Do seed oils block cholesterol to vitamin D? Vitamin D as sunscreen Sunburn resistance of people who don’t eat seed oils
Summary by Google's LLM
In this video clip from Low Carb Down Under, Dr. Paul Mason presents a theory linking the consumption of industrial seed oils to a higher susceptibility to sunburn
Key Arguments and Claims:
- Vitamin D as Natural Sunscreen: Dr. Mason states that the body naturally vitamin D as a protective shield against UV/UVB radiation damage to DNA, rather than strictly for bone health
- The Cholesterol Connection: He references Ancel Keys’ historical “Seven Countries Study”, highlighting a data point that individuals with higher sun exposure had lower blood cholesterol levels. He explains this occurs because the body uses cholesterol to synthesize vitamin D
- Interference by Plant Sterols: He argues that plant sterols (phytosterols) absorbed from dietary seed oils interfere with normal cholesterol chemistry, specifically disrupting the skin’s ability to synthesize vitamin D
- Anecdotal Evidence: While acknowledging the evidence is largely anecdotal, he points out that a vast number of individuals on ketogenic internet forums report a noticeable resistance to sunburn after completely eliminating seed oils from their diet.
The premise for his argument is “humans produce vitamin D as a sunscreen”.
Which…what?? No. Humans produce melanin as natural sunscreen, not vitamin D.The next premise is that phytosterols interfere with “a lot of processes”, and “maybe Vitamin D production is one of them”.
Well yeah, maybe…or maybe not, who the fuck knows without any evidence?And his evidence that eliminating seed oils from diet leads to resistance to sunburn is (which he admits) anecdotal.
“I’ve heard dozens of people tell me this.” lol.For the love of god (and especially your children), eat what you want, but don’t tell people it has magical powers and lets them avoid skin cancer, unless you have really solid medical proof from large studies on your side.
The premise for his argument is “humans produce vitamin D as a Sunscreen”
Which…what?? No. Humans produce melanin as natural sunscreen, not vitamin D.
Yes melanin protects us from sunlight, but what’s your source for vitamin D not being protective against sun damage?
what’s your source for vitamin D not being protective against sun damage?
That’s not how evidence works.
If you claim Vitamin D has an effect that was unknown before, you need to provide evidence for that.
Without evidence, the default is “no known effect”.psud is not making a claim, the effects of vitamin D protecting against sun damage is something we already know about. It is not hitherto unknown. Please see my other post on the topic.
Since your claim goes against the scientific literature, he is correct in asking for your sources, so we can verify them.
The premise for his argument is “humans produce vitamin D as a sunscreen”.
The argument is that plant sterols interfere with cholesterol function, impacting systems all over the body including vitamin d production.
Well yeah, maybe…or maybe not, who the fuck knows without any evidence?
https://doi.org/10.1159/000337881 -
Effect of Plant Sterols on Vitamin D Absorption
Cholecalciferol (vitamin D 3 ) is either obtained from the diet or produced photochemically in the skin from 7-dehydrocholesterol, which is produced in relatively large quantities from cholesterol in the gut1 and is accumulated in the skin [1]. Since plant sterols and stanols alter micelle formation and decrease absorption of cholesterol, it is possible that absorption of fat-soluble nutrients including fat soluble vitamins is also affected.
The objective was to examine if plant sterols interfere with the absorption and possibly the synthesis of vitamin D3 . A randomized study was conducted in 40 apparently healthy adult volunteers aged 18–60 years who received orally either 25000 IU vitamin D 3 (group A, n = 20) or 25000 IU vitamin D3 together with 2 g plant sterols (Group B, n = 20). Levels of Vitamin D 3 , 25-hydroxyvitamin D 3 , calcium, phosphorus, magnesium, cholesterol and parathyroid hormone were measured in blood taken immediately before consumption of Vitamin D 3 and at 12 h, 24 h and 168 h (7 days) after administration of Vitamin D 3 . Serum vitamin D 3 concentration increased significantly in both groups at 12 h and 24 h and 25-hydroxyvitamin D3 at 168 h after the consumption of vitamin D. Group B had lower vitamin D 3 levels 12 hours and 24 hours after administration and lower 25-hydroxyvitamin D 3 levels at 168 h after administration.
