Security Now 1058: A Gift for the New Year

Summary

Security Now #1058: "A Gift for the New Year"

Hosts: Steve Gibson, Leo Laporte
Date: December 30, 2025

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Episode Overview

This special New Year's Eve edition of Security Now departs from the usual cybersecurity fare to revisit and update a landmark episode from 2009. Steve Gibson revisits his deep research into vitamin D, the science behind it, its impact on health, and new findings he's learned since the original show. The episode covers why supplementation may be necessary, how our environment and aging affect vitamin D, and practical guidance for listeners. The discussion is candid, scientific, and caring—a true "gift for the new year" oriented toward personal health and longevity.

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Key Discussion Points & Insights

1. Why Revisit Vitamin D? (00:47–01:35, 12:49–15:01)

• Steve & Leo acknowledge the lack of tech news during the holidays and decide to repeat a personal health-focused episode from 2009, now with updates.
• Steve: “Something has really come onto my radar that I almost feel I have an obligation just to share once…our listeners are important to me.” (12:54)

2. Vitamin D Basics: Production, Deficiency, Misconceptions (02:27–08:54, 21:38–26:00)

• Discusses why natural diet alone may not be enough due to food processing and drastically changed lifestyles.
• The body synthesizes vitamin D via UVB from sunlight—not from most foods.
• Vitamin D is not truly a vitamin, but a steroid hormone, essential for calcium metabolism and many other functions.
• Quote (Steve): “It is the most powerful steroid hormone in the human body...almost no dietary sources...we cannot get D from our diet.” (23:13)
• Historical context: rickets due to deficiency, cod liver oil as an early supplement.

3. The Science & Evolutionary Biology of Vitamin D (26:00–34:05)

• Human evolution: skin pigmentation adapted for sun exposure and vitamin D synthesis.
• Modern life indoors behind glass or with sunscreen reduces sun-driven D production.
• Vitamin D production in skin decreases with age—by age 65, only about 25% of youthful capacity remains.

4. Emerging Research & Epidemiological Data (34:05–47:24)

• Explores studies linking adequate vitamin D to dramatically lowered rates of colon cancer, digestive cancers, and total cancer mortality (by as much as 45% in some studies).
• Quote (Steve): “Individuals whose 25 hydroxy vitamin D levels were greater than 20 nanograms per milliliter had 1/3 the risk of colon cancer.” (34:05)
• Vitamin D’s role in mood (e.g., seasonal affective disorder), immunity (flu outbreaks in hospitals), and theories around latitude, vitamin D, and autism.

5. The Modern "Deficiency Crisis" (47:24–54:39)

• Reasons for widespread deficiency include less sun exposure, indoor living, and aging.
• Government-mandated fortification (milk) is not enough—most people would need to drink impractical amounts for sufficiency.
• "We have an unrecognized epidemic among both children and adults in the United States." (34:05)
• Recommendations for supplement use have changed; routine blood testing for D is now common.

6. How Much Vitamin D Do You Need? Testing & Supplementation (54:39–76:41)

• Old RDA (400 IU) based on rickets prevention is outdated; half an hour sunlight can make 10,000 IU.
• Supplementation is safe within reason; Steve describes self-testing and suggests aiming for lab values between 50–70 ng/ml.
• Quote: “Taking vitamin D infrequently like that [one 5,000 IU pill every three days] works because it has on the order of about a three or four week half life in our body.” (67:38)
• Cheap, effective supplements: recommends D3 (cholecalciferol) over D2.

7. Caveats and Medical Advice (09:42–10:22, 74:03–80:11)

• Not medical advice! Listeners should check with their physicians, especially if on medications like blood thinners.
• Possible toxicity with very high, excessive supplementation; responsible dosing and periodic blood testing is best.
• Quote (Steve): “We're not doctors. Consult your physician…But my point is that you can take a large dose and then let it be acquired by your system and then used over time as your blood level drops.” (76:41)

8. Dietary Sources & Other Supplement Notes (80:11–81:24)

• Food sources (salmon, oily fish) provide only limited D; cod liver oil also contains vitamin A, which in excess may counteract D’s benefits.
• Vegans/vegetarians: D2 from plant sources less effective; D3 typically from animal sources, but research ongoing.

