers or other groups who spend lots of time in the sun on a regular, consistent basis – is associated with lower rates of melanoma. In fact lifetime sun exposure is associated with a lower risk of melanoma.
  • In Ireland, non-melanoma skin cancer is increasing among the young, urban, and affluent. The authors suggest that the young, urban, and affluent have more free time on their hands, and they’re spending it outdoors. Okay, but the biggest increases in skin cancer in this demographic are occurring in clothed body parts – the swathes of skin that get the least amount of sun exposure.
  • Body parts that get the most sun have the lowest rates of melanoma.

It actually makes sense that going from habitual sun avoidance (working inside all week, getting out on the weekends every once in awhile when you can find the time) to full-on sun exposure (vacation in the tropics, an all day beach excursion) would be bad for you. Indoor skin simply isn’t ready for high UV exposure, and it will burn more easily in response to it. Sunburning definitely increases the risk of melanoma.

Plus, indoor workers still receive UV exposure, just differently. They might see the sun in the morning, through the windows during the day, and after work in the late afternoon. Both morning and late afternoon sunlight have very little vitamin D-producing UVB; it’s almost entirely UVA. Midday sun (you know, the sun they tell you to avoid at all costs) is the only kind with appreciable levels of UVB. And even though office workers get modest levels of sunlight through windows, those windows filter out the UVB and leave only the UVA.

As explained in a 2008 paper (PDF), isolated UVA degrades cutaneous vitamin D while failing to produce any to replace it. So these indoor workers aren’t making any vitamin D and what little they do produce is being broken down from all the UVA they receive.

But wait: although UVA promotes melanoma progression, UVB initiates its formation. Animal models show this. And the connection between sunburns (which are caused by UVB) and melanoma supports it. So isn’t UVB the real problem?

As stated earlier, intermittent and excessive exposures of UVB (“recreational sun exposure”) which often result in sunburns are the problem. It just so happens that the people most likely to get recreational, intermittent, condensed sun are the people who work indoors and go most of the year with low vitamin D – from lack of consistent UVB and from excessive low level window-filtered UVA. People with occupational exposure are getting UVA and UVB in consistent doses, enough to keep the vitamin D levels topped off and nip any budding melanoma cells before they can progress.

How does all this translate to the real world?

Don’t fear a healthy base tan. Contrary to popular opinion, a tan isn’t “already too late.” People who tan well (as opposed to the sun-sensitive types who burn easily) have greater resistance to skin cancer and people who maintain a year-round tan have a lower risk of melanoma.

Avoid burning. Burning is still bad. It’s negative feedback from your body regarding your excessive exposure levels.

Go out at noon. This is when UVB and vitamin D production are highest. The popular advice “that sun exposure should be avoided for three to five hours around noon and postponed to the afternoon” is likely “wrong and may even promote CMM.” Another way to determine UVB availability: go out when your shadow is shorter than you.

Don’t go from zero to sixty. Don’t go from spending the past three months indoors to tanning for hours-long stretches. Work your way up gradually, minute by minute. Start small, especially if light skinned/red haired/blond.

Move around. Don’t “lay out.” You don’t want to expose a single body part to the sun for an extended amount of time. Go do stuff that exposes different parts of your body: garden, lift weights, hike, swim, that sort of thing.

Consider vitamin D supplementation. It delivers the desired systemic effects to bone, heart, immune system, and endocrine system, thereby taking a load off the skin, which can save some D3 for its own protection, and increasing your resistance to the sun. Anecdotes frequently report increased resistance to sunburns upon vitamin D supplementation.

Get your nutrition in check. There are many “internal” measures you can take to increase your skin’s resistance to sun damage. I outlined several of them here.

Get your sleep in check. Our resistance to the sun follows a circadian rhythm, with our defenses strongest in the first half of the day. So you might not want to go tanning after an all-night bender, nor do you want to get too much UVA-rich sun in the late afternoon when your defenses are down.

I hope I cleared up some confusion. If not, feel free to send along any questions.

Thanks for reading!

TAGS:  prevention

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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100 thoughts on “Why Some Sun Exposure Will Protect You from Deadly Skin Cancer”

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  1. You know, there’s been a few things I’ve done over the years that’s counter to CW: don’t stretch before your muscles are warm, you do not need 8 glasses of water a day, coffee is not the diuretic everybody tells you, don’t fear the sun: fear the sunscreen!

    Not sure if there’s some ancestral memory that told me these things, or whether I was just going against the grain (ha!), but lately there’s been a lot of evidence to support those viewpoints. Maybe, deep down, we should listen to ourselves more often?

    1. I agree, Cody. I never stretched before running–it didn’t feel good. Stretching a bit if I felt like it partway through the run, if something was a bit tight, that felt right. I ran for 32 years without injury. Same with the coffee and water. That always sounded nutty, that a 115 pound woman should drink 8 glasses just like a 300 pound man, or that coffee would dry you up. Never cared to force things.

    2. Ha! Pretty much coffee and wine are the only liquids I drink. Unless I’m actually thirsty and then I drink water.

  2. Nice! Stay in the sun as long as your body’s innate warning system kicks in – getting flush (and hopefully a little before). If you HAVE to go out for long periods then make sure to use FULL SPECTRUM sunblock. These two points are pretty critical for most people.

    1. Or once you reach that point, cover up. I’m still a little wary of slathering that crazy list of ingredients on my skin…

  3. how long should we be supplementing with Vit D before a week long trip to Mexico?

  4. Mark,

    with regard to maintaining a year-round tan and melanoma risk, you seem to have misread the conclusion of the study you link to:”Maintenance of an all-year tan provided no protective effect against melanoma” (“…after adjustment for tendency to burn.”) – Or am I missing something here?