Hence, inhibiting the absorption of cholesterol may also affect the absorption of vitamin D 3 . Long term (> 4 weeks) administration of sterols is needed to investigate the impact on Vitamin D absorption and consequently its metabolism.
It’s well known seed oils will lower LDL cholesterol, this is a direct demonstration of their impact on the bodies hormone system, and cholesterol functioning. This is not a good thing.
For the love of god (and especially your children), eat what you want, but don’t tell people it has magical powers and lets them avoid skin cancer,
Cancer happens all the time, right now at this very second both you and I have cancer cells in our bodies - typically not enough to overwhelm us and we survive (typically). The magical power is keeping the body healthy so immune function is excellent, so that the homeostatic machinery can do its job.
unless you have really solid medical proof from large studies on your side.
https://doi.org/10.1111/joim.12496
Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden cohort
Results Women with active sun exposure habits were mainly at a lower risk of cardiovascular disease (CVD) and noncancer/non-CVD death as compared to those who avoided sun exposure. As a result of their increased survival, the relative contribution of cancer death increased in these women. Nonsmokers who avoided sun exposure had a life expectancy similar to smokers in the highest sun exposure group, indicating that avoidance of sun exposure is a risk factor for death of a similar magnitude as smoking. Compared to the highest sun exposure group, life expectancy of avoiders of sun exposure was reduced by 0.6–2.1 years.
Conclusion The longer life expectancy amongst women with active sun exposure habits was related to a decrease in CVD and noncancer/non-CVD mortality, causing the relative contribution of death due to cancer to increase.
More sun exposure more cancer, but longer life… so doing everything with a focus on avoiding all types of cancer may (may) be counter productive. You will note Dr Mason didn’t tell you to not use sunscreen, and didn’t tell you to stop avoiding the sun, he only talked about vitamin D function and how carnivores report not getting sunburn - it’s not a recommendation for behavior.
The study you linked is about the effect of phytosterols on Vitamin D adsorption from an oral source.
It says nothing about Vitamin D production from sunlight.
And the study involved a single dose of Vitamin D given, to 40 people.Long term (> 4 weeks) administration of sterols is needed to investigate the impact on Vitamin D absorption and consequently its metabolism.
So the study itself says “for actual evidence, we’d need more data”.
The study you linked is about the effect of phytosterols on Vitamin D adsorption from an oral source. It says nothing about Vitamin D production from sunlight.
The point was to demonstrate plant sterols have a impact on the bodies cholesteral systems including vitamin d production and absorption.
So the study itself says “for actual evidence, we’d need more data”.
Literally every paper ever written says that. We always need more studies, that’s the nature of curiosity. In fact professors have to admonish grad students not to add that to papers since its just filler at this point.
I’m not sure what your core thesis is: Vitamin D is not relevant in sun exposure?
https://doi.org/10.1016/j.jid.2017.04.040 -
Oral Vitamin D Rapidly Attenuates Inflammation from Sunburn: An Interventional Study
The diverse immunomodulatory effects of vitamin D are increasingly being recognized. However, the ability of oral vitamin D to modulate acute inflammation in vivo has not been established in humans. In a double-blinded, placebo-controlled interventional trial, 20 healthy adults were randomized to receive either placebo or a high dose of vitamin D3 (cholecalciferol) one hour after experimental sunburn induced by an erythemogenic dose of UVR. Compared with placebo, participants receiving vitamin D3 (200,000 international units) demonstrated reduced expression of proinflammatory mediators tumor necrosis factor-α (P = 0.04) and inducible nitric oxide synthase (P = 0.02) in skin biopsy specimens 48 hours after experimental sunburn. A blinded, unsupervised hierarchical clustering of participants based on global gene expression profiles revealed that participants with significantly higher serum vitamin D3 levels after treatment (P = 0.007) demonstrated increased skin expression of the anti-inflammatory mediator arginase-1 (P = 0.005), and a sustained reduction in skin redness (P = 0.02), correlating with significant expression of genes related to skin barrier repair. In contrast, participants with lower serum vitamin D3 levels had significant expression of proinflammatory genes. Together the data may have broad implications for the immunotherapeutic properties of vitamin D in skin homeostasis, and implicate arginase-1 upregulation as a previously unreported mechanism by which vitamin D exerts anti-inflammatory effects in humans.
