Mark Bell's Power Project - The Vitamin D Lie: Why Supplements Don’t Work Like Sunlight

Episode Date: January 21, 2026

Full Episode Drops Monday, January 24th, 2026Sun avoidance has quietly become the default, and it’s doing real damage.In this clip, David Herrera breaks down why constant sunscreen use in low UV conditions can backfire, and why popping vitamin D pills isn’t the same as making vitamin D from sunlight.Follow David:@davidherrera1119Special perks for our listeners below!🥩 HIGH QUALITY PROTEIN! 🍖 ➢ https://goodlifeproteins.com/ Code POWER to save 20% off site wide, or code POWERPROJECT to save an additional 5% off your Build a Box Subscription!🩸 Get your BLOODWORK/TRT/PEPTIDES! 🩸 ➢ https://marekhealth.com and use code "POWERPROJECT" for 10% off Self-Service Labs and Guided Optimization®.🧠 Methylene Blue: Better Focus, Sleep and Mood 🧠 Use Code POWER10 for 10% off!➢https://troscriptions.com?utm_source=affiliate&ut-m_medium=podcast&ut-m_campaign=MarkBel-I_podcastBest 5 Finger Barefoot Shoes! 👟 ➢ https://Peluva.com/PowerProject Code POWERPROJECT15 to save 15% off Peluva Shoes!Self Explanatory 🍆 ➢ Enlarging Pumps (This really works): https://bit.ly/powerproject1Pumps explained: https://youtu.be/qPG9JXjlhpM?si=JZN09-FakTjoJuaW🚨 The Best Red Light Therapy Devices and Blue Blocking Glasses On The Market! 😎➢https://emr-tek.com/Use code: POWERPROJECT to save 20% off your order!👟 BEST LOOKING AND FUNCTIONING BAREFOOT SHOES 🦶➢https://vivobarefoot.com/powerproject🥶 The Best Cold Plunge Money Can Buy 🥶 ➢ https://thecoldplunge.com/ Code POWERPROJECT to save $150!!➢ https://withinyoubrand.com/ Code POWERPROJECT to save 15% off supplements!➢ https://markbellslingshot.com/ Code POWERPROJECT to save 15% off all gear and apparel!Follow Mark Bell's Power Project Podcast➢ https://www.PowerProject.live➢ https://lnk.to/PowerProjectPodcast➢ Insta: https://www.instagram.com/markbellspowerproject➢ YouTube: https://www.youtube.com/markbellspowerproject

It's like shocking to me how sun avoidance has permeated people so deeply. Like, you know, even my girlfriend and her friends, like, she goes out, when she goes outside in the winter, low UV here in Sacramento, UVs at like two or three. And I see her putting on sunscreen. I'm like, whoa, whoa, whoa, whoa, whoa. Or UV isn't like at five or six. Right now it's at two or three. She's like, well, you always put out sunscreen when you go out.

So I'm like, whoa, whoa. And then I asked her, how about your friends? They do this shit too? Or she's like, yeah. And it's like, barely. any UVA outside and you're still using sunscreen. Yeah. Yeah.

So now you're going to make yourself potentially autoimmune. Potentially, well, for sure, UV or not UV, vitamin D deficient. Yep. Sex hormone deficient, right? Because those are interlinked into that. You need UV to make vitamin D. Yeah. You need UV to make sex hormones.

You need UV to make neurotransmitters, right? So you're going to dispose yourself or predispose. to expose yourself to all of the conditions associated with that. We know that low vitamin D predisposes you to autoimmune conditions by a large margin. If you're female, Hashimoto's is probably one of the most common autoimmune conditions that a female can get and it goes sky high

when you compare it to vitamin D levels of people. So then people just start taking vitamin D pills. But it doesn't work that way because the vitamin D receptor is intertwined at the mitochondrial membrane. Right? So it's like a brake or a gas pedal at the energy production part of your body, right?

Yeah. And so it's intrinsic that that vitamin D interacts there, but oral pill doesn't do the same thing. What about dietary vitamin D? The, that's what I would call a supplement. Okay. Right. Like so even from like a fish or from.

Right. Now fishes are a little bit different. The reason why is because their vitamin D is stored in omega-3s, right? Whereas you pop a pill, that's a seed oil. That's going to be soybean oil probably. Right? And so you're popping vitamin D with an inflammatory oil versus an anti-inflammatory oil. And more importantly, DHA, omega-3s, are incorporated into cell membranes.

Remember what I just said about vitamin D. The vitamin D is at the membrane level of the mitochondria. Yeah. Well, if you pop it with a seed oil, then you're going to effectively change where it goes. It might not go to the right vitamin D receptor. It might activate some, but not all. Can you get like a false sense of security

by altering things with supplements that then therefore alter things on your blood work? Yeah. and see it all the time. I think you're healthier than you're like you're, so I get a vitamin D test and mine's 80. I'm like, yeah, but I've been just smashing like vitamin D pills. Yeah, the common one is this.

If you are smashing vitamin D pills and your vitamin D comes back in 80, I can almost guarantee you that one of two things is going to come back out of whack. Either your LDL cholesterol is gonna be too high or your DHA is gonna be too low. Right? The reason why is because vitamin D comes from LDLD

cholesterol. That's the molecule that's being interacted with by UV light. It's being sulfated and turned from a fat soluble molecule into a water soluble molecule and then making pre-vitamin D and all of those things. Well, if you take vitamin D and you don't go outside, well, what's the LDL cholesterol going to do now? Nothing. It's just going to build and build and build. The reason why it's going to build and build and build, you know, because most people will be like, well, yeah, but normally a feedback loop means that if I'm taking vitamin D, the demand for vitamin D should go down and my LDL should sort of self out. I'm like, yeah, but it doesn't just turn into vitamin D.