    1. In addition, it should probably be mentioned that, while things appear to be paradoxical with regard to CMM, non-melanoma skin cancer risk seems to indeed be consistently and linearly linked to lifetime sun exposure – the curious case of the Ireland yuppies and their clothed body site-cancers notwithstanding.

    2. It doesn’t seem likely that someone with a strong “tendency to burn” would maintain a year-round tan, so I don’t see how they could “adjust” for this unless there’s some goal-seeking going on in here.

      For those of us who do burn, but who also tan if we get frequent short exposures which then protect us from burning if we get a longer exposure, it seems like there could be a protective affect, as well as the protective affect for all the other non-skin cancers mentioned…

      1. “It doesn`t seem likely that someone with a strong “tendency to burn” would maintain a year-round tan,…” – maybe so, but that doesn`t mean you can`t mathematically adjust for it. Still, I get where you`re coming from; the conclusion of the study seems counterintuitive to me, too. Alas, being counterintuitive isn`t necessarily synonymous with being wrong.

  5. Ever since I had my vitamin D levels checked (low–allergic to dairy–go figure!), and supplemented with enough D-3 to raise my levels into the 80’s, I haven’t had to wear sunscreen at all while outside mowing, pulling weeds, yakking it up with neighbors over the back fence, etc.

    1. Have you found a supplement that works. I supplement 4000iu a day and have my healthy fats in check and all that. Blood test still showed slightly low D3 levels. I can only surmise I am using low grade supps.

      1. 4000 IU/day probably isn’t enough for you. Vitamin D levels depend on a variety of things – age, general health, weight, etc. Some people just don’t absorb D as well as others, either from supplements or from the sun. Try upping your daily dosage to 8000 or 10,000 IU. You can take 10,000 IU every day just about indefinitely. I took 12,000 IU every day for well over a year with no harmful effects. I now take 8000 to 10,000 IU daily to keep my level around 75 ng/ml.

      2. Vince,

        what kind of Vit D you are supplementing with? Prefer the D3,not the D2!

        Where are your levels now, below 40ng/ml? How long did you wait between starting the supp and testing?

        1. I am using Nature Made D3 (cheap stuff from the grocery store). I don’t remember the exact level but I know it was lower than optimal, around 40 is what I think. The doc’s suggestion was try a different brand? Thanks for the comments, this article is well timed as it pours in NYC.

        2. Vince,

          either you did not wait long enough to get an equilibirum between intake and consumption of Vit D or you are simply taking not enough. 2-3 months would be a fair amount for that. If you are taking the pills already longer reach out for a higher dose, e.g. 6000 IU.

          What’s your weight? All my calcs are for the 140-180 pound range…so feel free to add proportionally for another weight!

          Actually you are at 40 (ng/ml I assume?) .What result had your initial measurement? What’s the timespan between those two lab tests?

      3. I take Biotics Research Bio-D-Mulsion Forte® (2,000 IU) which are emulsified drops that you put on the tongue & are absorbed into the bloodstream that way, therefore bypassing the digestive system. They are very well absorbed, so you don’t need too much. I used to take 2 drops daily (4000iu) & my vitamin D results came back as 115mg/mL (far too high!) I never go out in the sun, hardly ever expose any bare flesh to the sun and don’t eat fish or dairy due to allergies, so I found that hard to believe. Anyway I stopped the vitamin D for 2 months & tested again. The level had gone down to 88mg/mL which is still on the high side, so I left off supplements for another month & then started back taking one drop every other day (making it 1000iu a day) & tested again. The levels are now optimal but not excessive. However, I do find it hard to believe that I only need 1000iu a day, although I am very small, so maybe that is why? The other thing I wonder though, is if I have a polymorphism, so that although the level seems okay in the bloodstream, maybe it is not actually reaching my cells? However, when I was on the 4000iu a day, I was getting frequent headaches which I now don’t get which is a sign of vitamin D toxicity, but I also wonder if it is because I don’t have enough magnesium to support the D?

        1. I am 6’4″ ~200lb so not small. I have never heard of Biotics research, very interesting. I’ll probably up the dose on my D3 pills till the bottle is gone then look to switch to something a little more effective. Dr. Rhonda Patrick has really been stressing the importance of D3 on so many processes in the body (Magnesium too). I would definitely stress taking magnesium before bed every day.

  6. thoughts on tanning? say 10m a week for an office dweller?

    1. Go for a walk around your office’s neighborhood a few times a week at lunch man!

      1. I already do this, given I work in an office I’m fully clothed hence very little light exposure (I live in New Hampshire where it’s quite cold most of the time)

        1. I live in LA and I have the same same problem minus the cold. I can go for a walk at lunch time but only my face, neck, and hands are exposed.

        2. Same problem here in Michigan…especially this year.

          I guess that’s why I finding issue with Mark’s comment about “not laying out”.

          Mark said, “Move around. Don’t “lay out.” You don’t want to expose a single body part to the sun for an extended amount of time. Go do stuff that exposes different parts of your body: garden, lift weights, hike, swim, that sort of thing.”

          But when you gardening or hiking much of your body is covered or shaded by other parts of your body…when I hike my legs rarely get exposed to the sun…the most exposed parts are my face and forearms. And with swimming…if I’m actually swimming, my face is the only thing out of the water. Even a day at the beach, if you’re not laying out gets mainly your back, face, shoulders, chest and arms…the most regularly exposed stuff.

          Laying out exposes all of your body…not overexposing just some parts…and I would think that would help you get your Vitamin D faster and thus not need as much time in the sun versus activities that mainly expose your face and arms.

  7. Very informative article, Mark. I didn’t know that the UVA coming through windows broke down vitamin D in the skin. That fact alone is worth the article.