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Notable Quotes & Memorable Moments

• On why this matters:
  “I'm literally willing to do anything it takes every single day so that I'm able to jump around more or less as I am now as I continue aging…you want to maximize the area under that [health] curve.” —Steve Gibson (15:08)

• On vitamin D as a hormone, not a vitamin:
  “It is such a shame that it's been lumped in with the vitamins because it is a steroid hormone. Really.” —Steve Gibson (23:13)

• On evidence from research:
  “An increment of 25 nanomoles per liter in predicted vitamin D level was associated with a 17% reduction in total cancer incidence…a 45% reduction in digestive system cancer mortality.” —Steve Gibson (34:05)

• On testing and personal experience:
  “My first test showed me at 23.6 nanograms per milliliter…after a week of sun, completely exposed…dropped to 21.3…I’m unable to produce vitamin D through being out in the sun.” —Steve Gibson (54:39)

• On realistic supplementation:
  "My favorite supplier is a company called Now Foods...120 [5,000 IU] pills costs $8.80. If you take one every three days, that's a year's supply for $8.80.” —Steve Gibson (67:38)

• On practical advice:
  “The really responsible thing to do is to get a test…as long as you follow the label, you cannot be toxic.” —Steve Gibson (75:35)

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Updated Recommendations & Practical Takeaways

• Blood Testing: Vitamin D status is now a routine blood test; ask your doctor.
• Supplementation: Steve now strongly recommends vitamin D3 plus K2 for most adults, especially those not frequently in the sun.
• K2 Addition: New research suggests K2 helps direct calcium appropriately when supplementing D.
  • “K2 carboxylates two proteins, which have the effect of driving the calcium into your bones, which is where you want it to go and keeping it out of your arteries.” (06:07)
• Risks: For those on prescription blood thinners (like warfarin), consult a physician before starting K2 (09:53).
• Target Levels: Aim for 50-70 ng/ml blood levels (as per Steve’s reading).
• Forms: Prefer D3 (cholecalciferol) over D2 (ergocalciferol).
• Annual Reassessment: Regular vitamin D testing recommended to tailor supplementation.

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Timestamps for Notable Segments

• How Steve got interested & history of prior episode: 01:12–02:27
• Sunlight, diet, and D production basics: 02:43–04:00
• K2 update & calcium handling: 04:42–06:09
• Anecdotes on D & immune health (including COVID/flu): 06:56–08:26, 07:37
• Vitamin D isn't really a vitamin: 21:38–23:13
• Cancer studies, risk reduction stats: 34:05–34:07
• Deficiency epidemic & why food fortification fails: 47:24–54:39, 74:03–75:14
• How/why sun exposure often isn’t enough: 59:39–67:38
• Supplements: brands, dosing, forms: 67:38–75:12
• Practical advice/testing your levels: 75:35–76:41
• Dietary sources & more Q&A: 80:11–81:27
• Final thoughts / GRC.com vitamin D page: 84:09–84:40

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Tone & Style

The episode is research-driven but highly conversational, with Steve sharing deep-dive science in a clear, methodical way. Leo provides lively, relatable commentary and prompts practical takeaways. The hosts repeatedly stress this is not medical advice, and listeners should consult their doctors.

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Where to Learn More

• Steve’s Updated Vitamin D Page: GRC.com → Research → Health → Vitamin D
  • Includes references, dosing, supplement recommendations, and medical literature.
• Get Tested: Ask your doctor for a 25-hydroxy vitamin D blood test.

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Summary

• Vitamin D is vital to immune function, cancer resistance, mood, and more; modern lifestyles and aging reduce natural levels.
• Supplementing with vitamin D3 (with K2) is safe, inexpensive, and powerful, but dosage should be guided by regular testing.
• “If I had to choose one single supplement… I think it would be vitamin D because of its powerful immune support.” —Steve Gibson (85:08)

For the full research and recommendations, see Steve’s page at GRC.com. Happy New Year and good health from Security Now!

Transcript

[Steve Gibson]

Podcasts you love from people you trust. This is Twit.

[Leo Laporte]

This is Security now with Steve Gibson. Episode 1058 For December 30, 2025, a gift for the new year. It's time for Security now, the New Year's Eve Edition. Hello, I'm Leo Laporte. Say hello to Mr. Steve Gib of GRC.com and the host of Security Now. Happy New Year, Steve.

[Guest or Co-host]

Happy. I can't believe 2025 is gone and we're launching into 2026, ready or not.

[Steve Gibson]

Wow.

[Leo Laporte]

Now, we figured there probably wasn't a lot of security news at the end of the year. Certainly if there was, we covered it last week. So we thought we'd do something special for our New Year's Eve edition.