Yes, its oral, but it demonstrates that vitamin D is a necessary part of the bodies sun exposure mechanisms. i.e. its produced on demand to treat the damage the sun is doing to the skin.
Humans produce melanin as natural sunscreen, not vitamin D
Please see
https://www.explorationpub.com/Journals/em/Article/1001225
While UV-induced photoaging causes a detrimental impact on the skin, the UVB induced cutaneous synthesis of vitamin D protects the skin from various stresses.
The paper covers some of the mechanisms, it’s a good read and will improve your understanding of our body. Melanin isn’t the only protective factor.
https://pubmed.ncbi.nlm.nih.gov/23069805
We present data to show that 1,25(OH)(2)D(3) protects skin cells from at least three forms of UV-induced DNA damage, and provide further evidence to support the proposal that a reduction in RNS by 1,25(OH)(2)D(3) is a likely mechanism for its photoprotective effect against oxidative and nitrative DNA damage, as well as cyclobutane pyrimidine dimers.
Not open access, so you’ll have to find the full paper yourself.
i would love to see a study on keto vs carnivore sun protective effects
I think the body stops making Vitamin D from the sun when it already has enough to prevent overdose.
So can it really protect you after a certain point?
I think the body stops making Vitamin D from the sun when it already has enough to prevent overdose.
Citation please.
So can it really protect you after a certain point?
The body is all about homeostasis - Carnivores report not getting sunburned after long term adaptation, we don’t know the exact mechanisms actually. There is lots of speculation about photosensitizing chemicals, cholesterol function, etc. Regardless of the exact mechanism the thesis is simple: modern eating has a impact on our ability to endure sun exposure and repair damage.
I read on healthline that it’s almost impossible to get too much vitamin D from the sun. So I thought the body has to reduce the rate of production at some point when it has enough.
Carnivores report not getting sunburned after long term adaptation
Interesting. Hope they uncover the mechanism soon.
There is a possible mechanism. Since melanin increases UV absorption, as you darken due to exposure you will need more exposure to produce the same amount of vitamin D.
healthline is not a primary source.
Hope they uncover the mechanism soon.
No money in nutritional approaches to health, so don’t hold your breath!
Rule of thumb. Never listen to someone who uses
“Just asking questions”
Rhetoric. They’re doing it that way to defend themselves in court or to hide their ignorance.
When does Dr Mason say that?
“Perhaps vitamin D synthesis in the skin maybe one of those functions.”
This isn’t a sentence from a place of evidence backed science, this is a string of probably connected things that Dr. Mason should know isn’t the same as a proven idea. In fact he says its anecdotal, but he is presenting it in a way that the listener can come to the conclusion that cholesterol makes vitamin D without having to site anything.
If this were a scientifically backed idea he could have said but didn’t would follow.
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“The Keys survey showed people with higher vitamin D had lower cholesterol.”
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“A second study was done and found X and Y”
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“Thus confirming that cholesterol is used to make vitamin D”
But that isn’t what he said. He only cited part of what sounds like a much larger study and is then extrapolating based vaguely on anecdote.
Could it also be possible that people who spend a lot of time in the sun simply consume food with higher vitamin D content and they’re in the sum all day because they’re mostly agrarian or some sort of labor economy so they’re working out which lowers cholesterol levels with a normal diet? Yes, but we don’t know more than that based on this talk.
If he’s honest, then this is an interesting start point to do science, but as it stands he’s just using human psychology to convince people of his position without needing good evidence.
Do you see how “perhaps” is different from “just asking questions?”
It is not anecdotal that vitamin D and cholesterol levels in the body are related by the Kandutsch-Russell pathway: https://www.jbc.org/article/S0021-9258(20)41142-1/fulltext
The anecdotal evidence that Dr Mason is referring to is the observed phenomenon that people on the carnivore diet do not sunburn as easily as the people who are not.
Please don’t misrepresent the content in this community.
Do you see how “perhaps” is different from “just asking questions?”
No. Its the same rhetorical move its just different from the more aggressive “just asking questions”
Please don’t misrepresent the content in this community.
I’m trying not to, but this is a short clip without any context or further readings.