    As I was reading your article I kept thinking, “Well, I can’t avoid working indoors, and in Seattle sunlight is as precious as gold. What can I do?”

    Thanks for offering a solution at the end. I supplement with vitamin D, and I take fermented cod liver oil. I do not burn easily anymore, but then again I am cautious around sunlight. Your article cleared up a lot for me, and now I have a strategy for my very pale-skinned son.

  8. There can’t be much of a link between skin cancer and sunshine – I’ve had skin cancer twice yet live in the UK!

    1. …contended no one with a basic understanding of pathogenesis ever.
      (“There can`t be much of a link between lung cancer and smoking – I have lung cancer, yet have never smoked.”)

      1. It seems your understanding of pathogenesis is better than your basic understanding of humour.

        1. No problem! Self deprecating humour is quite a British trait I believe.


  9. I am extremely fair skinned. I have literally gotten a sun burn in the car in the traffic on the way home from work. Just not sure how to play this one…

  10. A moment of vanity here . . . no mention of wrinkles and age spots due to sun exposure 🙁

    1. YES. Thank you for pointing this out. I always make sure to get my limbs nicely exposed to the sun, but the face–never!!! It’s endocrine-disrupting sunscreen all day, every day. I am frankly annoyed that Mark never addresses the wrinkles issue (sorry Mark.) I’m not worried about skin cancer, but I don’t think anyone can assert that sun exposure won’t exacerbate wrinkles, though I’d love to be wrong about that.

      1. I can’t remember in which article, but I’ve heard Mark address this issue before. He said something along the lines of “definitely cover up the face if you are worried about wrinkles”.
        I usually prefer to wear a hat rather than put on sunscreen.

      2. I’ve been searching for the article for a while, but I really can’t find it. I was sure I heard him say that, but I’m starting to think I heard that somewhere else and I’m putting words in his mouth.

  11. From what I’ve read and personal experience, it is essential to get enough K2 when taking D. Somewhat hard to get K2 from food, especially if you don’t do hard cheeses. (I do eat them.) When I have supplemented with D3 without K2, I have gotten a bunch of kidney stones. Every time. Mark has written about K2.

    1. Also, sunlight on your skin is what turns cholesterol into sulfates, absolutely necessary for many, many cellular processes. Check youtube for Dr. Stephanie Seneff’s seminar on the subject. She is also an expert in the science of Glyphosates (Roundup) and their effects on living organisms. Dr. Seneff is an MIT scientist and a member of the WAPF.

      1. I recently listened to a podcast: Is Sulfur the Missing Link in Heart Disease and IBD? by Steven Wright. Steven interviews Dr. Stephanie Seneff.


        I thought this was very interesting – one of the better podcasts I’ve heard, lately (it’s a year old, though).

        I was drawn into listening to it based on the importance Dr. Terry Wahls has put on sulfer containing foods.

        I’m not throwing out my vitamin D supplements, but, it seems like my general attitude toward supplements has been a bit misguided.

  12. A while back I read what I thought was a crackpot theory at the time. the author felt that it was the fact that people were now wearing sunglasses that was leading to the higher incidence of skin cancer – he had some stats from Australia that showed the rise in skin cancer in relation to when sunglass use began and linked to sun exposure. Something in there about the pineal gland was not getting the natural light stimulation to trigger some kind of protective effect when the eyes get exposure to sunlight. The sunglasses block this exposure so the gland does not realize the intensity of the sun and while you still tan – or burn- the protective effect is not triggered. interesting to see if any basis for this.

    1. That’s news to me, but, I *have* quit wearing sunglasses. Except, I wear the orange ones at night.

      1. Interesting. The Inuit up in Alaska made sunglasses out of seal bone so they would not go snowblind.
        I own a sunglass shop myself, and I also use BlueBlockers at night, but I recently quit wearing the sunglasses during most of the day. I do know that many American Indian fisherman also went blind at a fairly early age from looking into the water too much. I would like more info. on this stuff!

    2. I read something similar but I only remember it in relation to sunburn not skin cancer. Still it would make sense.

      Oh do tell me this sun loving girl need not feel guilty about it. It certainly is good for the soul.

  13. I live on the coast or Northern BC, Canada, where we get very little sunshine (relatively speaking) and very short days in the winter. It definetely takes a toll on mood and sleep. How does using a tanning bed for frequent short periods of time compare to exposure to real sun. I would love to tan frequently but my husband is worried that short periods of intense sun is much more damaging than exposure to the sun. Have you found any studies on this? Thoughts?

  14. Thanks again Mark for a great topic. However there is no reference to melanin, the light scattering compound that is produced by melanocyte cells in the skin. Our bodies produce this pigment to protect from damage from over exposure. More here: https://en.wikipedia.org/wiki/Melanin

    ZnO is a natural light scattering, melanin mimicking, compound that works as good if not better than any patented/expensive compound in commercial sunscreen. Or modern world has us escaping winter in Montreal to the Mayan Riviera. Sunscreen is necessary for extremes. I agree that consistent gradual exposure is best to let our skin protect ourselves naturally.

  15. > Get your nutrition in check.

    If the re-emerging metabolic (vs. faltering somatic) theory of cancer turns out to be correct, an LCHF diet with ample ketone precursors may well be highly protective against cancer of all kinds, including skin.

  16. Is there a relationship between omega 6 consumption and the propensity to sun burn?

    Anyone have any experience here?