[Guest or Co-host]

And we might be recovering from eggnog.

[Steve Gibson]

So, you know.

[Leo Laporte]

Is there any vitamin D in eggnog? That's the real question.

[Guest or Co-host]

No.

[Leo Laporte]

Way back when in the day. This goes back to the cottage days, 2009, when we weren't even doing video. Steve surprised me with a Security now that was devoted not to cybersecurity, now to personal security, to supplements. How did you get into this whole thing?

[Guest or Co-host]

So shortly after Spinrite 5 was finished and published, I, it was doing well and I had a lot of time on my hands. I had, I had scaled the company down to just sue and Greg and me. And I like, well, okay, now what? And I, it was before I was 50, I was in my late 40s, and I, oh, a young man.

[Steve Gibson]

Ah, yeah, those were the days.

[Guest or Co-host]

And I remember thinking, okay, when am I going to get serious about focusing on my health? And, and, you know, as a scientist, as a sort of health, curious person, I thought, okay, I'm going to start, I'm going to study supplementation, you know, adding stuff to my diet because it makes sense.

[Leo Laporte]

And isn't our diet, existing diet sufficient? No, that's kind of a softball question. Yeah, but that's what they always say. Oh, if you just eat properly, you don't have to have supplementations.

[Guest or Co-host]

The problem is we massively process food. We're now indoors behind glass. I mean, we've made a huge number of changes to the way we operate. We don't get the exercise that we used to. We're not spending most of our day out gathering food or hunting and exercising. So we've changed our environment dramatically. And this, of course, it does map onto vitamin D, because the way our bodies, as we're about to learn, anyone who doesn't already know, and it's a useful Refresher. Even if you kind of do that, like moms used to say, get outside, get in the sun. You need to get some sun. Well, it turns out there was a lot more to it than us just getting out of her hair. It was good for us, you know, as we will learn, UVB radiation, when it hits the cholesterol in our skin is what creates vitamin D. It's an amazing thing, actually. Yes. And there aren't many good dietary sources, you know, I mean, and in fact.

[Leo Laporte]

That'S why they started putting it in milk because.

[Steve Gibson]

Exactly. Yeah, exactly.

[Guest or Co-host]

Milk is vitamin D fortified because our government said, oh, you need some. Unfortunately, they had no idea how much the whole RDA system is based on. You will die if you don't get this much.

[Leo Laporte]

Minimum daily requirement. Yeah.

[Steve Gibson]

Yes.

[Guest or Co-host]

It is not the healthy daily requirement, which is one of the things that has steered so many people wrong. I think it used to be 400iu a day. I know that.

[Steve Gibson]

I'll talk about this in the podcast.

[Leo Laporte]

Yeah, I don't want to. I don't want to steal your thunder because we're going to talk about this. Want to talk about before we get into it, is in the intervening 16 years since you've done this, is there anything new to report?

[Steve Gibson]

Yes.

[Guest or Co-host]

What I did not talk about at the time, because it wasn't appreciated, was that it's very good to also add some vitamin K2 in addition to D3.

[Steve Gibson]

We'll be talking a lot about D2.

[Guest or Co-host]

And D3 here in a minute. I didn't talk about K. And I've updated the vitamin D page on grc. You can't go see it right now.

[Steve Gibson]

Because it's in front of me, Leo.

[Guest or Co-host]

And I haven't put it online yet, but it will be. It'll be online by the time people are hearing this. To talk about the need to add some K. What happens is that raising your blood level of D also causes calcium and phosphorus to be more strongly absorbed from your diet. That increases the calcium in your blood. And you don't want loose calcium floating around. It can get up to some mischief like plating out onto your arterial walls and clogging up your kidneys. So adding some K2, K2 carboxylates, two proteins, which have the effect of driving the calcium into your bones, which is where you want it to go and keeping it out of your arteries.

[Steve Gibson]

So I.

[Guest or Co-host]

On the updated vitamin D page, I show three different strengths of a supplement that I am now taking and have been for some time. So I'm Glad to be able to have this opportunity, Leo, to update. People who have been following along know about vitamin D, but probably need to add some K in order to sort of balance the effects of a really strong D presence. And we should also mention that in these intervening 16 years, one of the things that happened. First of all, there has been a lot of follow on research. Research has been kind of scarce because vitamin D doesn't cost anything and research does.

[Leo Laporte]

Nobody makes any money on it.

[Steve Gibson]

Yeah, yeah.