I want you guys to have better educational materials.
This guy says a lot of things with coincidental or anecdotal evidence at best and that’s not good evidence when also trying to position oneself as an academic expert e.g. “Dr.” In the name. Dr. Mason should know better if the Dr. Is worth anything.
Take the criticism or don’t, but this is a relatively small push back to the carnivore idea.
If there’s more, better science on these claims, then they should be included, referenced within the talk. Something! Maybe this is just an out of context clip, but that doesn’t make the argument better. It’s fundamentally a bad line of reasoning that only means something to people deep in the weeds of carnivore food science. How was I, an outsider, supposed to know about the paper you’re citing? How can I know he knows about it?
Dr Mason is doctor enough to call out what is not scientifically proven. The only parts of this very short segment from a longer presentation that isn’t demonstrated yet but science are:
- That people on low carb diets who avoid seed oils suffer less sunburn than those who eat seed oils; and
- A mechanism for seed oils to block the effect of vitamin D.
He clearly flagged those as anecdote and supposition so I’m not at all sure what your problem is.
The very short summary is “isn’t it interesting that lots of people in this population claim to not get sunburnt, since this thing that other population eats and this population don’t is known to stop parts of this system in the body, I wonder if it also blocks related thing”
There is nothing controversial there, it’s a clearly stated hypothesis
The other mods have pointed out I haven’t been seeing your replies due to a weird federation block issue that I’ve resolved. Looking at your comment history in this community I need to remind you have our Rule 4 - I would reply to the earlier comments, but they didn’t federate to me.
Be respectful of other diets, choices, lifestyles!!!
You can disagree, you can dislike, you can provide counter arguments but ad hominem attacks against people (including the people making the articles and content) isn’t what we do in this community.
I’ve made no ad hominem attacks so far as I can tell.
I’m criticizing rhetorical style and listing my reasons why.
The closest I can see to ad hominem was putting “Dr.” In quotes, but that was just for emphasis on the title since I didn’t know if asterix would work e.g. Dr.
Also, my apologies for any confusion as I do have 2 accounts. I promise I’m not tying to ban evade or anything. I just forgot I switched at some point.
I’m trying not to, but this is a short clip without any context or further readings. I want you guys to have better educational materials… Maybe this is just an out of context clip
Here is the full talk https://www.youtube.com/watch?v=Kvh4D_osFXs
I’ve made a post on it for you - https://startrek.website/post/41025554 He does reference the papers that support his statements in the slides.
I can tell you from personal experience posting that almost nobody will actually watch a hour long lecture, but they will watch a 30s short.
Take the criticism or don’t, but this is a relatively small push back to the carnivore idea.
The sunlight talk really isn’t about carnivore, it’s about the benefits of sunlight exposure. The very minor part of the talk discussing photosensitivity on different diets is more of an aside then the focus.
How was I, an outsider, supposed to know about the paper you’re citing? How can I know he knows about it?
You can ask, you can watch his full lecture - but coming in swinging puts people on the back foot.
I was in error, the short clip is actually from https://www.youtube.com/watch?v=NVqNO8rgYKk a informal 5 minute talk he gave at a keto conference (preaching to the choir so to speak), but it is based on his more formal lecture I discussed above.
Honestly I hate youtube clipping, it confuses everything.
I did watch the full lecture you linked, but I did notice it was different from the short clip.
Its a good talk and well cited. It also matches sources I had found independently with the help of my fiance who has a degree in chemistry and in nursing (alas, I am just a history fan who likes to argue).
But I’d like to point out I did say
It’s fundamentally a bad line of reasoning that only means something to people deep in the weeds of carnivore food science.
Does my original point make sense?
I do think there’s interesting science here and I honestly and truly don’t want you guys getting caught in grifter style clip farming, rage baiting, circle jerkings. Dr. Mason seems to be a pretty good source, but his newer content is slipping into this sensationalist format of communication.
A lot of his newer stuff has lines like “what mainstream medicine doesn’t want you to know!” “Are you smarter than you’re doctor?” Which I admittedly haven’t seen those videos yet, but that’s a red flag that a lot of carnivore content seems to lean on.
I get it, that’s how the algorithm works, but I think good information can thrive by just being packaged well.
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