  17. I was looking at that article you linked. I liked how the comments to her rant were almost universally negative. It seems that the word about Vitamin D is getting around. 🙂

  18. I just have to say: As soon as I read the opening paragraph and scrolled down enough to the comment for tweeting, I did it! Without reading the REST OF THE ARTICLE!!! Did I just spread a dangerous word…like a cancer? 😉 That article Mark linked to (you’re a terrible mother!) is so misinforming. It’s sad what people read for their news on what is good for us and what is not: and especially in this case, how self-critical we need to be because we’re just “irresponsible” if we “send [our children] off into the sun’s damaging rays] without applying sunblock. Laughable.

    I posted a comment and linked to THIS article! 🙂 Thanks for all you continue to do Mark (and Minions!)

    1. My son had blonde hair and blue eyes but can tan fairly quickly at the beginning of the summer. The only HORRIBLE burn he got was in Mexico when a concerned relative put sunscreen on him. He got such a horrible burn from the chemicals it felt like he was on fire and there was sand under his skin, and he didn’t even get any sun exposure. Grrrrrrrr, ask a parent before putting on sunscreen people!!!! Oh well, he knows to not allow anyone to put it on him now.
      I now make him go barefoot as much as possible in the warmer weather and we build his color carefully so he doesn’t have to have any kind of burn from either the sun or chemicals.

      1. I now make him go barefoot as much as possible in the warmer weather

        Freedom. Let him try it. He might like it.

  19. I burn easy, so in the Fall I start with the tanning beds, and build myself up to 15 minutes a week (high power beds). This gives me a good base, and I then enjoy my Mexico trips a lot more. I can take my shirt off for half and hour or more everyday and have fun on the beach.

    Tanning beds help a lot with SAD. I used to live in Juneau, and that place never gets much sun, but winter is really tough. Tanning beds really cheer you up. (So do natural light tubes over your desk, counter, etc.)

    I have never found supplementing with any amount of vit. D to be helpful with sun protection, though higher doses do make my skin ruddier.

  20. I saw a significant difference in the way my skin reacted to the sun last summer (my first summer after being mostly primal). It was amazing. I tanned so well that people at work asked if I was still working full time (because apparently I looked like I played outside in the sun all day). Granted, I did spend a lot of time outside after work, and I live in Anchorage so the sun is still pretty strong from 5-7…but still, I really think my healthy eating habits had a lot to do with my ability to tan and not burn. Even on a trip home to Nebraska I didn’t burn. Just another reason to be primal! Hurray!

    1. Stacie, a lot of us Primal-ettes have had that experience with the sun. Nice. I sat out in the sun for quite a bit last summer and nary a burn on any day. I go to AZ to visit my folks and no burns there either. I’m going to try to tan a bit more thru the tanning bed if we are still here in the cold dark north during fall/winter this year. I really do better in a warm and sunny area, my dream is to move soon…..
      Did you hear that Universe? Let’s get that worked out…. a move to the warm sunny (insert a nice sunny place where good primal food is plentiful).

      1. Me too! After only 6 weeks primal eating we went on a family holiday and my husband and I both tanned quickly and easily, then held the colour far longer than usual on our return. This was quite literally groundbreaking for me as I had given up all hope of ever getting much of a tan. I read a theory on one site that it is partly down to the coconut oil in the diet, no idea if this is true…

        1. I do not take coconut oil but have experienced much better tanning since supplementing with vitamin D3. I believe what is happening is that when you are very deficient, your body ‘wants’ to absorb as much possible sunlight and therefore does not create melanin to block it. In addition, vitamin D3 up-regulates several systems in the screen that are protective against UV radiation.

  21. This post was quite interesting to me as I have been fighting ocular melanoma for almost five years now. I grew up in the upper midwest without an inordinate amount of either sun protection or sunburns. I do have light blue eyes, one of the common risk factors for developing a melanoma on your retina.

    When first diagnosed my vitamin D levels were so low (9) that my docs made a point of telling me to get more sun exposure (and to supplement). I’ve read studies that show that people fighting cancer generally have better outcomes with more sun exposure/vitamin D, so I try to get outside every day and don’t make a particular effort to cover up or use sunscreen, unless I will be in a rare high-risk situation for sunburn, like a day at the beach.

    I also don’t put sunscreen on my kids except for the higher-risk situations, because there are other more common cancer risks on both sides of our family.

    1. I started tanning in January this year to gradually build up tolerance. OK. I live in California. I haven’t used sun screen yet and haven’t burned even though I was sometimes out for 3-4 hours in mid-day April.

      I’ve also stopped using soap to wash — just cold water. I wonder how that affects your sun tolerance?

      1. Mercola had an article that basically said that the Vitamin D is formed in your skin oils, and that if you take a shower with soap and hot water, you’ll be washing all that precious Vitamin D off. Wait overnight to let the oils soak into your skin.

    2. Sunshine is life itself. Without it nothing would live, period. Sunscreen use is more the result of successful marketing propaganda than actual necessity.

      I grew up in Colorado, where there’s plenty of sun. As a child, I ran around all summer in skimpy clothing, minus sunscreen because nobody used it in those days. Sometimes I burned, but mostly I just got brown. To this day I never use the stuff because it’s just plain nasty. I detest smearing all those chemicals on my skin. I have had the occasional not-too-serious sunburn over the years, which never amounted to anything except an unsightly case of peeling skin. I have never had even the slightest hint of anything that could become skin cancer.

      For people who are fair-skinned or don’t tolerate much sun, or if you’ve gotten enough sun and are turning pink, have the good sense to cover up and leave the chemicals on the shelf, Your body doesn’t need that gunk.

      1. Thank you for this link. Yes, the new drugs are amazing. I just finished a three month course of ipilimumab a few weeks ago, with basically no side effects, and as of last week the scan showed very good news. If the ipi doesn’t ultimately work there are still three or four other newly available drugs that were not on the market when I was diagnosed. I am fantastically lucky that I got this disease when I did and not ten years ago.