[Guest or Co-host]

But one of the things that we saw, aside from many of our listeners who did follow the advice in the original podcast and added some vitamin D to their diet, who then, after going through the winter, reported that wow, for the first time, like in their memory, they didn't come down with the common cold or sniffles or if they exposed their whole family to more D, nobody got sick. So that was just anecdotally interesting. But the other thing that we learned is that Covid status.

[Steve Gibson]

It'S always necessary.

[Guest or Co-host]

To remind people that correlation is not causation. So we don't know that it was vitamin D that that created far better outcomes for those who got Covid than those who were on had low vitamin D status. It could be that people who took vitamin D also, you know, tended to stand on their head more often and that that was actually the reason that.

[Steve Gibson]

Covid, Covid was, was better.

[Guest or Co-host]

We don't know.

[Steve Gibson]

But I believe, because we also know.

[Guest or Co-host]

That that vitamin D is a very strong immune support vitamin, which actually is not a vitamin.

[Steve Gibson]

I explained all this in the podcast that it's actually a hormone.

[Guest or Co-host]

It was completely misunderstood in the beginning.

[Steve Gibson]

But we still call it vitamin D even though it's not.

[Guest or Co-host]

Anyway, we saw some real effect during COVID of, of vitamin D status. Those who had high vitamin D status had much better Covid outcomes. So anyway, vitamin D3K2. Check out the vitamin D page at GRC, which I've updated with some recommendations for which supplements to take. And with that, Leo, let's go for a blast from the past.

[Leo Laporte]

A blast from the past. GRC.com for the vitamin D page. Go to Research Health. You'll see vitamin D. It will be updated after the show. Ladies and gentlemen, I think this is a very appropriate way for us to spend the New Year's Eve. You might be having a little something later in the evening, enjoying yourself a little bit. Maybe you did last night. Let's listen. And I did want to mention you hear a lot of ads for vitamins on a lot of other people's podcasts. This is not an ad. But I should also mention we are not doctors. And so you should always check with your health professional, your medical professional, before embarking on any health regimen, including this. But I think most doctors will encourage you to do this.

[Guest or Co-host]

Yes. And a good example is that I mentioned K2.

[Steve Gibson]

The K vitamins are blood thinners and.

[Guest or Co-host]

I'm sorry, no, they are the reverse.

[Steve Gibson]

They are blood clotters.

[Guest or Co-host]

So if you are on a blood thinner, a prescription blood thinner.

[Leo Laporte]

Yeah, warfarin.

[Guest or Co-host]

Exactly.

[Steve Gibson]

And that's the example I give on.

[Guest or Co-host]

This updated page because I do caution people that if you're, if you're taking subscript prescription blood thinners, check with a physician before you send a note to.

[Leo Laporte]

Your doc saying, I'm thinking of 5000 IU vitamin D and I'm thinking of taking K2. Is that okay with my existing medications and so forth.

[Guest or Co-host]

Speaking of which, that's the other thing that has changed. I remember asking my physician, I know back then, for a vitamin D test when I did my just my annual.

[Steve Gibson]

Blood test, and he said, what? Why do you want that?

[Guest or Co-host]

Why would you care now? It's routine.

[Leo Laporte]

It's true. It's true.

[Steve Gibson]

The world has, you know, caught up with this. So.

[Leo Laporte]

We're not doctors. Consult your physician. This is not an ad. We don't have an advertiser selling vitamin D, not like those other podcasts. This is a man who is brilliant, an autodidact who loves researching deeply into a variety of fields. And this is the result of his research back in.

[Steve Gibson]

Despite my current appearance.

[Leo Laporte]

Yes, people are wondering about your green hair, by the way, generally. We'll talk about that. Yeah. Without further ado, let's take a time travel trip back to 2009 and we'll see no video. This was audio only, but Anthony has prepared a lovely video kind of geek Yule log for you. So if you're watching it on YouTube, you can see that. And Steve, we'll reconvene after with some final thoughts and well wishes. Thank you, Steve Gibson. And now back in time. Hey, don't let me interrupt. I know we're having a blast here reliving 2025, but I thought this would be a good time to mention something we do every year around this time that's very important to us and to our ad sales. It's our twit survey. We do it because we don't really. And no podcast does know anything about you. That's, I think, a good thing. We respect your privacy, but we also would like to know a little bit about you to the degree you're willing to help us out. Just some basic information that helps us go to advertisers and say things like, well, 80% of our audience, is it, decision makers, that kind of thing. That's why we do. This annual survey should only take a few minutes of your time, as I said, is one of the ways you can contribute to keeping Twit on the air. If you would like to, before too long in the next couple of weeks, do it now while you're watching, go to TWiT TV Survey 26. It's our annual 2026 TWiT listener and viewer survey. It's very important to us, and I thank you. I really appreciate. And of course, if you don't want to do it or there's questions you don't want to answer, that's fine, too. But anyway, you can help us out. We appreciate it. All right, now back to the show.

