Dear Mark: Primal Sun Protection and Stigmasterol Stability

Sun ProtectionFor today’s edition of Dear Mark, I’m answering two questions. First up concerns the effect going Primal has on your skin’s resistance to sun damage. While there isn’t any specific research examining ancestral eating and sun damage, several lines of evidence suggest a protective effect. Second, what’s the deal with stigmasterol, AKA Wulzen anti-stiffness factor? The WAPF says butter and cheese and milk are the best place to get it, but that pasteurization destroys it. Is this really true? And how does fermentation affect stigmasterol?

Let’s go:

When I was younger, I burned in the sun quickly. Now that I’m older and paleo, I can stay shirtless in the sun for at least an hour at high noon without a tan or sunscreen in spring without burning. I’m very watchful because of history, but I never come close to burning. Is there any evidence the paleo diet provides protection from the sun?

There’s some decent evidence that going Primal helps protect your skin from the sun. RCTs showing added protection on a Primal way of eating don’t exist, but we have good evidence that doing the things typically characterized as “Primal” helps.

Eating colorful, polyphenol-rich plants: Whether it’s the lycopene in tomatoes (especially cooked ones), the proanthocyanidines in red wine, the flavanols in dark chocolate, or  pretty much any colorful, polyphenol-rich spice, fruit, or vegetable, each is shown to help protect us from the kind of free radical damage in UV rays.

Eating saturated fat and monounsaturated fat: Compared to PUFA, both SFA and MUFA (via a photoprotective metabolite of oleic acid) confer protection against skin cancer in animal models.

Eating dietary cholesterol-rich foods: In what must have blown lipid hypothesis-embedded researchers’ minds, a study from the late 70s found that the more dietary cholesterol a mouse ate, the longer it took for UV-induced skin cancer to develop (PDF). This makes sense; cholesterol in the skin reacts with UVB to form vitamin D, thus acting as a “buffer” against sun damage. If you’re eating eggs with any regularity, you’re probably improving your skin’s resistance to UV.

Eating salmon and shrimp: The pink color indicates the presence of astaxanthin, a photoprotective “keto-carotenoid” that krill-consuming marine animals carry in their flesh. You can also go straight to the source and eat krill oil.

Eating adequate omega-3s:  One study out of Australia—land of skin cancer—found that adults with the highest serum concentrations of DHA and EPA had the least “cutaneous p53 expression.” When your skin is in danger of damage from the sun, p53 expression is upregulated to protect it. The fact that p53 expression was low suggests that the skin wasn’t in danger; the omega-3s were protecting the skin and reducing the “perceived” (and real) danger. Acute intakes of EPA reduce the inflammatory skin response to UV radiation.

Drinking coffee and/or tea: Both the caffeine content and the phytochemicals present in tea and coffee have shown protective effects against sun damage.

Also note that it’s not just about what you eat. It’s about how you sleep, too. Our skin’s resistance to UV damage follows a circadian rhythm. We seem best adapted to sun exposure during the morning/early afternoon. It’s also quite probable that a bad night’s sleep, or several, will open you up to increased sun damage, since our ability to repair UV-derived damage depends on a well-functioning circadian rhythm.

Any of that stuff sound familiar? I’ll bet it does.


Amylase and Wulzen anti-stiffness factor (stigmasterol), normally found in raw milk, butter, and cream, are reportedly destroyed by pasteurization. Do either of them survive the fermentation process to any extent in the making of raw milk cheese?



Stigmasterol is a plant sterol, a compound similar to cholesterol with benefits for joint health. It’s also called the Wulzen anti-stiffness factor after Rosalind Wulzen, who discovered a mysterious component in butter oil that restored the health (particularly of connective tissue) of ailing animals (PDF). Though it’s the most famous source of stigmasterol, dairy isn’t the only place to get it. The only reason it’s present in grass-fed dairy is because the animals obtain it from the vegetation they eat.  It’s also found in neem (a medicinal herb used in India), blackstrap molasses, and sunflower fat, just to name a few.