  22. I believe that consumption of seed oils, which are extremely inflammatory, and often rancid contribute to the formation of skin cancer (and all other cancers).

  23. I am red-haired, fair-skinned, have autoimmune problems and live in Australia! For years I did the avoid sun at all cost regime which resulted in Vit-D deficiency. I improved my diet (went Paleo) and deliberately spent short periods of time out in the sun (without sunscreen) every day. My last blood test showed Vit-D levels in the normal range.

    What I take from this article is that regular short-periods of sun exposure during the middle part of the day is the way to go. That’s what I’ve been doing. If I need to walk/work in the sun for longer I wear a hat and cover up.

    1. I’m autoimmune in Australia, too! Photosensitive. I find I’m much less bothered by the sun since I’ve been eating AIP paleo (much more pared down that primal).

      I’d never go out in the middle of the day – have always been told it’s too dangerous. I’m going to give it a go throughout winter and spring, see if I can build up a tolerance without kicking off a flare.

  24. Here’s the thing though. I’m a life-long resident of Southern California. I’m blond, too. I hate sunscreen. I’m 49 and have sun-damaged skin. I’m wrinkly, splotchy and get frequent pre-cancerous lesions. People I know from North Dakota have such creamy perfect skin compared to me. Obviously all my sun exposure hasn’t been all that benign.

  25. I am not a standard office worker (I am a massage therapist), but I do work indoors (and in my case, in a windowless room)…. My solution to sun exposure, when it is warm enough at least is to take my lunch down to the park one block down from the clinic. I sit in the sun and eat it and enjoy the peace and the fresh air.
    Can’t do this in the depths of winter in Calgary though, but last week and the early part of this week it has been warm enough to sit out.
    I don’t tan deeply, but I cannot remember the last time I got burned (as a kid I think…) I just go a pale biscuit colour and stay there. And I haven’t used sunscreen in years.
    For the person who asked about wrinkles – I suspect you are more likely to get wrinkles around the eyes at least from squinting in the sun – I always wear sunglasses to protect against that. I am 44 years old and have very few wrinkles, in fact I have been complimented on my “beautiful skin” and been mistaken for being at least 10-15 years younger than I actually am. A lot of the time, if you get wrinkles will be determined by how much elastin you have in the connective tissue in your skin – more elastin means fewer wrinkles, and incidentally fewer stretch marks for ladies who get pregnant.

    1. The sun often gets blamed for causing wrinkles, but in reality it’s more a function of heredity. However, too much sun can definitely make matters worse if you’re already inclined in that direction.

  26. But what about babies? Where I live, it’s a criminal offence to put your baby under direct sunlight any amount of time before 6 months old. (I’m exaggerating but seriously, it’s almost as if it’s criminal). Is it true that a baby will have vit D reserves if the mother’s diet was adequate?

    1. A breastfed baby gets vit d through the milk. HOWEVER pregnant mothers in Australia are now routinely tested for vit d deficiency after a study showed something remarkable like 70% of pregnant women were vit d deficient. That’s how my deficiency was picked up, he’s nearly 18mo old now but I still supplement daily, between 6-10k iu.

  27. HAH, I got in an argument with someone yesterday about sun being good for you, not bad, but didn’t have the arguments other than “Don’t burn” and “vitamin D is good”… no more arguments need. Copy/paste link.

  28. Always feel better physically and mentally with a bit of sun. I would go for a ‘little and often’ approach to sun exposure if I didn’t live in the UK – it’s more like 8 months off, 4 months on! Difficult to keep a natural base tan…

  29. Yea, I’m a redhead in Seattle. I too take issue with the “don’t lay out” instructions. Today, for instance, is a rare beautiful spring day, the sun clear & high. But it’s not all that warm. I will lay on my protected back porch for about 10 minutes, in shorts & a tank top, with my face & hands covered since they already get way to much sun. This is my best option, because after that I’m just gonna put on pants & a sunhat & a shirt with the sleeves rolled slightly up. There’s really nothing to be had in useful exposure in that, the normal outfit. Also I downloaded an iphone app yesterday called dminder – still working it out. But it’s kind of clever. You put in your age, blood level of D or supplement level, what you’re wearing (shorts, bikini, whatever), it tells you from your location when the sun is at an angle to give you D. you start a timer & it counts off how much you’re getting, then an alarm goes off to tell you to get the heck out of the sun before you burn. I don’t know if this is a keeper, but it was interesting to see that it thought I only needed about 8 minutes.

  30. Very provocative article on the sun’s influence on cancers and melanomas, I am a 71 year old active man who has spent all of my life outdoors either working or hiking or kayaking or some other activity and I have maintained a seasonal tan to the extent that one can do in the Midwest as the seasons change. I have noticed a change since I moved to the Panhandle of Florida in 2001 in that my forehead and my nose, in the past couple of years, do not seem to want to tan but rather those skin areas tend to turn red and burn. Repeated use of SPF 30 sun block doesn’t seem to hinder the burn effect nor does daily exposure over a period of days/weeks cause the burn to peel and “turn into a tan”! My forehead area is blotchy with small areas of burn sprinkled in with a normal colored tan. My nose simply has not been able to hold a tan for the past 2 or 3 years. Understand that I wear shorts and T-shirts almost throughout the entire year here and one would suppose that being tanned practically the whole year long would be some kind of deterrent to burning after the tan is dark and been almost permanent for months on end.

    Is there any suggestions for what to do since I don’t seem to be getting back to my “normal” mode of tanning on my face and I do not want to risk skin problems on my nose or forehead in the future. I don’t wear hats as I have a problem with headaches for some reason within a half hour of donning a ball cap or straw hat or anything that fits on my head that is tighter than a knit watch cap. And, since I spend alot of time on the water kayaking, I really do not feel that a hat will stop much of the reflected rays off the water, that’s maybe an old farmer’s tale but I definitely do feel the difference in intensity of the rays of the sun when I am out paddling.