[Steve Gibson]

This is the first episode. This is number 209, the first episode of year five. And we're gonna do something. We're gonna do something different this week and only this week. I don't want to worry and freak out our listeners, but something has really come onto my radar that I almost feel I have an obligation just to share once. You know, I mean, I'm taking action on it with myself, my friends, my family, everyone who's important to me. And so our listeners are important to me. And I want to, if nothing else, sort of plant a seed that may take root that it may be a couple years from now when they hear something else. It's like, oh, now I know that's important. Whereas, you know, they might tend to think, well, Gibson's not a doctor, so what does he know about this? And I'm not. I'm just a sort of a health hobbyist, as we all should be, since.

[Leo Laporte]

It is our health.

[Steve Gibson]

Well, yes, exactly. I stumbled on something which is, I think, very important. I will. I'm, you know, going to be. I'm not going to go overboard about it, but I want to just spend this podcast sort of, so that I've said my piece and I'm going to. I mean, I've done two months worth of research every day on the issue, and I want to explain what's going.

[Guest or Co-host]

On.

[Steve Gibson]

Run through some of the studies which have been done. I've put together a page on GRC which covers this topic, so that everything that I'm talking about I've got links to so people can follow up and do additional research if they're so motivated. If not, I completely understand. There's a whole spectrum of people from people who, you know, just think, oh, well, whatever happens, happens to people who are real interventionists and, you know, taking, you know, hundreds of supplements a day, you know, and everything in between. So what I can promise is, as always, a podcast, which is really, I believe, will be thought provoking and interesting for anybody who has a body.

[Leo Laporte]

Wow. All right, Steve, why, why, why are you so tan? What's going on?

[Steve Gibson]

Well, okay, to give a little bit of background here, everyone who's been listening to this podcast for years knows that I focus on code writing and computers and technology. A hobby of mine, which I've become increasingly focused on as I've been aging, is health. And in fact, really, Leo, it began when I was flying up to visit you in Toronto and appear on Canadian TV with Rogers Cable. I'd be at the airport and seeing people who were really, I mean, older than I, but, you know, not lots older than I who were having trouble moving around. You know, they were already, you know, like being really careful standing up and sitting down and moving slowly. And I thought, okay, you know, I'm. I think at that point I was probably 50 or maybe my very late 40s, and today I'm 54. And I remember just, just deciding, making a promise with myself that I am not going to be that person when I'm that age. I mean, I, I'm. And I'm literally, literally willing to do anything it takes every single day so that I'm able to jump around more or less as I am now, as I continue aging. And my focus is not on trying to live as long as I possibly can. I'm really not very focused on that at all. I don't care how long I live. I mean, more is better. But if you think of a chart that shows your quality of life over time, so that the horizontal axis is your life running from birth to death, and the vertical axis is how you feel your physical well being. You can imagine somebody who just, I don't know, who smokes their whole life, who abuses alcohol and drugs, doesn't take care of themselves. You know, they might have a relatively, you know, like, for example, a straight line decline from birth to death where they just, you know, they don't age well and they're not having a great time toward the end of their life. My goal would be to keep the slope of that line as horizontal as possible. That is, keep the, you know, keep health up as High as I can for as long as I can, and then to have it just drop off a cliff, you know, kill me in a week when it's finally time. But the point is that you want to, you know, from a math standpoint, you want to maximize the area under that curve. You want, you know, because that's the most health you can have for the length of time that you're alive. So my focus on health, which I've now had really, to a much greater degree since I turned 50, because it was like, okay, I've got the time. I virtualized grc. My employees are working at home. I'm able to work with a great deal of freedom. There's no excuse not to exercise, not to make sure I'm eating well, and not to do some research since I've got the Internet now. We all do. And it's just an amazing. It makes this information so much more available. So I subscribe to a number of newsletters, and I've been focused on various aspects of health. I pretty much knew about cardio years and years ago, and I've tried to keep myself in shape. And what happened about maybe about three months ago was just sort of bumped. On the radar screen were various mentions of vitamin D, which was not something I'd ever looked at or thought about. I was actually more aware of things like the B vitamins and their importance because, you know, modern food processing tends to kill off the B vitamins. They're fragile. So food is fortified basically to put back in what processing kills. And, you know, I knew about E and C, but somehow vitamin D had never. Something I had never really looked at very much. But I finally got to a point a couple months ago where it's like, okay, what's going on with this? And so I began to poke around and do some reading, and I thought, wait, whoa, wait a minute. This is seeming much more significant than I recognized and probably about four weeks ago. So about four weeks into this, I decided that, you know, this was something that I. That I really needed to understand. And I also, at some point figured I need to involve my family and friends and ultimately this podcast. So just for one week, I need to beg our listeners indulgence. I'm going to. I want to share what I have learned and see if, you know, for the sake of information, maybe it will resonate with some people. Maybe at some point in the future, when other information surfaces, they'll go, hey, wait a minute. I remember Steve talking about this. You know, he thought it was important these Other people think it's important, you know, maybe that will, you know, be enough to catalyze some thought so there's so much that's important about this. First of all, there's a real problem with it in that it's not a vitamin at all. Never was, never has been.