I’m not even sure stigmasterol is destroyed by pasteurization. The Weston A. Price folks have always claimed it does, but I haven’t seen any real references. One recent study subjected sunflower oil-bound stigmasterol to 180 °C for up to 3 hours. By the end, some but not all of the stigmasterol had been destroyed. Pasteurization subjects milk to 71.1 °C for just 15 seconds, far gentler than what the sunflower oil stigmasterol was subjected to. You could argue that oil-bound stigmasterol is uniquely resilient, but dairy-bound stigmasterol is fat-bound, too. I don’t see why it’d be any different.

Fermentation? A survey of various goat and sheep dairy products, including fluid milk, fermented cheeses, cream, and butter found that stigmasterol was present in nearly every product studied (PDF). It’s safe to assume your fermented raw cheese will have some stigmasterol remaining.

Overall, what I found suggests that stigmasterol probably isn’t destroyed by pasteurization, let alone fermentation. Even if it is, there are plenty of other places to get stigmasterol. I’ve spoken highly of blackstrap molasses in the past, so go for that.

Don’t get me wrong: I still prefer raw dairy, provided it’s safe, grass-fed, and from a quality source. But I’m not sure stigmasterol is a reason to focus on it.

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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26 thoughts on “Dear Mark: Primal Sun Protection and Stigmasterol Stability”

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  1. I’ve brought good Irish butter back into my diet, and with summer in swing, have been enjoying kefir as well. Of Slovak origin, I have that olive coloring that takes immediately to sun and turns deep bronze. I have found though, that with my primarily paleo diet, I don’t have that one week of burn or sensitivity at the beginning of summer. Last week I was under the direct South Dakota sun doing service work on the Pine Ridge reservation. I’m deeply tanned, but not burned. Used some sunscreen, of course, but my body responded really well. I’d like to think it’s diet!


  2. Stigmasterol

    THIS is why I hang my arthritic neck in shame..I’m allergic to dairy. I must have a cruel god somewhere…

    1. re: I’m allergic to dairy.

      Have you isolated why? Chances are you are already grain-free, but if not, a lot of people report that various allergies, including bovine dairy, remiss some time after ceasing to consume grass seed products (zonulin-provoked leaky gut is a prime suspect).

      For bovine dairy, experimenting with sources known to be beta casein A2 might be worth a try. Not trivial to find in North America.

      Caprine (goat) or ovine (sheep) dairy is also worth a try, if you can find either. Having your own goats is optional (we do, and we pasteurize, btw).

  3. I’ve always thought pasteurization is less dangerous then the raw milk advocates claim. Not that I have a problem with raw milk, if you can get it legally then by all means. Raw milk actually could be better for lactose intolerants due to the lactase enzyme in raw milk. Me personally I’m not a milk fan period, the only dairy I use s grass fed butter and pasture raised heavy cream. I think people get pasteurization and homogenization mixed up, even the so called professionals. I recently saw a video of a man named doctor Axe and he’s some sort of a health guru and he was claiming ultra-pasteurization destroys(or oxidizes) the fat present in the dairy. Ultra-pasteurization is heating the milk to 280 degrees for 2 or 3 seconds. Most fat present in dairy is of the saturated and monounsaturated variety. The smoke point of these fats are well above 300 degrees and would have to be sustained there for a considerable amount of time. If anything I think vet-pasteurization is more dangerous, sure it’s at 145 degrees but for 30 minutes. Raw milk can be beneficial to those with lactose intolerant, but other then that raw dairy is just a scam in the sense of it being any healthier.

    1. I wildnt say scam. Don’t you think there are any probiotic benefits? Also, something definitely changes in another way. Drink a gallon of raw, whole, grass-fed milk and tell me why it is green when it comes out of your body! Gallon challenge really surprised the shit out of me!

  4. re: You can also go straight to the source and eat krill oil.

    Inasmuch as that’s immediately followed by a mention of DHA&EPA, people need to know that krill might be fine as a source of astaxanthin, but it’s a spectacularly uneconomical way to get a useful dose of Omega 3 DHA&EPA – and I define useful dose as more than 2 grams (2000mg) per day, and more typically above 3g/day, at least 1g of which is DHA.

    I used to sunburn badly on SAD and even Zone. On my present diet (which has considerable overlap with Primal), that problem simply vanished.

  5. Was happy to see as I was reading down the list of protective foods that I already consume most of them regularly. I’m lucky in that I have a great deal of tolerance to sun exposure before my skin gets damaged. I had never heard of sun resistance being linked to circadian rhythm and I find that quite fascinating.