    Thanks for any hints or tips from those who may have found relief from this problem, I am presently using a prescription sunblock called, Vanicream Sport SPF 35 which was prescribed to me by a dermatologist at our local VA clinic. Oddly enough, the active ingredients in the sunblock are 3% Octinoxate and 11% Zinc Oxide which I can remember using as a life guard in my teen years to plaster on my nose while up “in the chair” on bright afternoons. We had no clue ZO was a sunscreen back then, we just thought it looked “cool” to have a white coating on our noses as we sauntered around the pool spinning our whistles on our index fingers!! Back then the chicks seemed to dig it!! Ha! The innocense of youth!!

  31. As a melanoma survivor I find this post completely infuriating. You are wrong. Any change in the NATURAL color of your skin. … the color your skin is meant to be ,the color you are born with, is SUN DAMAGE and means you have hurt your skin! There is No SUCH THING as a healthy tan or a”base tan.” Just because your skin can tan doesn’t mean you should. Always protect your largest organ.

  32. Marko, interesting article and lots of common sense stuff. Most of it seems to fit that old stodgy and true rule “all things in moderation”. Of course in the good old U S of A we generally think “if a little is good…more is better”. Or, we go to our health professional who says “none is best”.
    I was intrigued by the reference to Sun Glasses introduction and an increase in Cancers. I believe, intuitively that your eyes are your indicators for Sun exposure. Blue eyed and trouble being in the bright sun? Maybe that is telling you not to be in that much sun… Brown eyes and never feel even squinty in the sun? perhaps you also have darker skin and tan easily? In any case Sun glasses and Sun screen seem a bit “un-natural” to me. It’s “not nice to try and fool Mother nature”… I am going to increase my Vitamin B (un-naturally I guess..) as this Northern Michigan gray is not allowing much Sun for another couple months.
    Keep up the good fight Mark. -rodriquez

  33. I’m still confused by this. I’ve been following CW for my entire life because I’m fair, freckled and have red hair, light eyes, precancerous moles, and I live in southern CA, I’m a dermatologist’s dream patient. I was religious about sunscreen and now at (almost) 33 I can see how much better my skin has fared than my peers who tanned. It’s definitely not hereditary for me, my mom’s got very wrinkled skin from growing up tanning and living by the beach.

    So I am still wanting to apply (natural zinc based) sunblock daily, but worry I’m not getting enough vitamin D. I burn less easily since going Primal but I still burn, freckle, and get more moles if I go out and sit in the sun for more than ten minutes, even with sunblock. A base tan would really wrinkle me up, I’m sure.

    From an ancestral health perspective, I figure I’m not evolved to live in such a sunny climate. My ancestors were adapting to getting weak sun for only part of the year. So I can’t believe it’s okay for me to go out and try to get more exposure or as much as someone with darker skin.

  34. Go out at noon? GASP!!! Instantly I’m reminded of that sticker that was prominent when I was a kid. It showed a sun with sunglasses and said, “From 10 till 3 stay away from me!”

    But I always feel best after spending a day in the sun.

  35. The problem with the sun and me is all the sunspots or stains on my face. I prefer to put on an EWG sunscreen like Thinkbaby and avoid the sun in the middle of the day. I do my gardening later and get my vit D thru the rest of my body…legs, arms.
    Does that sound OK?

  36. with Irish parents that have had basal cell carcinoma and malignant melanoma, not convinced sun is healthy for me. It’s hard for me to tell how much sun is too much, I burn so easily. But that being said, had a golden tan when I was a kid.

  37. i am fair skinned, of irish heritage, and grew up in the caribbean- before the invention of sunscreen. if there were white people on the island with skin cancer i never heard about them or saw them. my father wore a hat and a t-shirt to the beach to protect his bald spot and his shoulders. we all wore t-shirts if our shoulders felt burned. then he came home one day with a new product- PABA. that is what he said it was. he slathered it on his bald spot and shoulders and ditched the hat and t-shirt. and he got skin cancer. on his bald spot and shoulders. i have always thought that the cancer came from the sunscreen product and not the sun.

  38. As usual, the frustrating part is that there is nothing clear, it’s all kind of muddled & you do what you can with it.
    – check out an old farmer sometime. My grandfather’s face & neck was brown & leathery, if you saw him without his shirt (rare in the extreme) his torso skin was pale white & elastic. So obviously sun exposure will cumulativly age your skin, which is a bummer.
    – As for high sun killing melanoma, it makes total sense that evolution would have found a way to protect us from the sun, which we have been in a LOT before electric lights.
    – on the other hand, we all know stories of people who’ve had skin cancer spots removed in their later years. What’s up with that? What’s up is that if you have a kid by age 15, then you’ve got grandkids at age 31. Nature is done with you. Go die already. Many of our health problems today are simply age related. We didn’t used to live long enough to suffer from many of them.
    – I’m a redhead. ZERO tanning here. Yet I get the vite D argument. So what to do? Quit freaking out over the thought of laying in the sun for hours. I downloaded an app for timing my sun need based on my latitude & time of day & it says right now, if i’m taking 1000mg as a supplement, then I only need 10 minutes a day in the sun. Fine. That’s a long way from committing to BBQ.
    – What about that pineal gland argument? What about that british study saying your burn more if you wear sunglasses because your brain isn’t getting tru info about the brightness so it doesn’t put up defenses as well?
    – ok then, what about the things saying protect your eyes or you get sun damage on the retina?