It also turns into pregmelo and DHEA. And if you're not going outside, you're not going to turn it into those either. But those are going to be low. That's why I said one of two things is going to happen, probably both. You're going to have low DHA because you're still not going outside and you're not sulfating that cholesterol molecule to go down the line towards DHA. And you're still making vitamin or LDL because LDL is not dictated by the food you eat. it's dictated by the liver.

The liver produces it. And the liver still is getting the signal from your sex hormones. Hey, you're low on sex hormones. Yeah. So the liver is going to go, well, crap, I guess I'm not doing a good enough job. I guess I need to make more LDL. Because it doesn't understand

that you're not interacting with UV light. It's still getting a feedback mechanism of low sex hormones. Yes. Right? And so this is part of the communication, highway of the body, right? The circadian mechanism

is not just I interacted with sunlight. That's kind of all you really need to know that what it does is it sets switches at different intervals on the track at the same time. So everybody's on the same page.

So questions since we're on the top with vitamin D. What are there, is it positive if somebody were to take X, I use a vitamin D, let's say 10 or 20,000, but they also get sunlight.

Was there positive or a negative? And of course, all of this stuff is individual, so there might be some other things. But what if somebody, they're like, they're taking vitamin D and they're making sure to get outside during the morning, midday, and evening? I would say that it could turn out okay.

It could, right? And what I'm saying is, what are your sex hormones doing? Right. Because if your sex hormones are still tanked, then you have no business taking vitamin D and you need to exploit more sunlight. Got it.

Now, my question would be, why are you taking the vitamin D if your sex hormones are good? Like, at that point, what I call is chasing numbers. You're chasing the number on the panel. And that, for that individual, might not be a good thing, and I'll explain.

The vitamin D receptor is at the mitochondrial membrane. That dictates energy production. Yeah. There is such a thing as too much vitamin D. Right? Now, for a natural person doing everything naturally, that number of natural vitamin D being made is probably somewhere in the 120s, 130s, something like that.

But I mean, that's somebody who spends 14 hours outside every day basically naked, right? But that means that they need to lower electron transport chain because they're spending so much time outside. So the vitamin D receptor being where it's at, when there's a large amount of vitamin D, Remember the effect that we talked about it? When you get a lot of sunlight, you tend to eat less.

Yes. Well, that's a vitamin D receptor mediated response. So you might be dosing vitamin D to the point where you're inducing that effect, but you actually might run yourself into an energy deficit unknowingly. Oh, wow. Because it's lowering electron transport chain output by just overstimulating the vitamin D receptor. Yeah, yeah. when you're not actually getting all of that ATP production from sunlight.

Okay. Right. So the answer is there could be a situation where it works out okay. Yeah. General rule of thumb, it probably doesn't work out that way. Got it. Right? Because if you actually were getting enough sunlight to make sex hormones and then somehow

you're still wanting to take vitamin D, it'd probably be okay for a month or two, right? But long term, probably not. Right. So I tend to either do one of two things. Exploit natural vitamin D production to the maximum of your capabilities during the summer and then get a test in the fall. And if you didn't make enough vitamin D, and here's a crucial part, you need to get a vitamin D binding protein test

because different mitochondrial haplotypes do different things with vitamin D. For example, an uncoupled haplotype might make a crap ton of vitamin D and sequester it very quickly with the vitamin D binding protein. So your vitamin D number at the end of fall might be 40 or 50. And you're like, man, I was thinking it'd be going to be way higher. I got a lot of sunlight over the summer. Well, maybe your body just sequestered it because your haplotype actually dictates that, hey, winter's coming up.

We need to sequester this so that it can be released slowly throughout the winter. Kind of what happens to me. My vitamin D is actually usually a little bit higher in the wintertime. Mm-hmm. It's like, boggled in my mind. And I was like, well, probably because you have high vitamin D binding protein. Right. So that's what I'm saying.

It's not, it's, you, there are, there is never one thing for one system. It's almost always two or three, usually five or six, right? And, you know, all you got to do is look at a graph about all the biological processes and it looks like a mess, right? And that's because that's why the circadian mechanism exists, because the same switch, sunlight, right? It's the same switch that's been happening for 3.8 billion years. Turns on hundreds of thousands of different track switching mechanisms depending on the wavelength of light that's interacting with you.

And to your point, your haplotype, you know, because think of it this way. Think of making coffee, right? You can affect the taste of coffee with the same being by changing the filter. You can also affect it by the super. speed that it filters through. That's your genetics. You're the filter.

The coffee beans the same, the sun. Yeah. Right. So the input's always the same. I mean, changes throughout the season, but it's always the same, you know, year after year. But you're the filter, and the filter changes the effect of the end product

depending on exactly your unique makeup. Right. So he might have higher vitamin D in the summer because he got, or I mean in the winter, because he got a lot of vitamin D in the summer, but it's not going to show up in his vitamin D test in the summer because he's sequestering it all waiting to release it in the winter

versus probably you and me, I have ridiculous vitamin D in the summertime. Mine gets like to 98. And in the winter, it drops pretty significantly. It drops down to the low 70s. That's still great vitamin D numbers. Right. Yeah. Yeah. But, you know, there's a large 20-point swing, right?

So I know that if, If I only get my vitamin D to 50, I'm screwed in the winter. Yeah. Whereas for you, 50 in the summer is probably ideal, right? Because it's going to climb in the wintertime. This episode with David Pereira dispelled so many myths on light, sunlight, sunscreen. It was crazy. And if you enjoyed this, go check out the full episode.

A lot in there. It's going to help you out. You don't want to miss it.