  6. So would napping in the sun increase sun damage resistance?

  7. I’ve always tanned pretty easily and rarely burn, but since going primal I can say I tan even faster. I use zinc oxide for protection if I’ll be out for a long time, but even if I forget (like today…in a bikini by the pool as I write this) I never burn. Now I just need to work on the sleep thing!

  8. If stigmasterol can survive boiling in molasses I don’t see how heating during pasteurization could destroy it.

  9. As a ginger person working in the hot sun of an airport ramp, I really wish I could find the holy grail of sunburn resistance. Alas, nothing but sunscreen works well.

    I do make sure to eat a pretty steady and diverse array of polyphenols though.

    1. Try astaxanthin, 4mg before heading out then 4mg in the evening. It’s great for a lot of things. I’m a ginger too and I started using this and I can go for long periods in the sun and not get burned. I still get red, but I recover a lot faster and I still try to avoid too much sun. Check it out. Make sure you get the natural stuff.

  10. Hey Mark? Could you do something about how to incorporate blackstrap molasses into the diet? Everything I try is disgusting.

    1. Everyday at work I have a few cups of black tea with milk, (I’m english). I find if I put in up to half a teaspoon it improves the flavour, any more and and the molasses flavour comes through a bit strong. For me it really didn’t suit the flavour of coffee.

    2. Make barbecue sauce! Puree a sweet onion, add a can of tomato paste, a splash of vinegar and a few tbs of blackstrap molasses and let it simmer and thicken down until it holds onto a spoon. Its great with cheap lean cuts of pork. Blackstrap molasses is also a great way spike the flavor of tuber mash and butternut squash.

  11. I have 100% noticed a better response to sun exposure since going primal. Being a….how do I put this?….super white individual who surfs in San Diego, I used to get down right crispy even when using sunscreen. Now I eat primal/paleo and supplement with asthaxanthin and I rarely burn.

  12. I was the guy wearing SPF50+ and still suffering sun irritation and/or burn. I actually now believe that the chemicals in the sunscreen were a major part of that irritation.

    Since going primal I can actually get a tan without any irritation or burning. I no longer ever wear conventional sunscreen, I’d rather find some shade from the midday sun. I avoid vegetable oil like my life depends on it, eat tonnes of cholesterol rich foods and supplement Astaxanthin.

    If you can quantify SPF as a multiplying factor against your innate protection, then I’ve gone from 2 hours tops with SPF 50 to a full day (8 hours) with no sunscreen at all, that’s a 200x improvement!!

    Having looked up the chemicals in most sunscreens I’d never put that stuff anywhere near my children who are also 99% primal, instead we use raspberry seed oil and shade, they’ve never even been slightly burned. Although friends and family often shake their heads in disapproval at me while they slather their children in poison… Go figure!

    1. My family took a trip to Mexico and one of the aunts took it upon herself to “help” by putting that spray sunscreen on my son, he immediately got a HUGE chemical burn,worse than any sun burn ever could be, and we suffered for weeks after that. We now just put on some SPF 8 at the beginning of summer and the rest of the summer is great.
      It’s horrible for little ones to suffer from that junk. His little skin was so red and burned and it felt like sand had gotten under the skin as well. We tried EVERYTHING we could think of to reduce the effect, he knows now to NEVER let people put any sunscreen on him. That, of course, was before we went primal in our eating.

      1. Yeah at school they’re always keen to poison your kids with sunscreen not to mention the food on offer in the cafeteria. Not sure how I’ll tackle that one yet!

        I saw one incident recently doing the rounds on Facebook of a child that got “sunburned” despite wearing SPF50, to me it look more like a chemical burn than sun burn.

        Considering skin cancer is massively on the rise despite the heavy promotion of the importance of sunscreen makes the whole theory sound like nonsense to me! When you realise out many sunscreen ingredients are on the known/probable carcinogen list things start getting a little clearer. It’s all quite scary really!

    2. Raspberry oil? That’s really interesting, I’ll have to look into it. I have a nasty reaction to sunscreen so I’ve just been using the hypoallergenic stuff when absolutely necessary.

  13. I noticed since adding a tablespoon or two of coconut oil to my coffee every day, that even when I get super red, I don’t burn even without sunscreen or any hair on my scalp. Even when I’m not particularly adherent to Primal-ness.