    My personal takeaway is – ok so I only need 10 minutes a day this time of year. That’s not so drastic. I don’t feel I’m risking my hide too much. Also I’m going with the sunglasses. We have had 4 days of brilliant sun in Seattle & I’ve had a migraine every damned day. Some people have….I don’t know I guess problems in the brain & how it handles light, & for me, bright sun can make me get a migraine, so the tradeoff of wearing sunglasses is worth it.

    And at night I use my mexican retin-A. Because as a midlife woman, raised on sugar & white bread, heading into the wrinkly years, this is yet one more very tricky path.

  39. Research shows, those Melanom patients with the lowest Vitamin D Levels, have the biggest depth of their cancer spots and the most metastatic stadium. Their the least treatable.

  40. And here I am in the tropical region. 8am-onwards sun exposure will make you perspire, irritated then pass out like a dead meat. I get to maintain a healthy diet and exercise along with my squalene supplement to boost up sun protection and immune system but it’s just sad I can no longer play and walk under the sun.

  41. Thanks Mark for sharing some positives about sun exposure. And here I am in the tropical region. 8am-onwards sun exposure will make you perspire, irritated then pass out like a dead meat. I get to maintain a healthy diet and exercise along with my squalene supplement to boost up sun protection and immune system but it’s just sad I can no longer play and walk under the sun.

  42. what about carcinoma?
    one seems more vicious tho but i’m confused about the difference

  43. I think this is really interesting. I’ve long noticed that people who are protected from later in life from sun exposure seem to suddenly start growing numerous skin tags and lesions, which often turn into cancer. This was the case with my grandmother, who had previously spent her life in the sun before being moved to a nursing home where she got none. I’m now noticing the same thing with my mother, who only just recently started protecting herself vigilantly from the sun. She too suddenly has all kinds of skin growths popping up. Yet, I vacation at a beach resort every summer which has a high population of seniors and I’ve noticed those who are constantly out in the sun seem to have no such issues. I developed a personal theory that if you’ve spent time out in the sun during your lifetime, the worst thing you can do is hide from it later in your life!

    1. Numerous skin growths appear with age. Just wait a few and you will start finding them too. Seborrheic keratoses, skin tags, angiomas, the list goes on.

      As for skin cancer appearing later in your grandmother…. She is old. Cancers often take time (and multiple serial genetic mutations) to arise. It’s why age is a risk factor for common cancers like chronic leukemia, breast cancer, lymphomas, prostate cancer, colon cancer, and on and on and on.

      Old people are inside more often. Older people get wrinkles as they age. Is it the sun avoidance that causes wrinkles too? Nay. Correlation vs causation, yo.

      Science is NOT the enemy. It’s kinda all we can actually trust. Don’t fear science.

  44. re. sun burn,

    i once read a study that people who have had some mild sun burn are less likely to develop skin cancer.

    (don’t ask me — a layman for citation)
    but in terms of hormesis, it seems to makes sense)

  45. Wow thanks for the shadow advice! I was looking everywhere on internet trying to find how to determine when was the better time to sunbathe according to your latitude and it’s really hard to find.

  46. A couple other folks already mentioned this, although what about carcinoma, Mark? It might not be as deadly as melanoma, although it’s still cancer, and considered malignant while it exists. I spent a ton of “recreational” time in the sun in college, and afterward ended up with a basal cell carcinoma (BCC) spot that had to be surgically removed.

  47. The World’s Only 6 Time Cancer Survivor Savors A Life Well Lived

    Andrew Kuzyk

    Each year right around Christmas, I post a simple message to thousands of folks I’ve never even met, telling them essentially, “I’m still alive.” My oncology doctors told me years ago that “I’m the only six-time cancer survivor in the World” Within days, a tremendous chorus comes back, 175 voices, 500. Many ask, “How did you survive?” They sometimes begin, “Tears are flowing”. A few answer back in kind; “Right there with ya”. It’s now eight years and I am still on this Earth.

    Surviving cancer once, twice, maybe three times may be rare, but six times is simply unheard of. What is in a human being to survive is beyond explainable? We have all heard about survival instinct, but until you are put into a survival situation you have no idea what you are really capable of. I am truly a remarkable fighter who has beaten cancer SIX times, also suffering from Lupus and Alzheimer’s I have defied any and all expectations to reach my 53rd birthday! I am still fighting despite enduring a multitude of cancer operations, including two my surgeons thought I would not even survive. I have every wicked surgery scar to remind me of my 6 multiple battles with deadly cancers.

    Being a feisty father & grandfather from McDonough, Georgia I have fought through so many medical issues it is mind boggling. My health issues began when I was diagnosed with an acute cancerous appendix at the ripe age of 17, I required emergency surgery just before the organ would have ruptured, causing fatal infection to my body. Appendix cancer tends to be rare, affecting an estimated 600 to 1,000 Americans each year. Unfortunately, appendix cancer often remains undiagnosed, like mine was until my emergency surgery. Appendix cancer mysteriously has no known cause. At the time I had no idea I would tangle with cancer yet again soon. I had always been a physically active person. A few months after the bout with appendix cancer, I had several episodes of pain in the upper right quadrant of my abdomen. I thought I may have gallstones and decided to avoid high-fat foods because a high fat diet increases gallstone risk.

    Later that year, however, I started having steady nausea that became constant. I was also having some coronary artery issues and had was scheduled to have several stents surgically inserted. It was in the recovery room after the cardiac stent procedures when I felt unbearable pain in my midsection. My doctor ordered an abdominal ultrasound, which showed irregular thickening of the gallbladder walls. “They couldn’t rule out carsinoma” A surgical specialist reassured me that “cancer was highly unlikely”. “He had done thousands of gallbladder surgeries and rarely saw gallbladder cancer. He said, “It was very rare, and if that were the case, you would probably be dead by now”. Well, my surgeon removed my gallbladder laparoscopically, but the news wasn’t good. Unfortunately, the pathology came back showing T2 gallbladder cancer. I fought the disease by having my cancerous bladder removed before the cancer could invade my entire system. “The statistics for gallbladder cancer are not very reassuring. I went into surgery hoping to live two years.” My wife and five chihuahuas were very supportive during my treatment. “My wife was a blessing to me, always making sure I stayed positive and being so supportive”.

    Two years later, I went to a dermatologist to have a mole examined. I have a condition called displatic nevi syndrome, meaning I have a higher potential for skin cancer than others. My moles are darker than average and tend to turn into the deadly malignant melanoma. Two shave biopsies were performed and pathology tests showed very deep Breslow depths with tumors present in deep margins as well as peripheral. An oncology team referred me to a general surgeon after reviewing my poor prognosis. With deadly stage 4 malignant melanoma, a wide excision surgery was the only radical treatment known to attack and remove the cancer. It is a miracle in itself to survive a stage 4 cancer attack. The cancer left my back looking like a cruel battleground of scars. The surgeon cut as deep as possible, but still did not know if he got it all. I would have to be examined for the rest of my life for the possible return of the deadly malignant melanoma cancer.

    “The toughest one was the renal cell carsinoma “kidney cancer” surgery.” Having a kidney removed was the most difficult of any of the 6 cancer surgeries” Just one year previous, I was forced to have my left leg surgically sawed in half and almost amputated because of infection, to remove a malignant bone tumor lodged in the center of my leg bone. The recovery period for these two surgeries was intense and lengthy. My body now looks like a battlefield with scars everywhere. A major skin graft was taken from my upper thigh tissue to cover the wide excision scars on my back. Somehow I fought through these cancer surgeries through prayer and perseverance. “After one operation, I opened my eyes and the surgeon actually told me the operation was over, but he wasn’t certain if I would pull through, due to serious infection concerns. My 6 multiple cancer diagnoses don’t appear to be based on genetics, just dumb luck.

    Two years after the grim Stage 4 diagnosis, I confessed to a close friend that the doctors had said I realistically only had two years to live, tops. I had kept this information to myself because if I were to say it, then it’s true. I now continue to hold my breath, now that I am now past that deadline. I have spent the last 8 years holding my breath, as I enact every New Year’s resolution, past and future. There’s a small subcategory of people with Stage 4 cancer, it turns out, who live for years after being diagnosed. This group constitutes about 2 percent of all cancer cases. Doctors can’t predict who will fall into this category.

    I told them “I’m a fighter”. Somehow I have managed to fend off the infection and slowly recovered. I pulled through because of my fighting spirit, belief in God and the skill of the surgeons who performed the procedures to remove the deadly cancer. I now fight a myriad of daily health issues including Alzheimer’s disease, diabetes, lupus, heart disease, peripheral neuropathy, and needing both knees surgically replaced. I now live with my wife and chihuahuas in a small basement as the camper we were living in burned down recently, we are barely hanging on to survive these days.

    “I’ve had it tough with the cancer and other ailments I guess” I cannot really do much at all these days. I consider himself a cancer “frequent flyer” being operated on now for 6 bouts with different cancers. “how many people can say that?” I try not to let my physical and mental conditions run my life, but it takes everything that is within me to get through another painful day. If you want to help a friend diagnosed with cancer, just be there. Friends can’t make the fact that you have cancer go away. They can’t make it all better. They can, however, help you feel safer. “when your scared, it’s important to know that someone is there”.

  48. If some sun exposure is good for you, why have I seen some older people with leathery looking tanned skin? Is it because they use tanning beds, and tanning beds are not as safe, or is there some other reason, or is it both reasons?

  49. Thanx for the article on Sun exposure will protect your from skin cancer… i am 60 now but lived on the lake ( indiana) growing up and loved water everything.. i have olive skin and never ever used sun tan lotion. I have seen a dermatologist regularly (which i recommend- of which you neglected to mention to do) and have had @a dozen spots cut out on various parts of my body.. nothing melanoma! I was wanting information about letting myself still keep a light tan in the summer at 60ties plus. I still slalom ski and did so competitively when i was younger. I wear a rash guard top an shorts bathing suit to cover more vulnerable areas. My first skin cancer was on my nose. I do suggest sun tan lotion on tops of shoulders, nose, feet, and breast chests to avoid burning your skin. I agree don’t lay out in the sun.. play in the sun. I will take much from your article to help guide my exposure as i still want to be in the sun at 60 plus. Thank you.

  50. Thanks for a really good article. The general UV alarm seems so similar to all-fats-are-evil alarm of the end of the 20th century and all-carbs-are-evil alarm that is still in force today. So I’ve been searching around for evidence that we aren’t, in fact, designed to live like mushrooms.

    I hope it’s not taken the wrong way, but I thought I’d offer that “nuclear” in the article is mispelled “nucular” in the second paragraph. Not trying to be a spelling freak, but I’d want someone to let me know if I was the author so it doesn’t throw people off.

  51. I live in the Appalachians, on the side of a mountain, in the middle of the forest. It’s beautiful and amazing and I love it here, but getting out in real sunshine is a challenge, especially morning sun. By the time the sun has passed the trees and landed in my yard, it’s much closer to noon than morning. What options are there besides supplements (which I take already) to get sun exposure. Will a trip or two to the beach or tropics each year be helpful? Thanks!

  52. Really helpfull, but I have a question.

    I see a lot of use in going outside when the sun is out an all, but are there any benefits to going outside when it’s not? Does the sun penetrate the clouds?