[Leo Laporte]

What is a vitamin? What is the definition of a vitamin?

[Steve Gibson]

By definition, a vitamin is something which is you do not make endogenously, that is, your body does not make it. It's something that you must acquire through nutrition from outside sources.

[Leo Laporte]

It's an amino acid too, right? Isn't that what it means, Vital amino acid? No, maybe not.

[Steve Gibson]

I don't know where the word comes from, but I do know that it's got to be a dietary source. Well, what happened was that it was discovered because of a chronic deficiency in an unknown substance. As we became more industrialized and people moved from rural settings into cities, and especially as children were employed in buildings, like in factories, they began getting rickets, which is a severe underdevelopment of skeletal bones. Now, what happened was that there was the discovery that cod liver oil cured this malady that children had. And so for generations, you know, parents, mothers would like, force their kids to have a tablespoon of cod liver oil.

[Leo Laporte]

I remember that from the Three Stooges, our gang. Yeah.

[Steve Gibson]

Nasty, oily tasting stuff. You really don't want it. But, you know, because it turns out that it's vitamin, this thing called vitamin D. And it's such a shame that it's been lumped in with the vitamins because it is a steroid hormone. Really. It, in fact, it is the most powerful steroid hormone in the human body. It is so powerful that when measured the units of measurement of the active form. And I'll explain what the metabolic process is in a second. But the metabolic form is measured in picograms per milliliter. That is, you know, we have grams, then we have milligrams is a thousandth, micrograms is a millionth, nanograms is a billionth, picograms is a trillionth. So it's on the order of 20 to 50 trillionths of a gram in our blood. I mean, amazingly little of this goes a long way, but it is found in almost no dietary sources. That is, we cannot get D from our diet. It turns out that that fatty fish is a source of D. But where it comes from, the way we get it is from the sun. And which is, which I think is really interesting because the, the first known application for vitamin D And really, the, the, the only place where it has received lots of attention is in our body's calcium metabolism. You know, it's generally felt that all life on earth came from the sea. First started in the oceans, evolved in the oceans, and then literally crawled out onto land and needed to adapt. Well. The ocean is a rich calcium bath. And so calcium is a fundamental component of the way we operate and our bodies. The human body manages and maintains the concentration of calcium to the best of its ability within relatively narrow margins. We need to have enough calcium from our diet, which is easy to get, but you have to have vitamin D in addition to calcium in order to build bone. D is inextricably linked to calcium metabolism. But for a long time, for hundreds of years, that's the only thing that we knew that it did. Well, looking back at sort of early humanity, we also know that we evolved in sub Saharan equatorial East Africa. That's where that's sort of the cradle of humankind. It is believed that when we were coming out of being apes covered with fur, that as we evolved be larger and have more muscle mass, we began to have a problem with cooling because we were generating. Our larger muscles were generating too much heat. So evaporative cooling wasn't. It was having a problem if we were covered with fur. So we literally lost our fur in favor of skin and more evaporative capability. The problem with that was that we were then being exposed to intense sunlight since our skin was no longer being protected by fur. So what started out as being lighter skinned, we ended up developing a much more rich melanin content. Melanin is the pigmentation in skin. And so we ended up literally becoming black in order to deal with the constant powerful equatorial sun in East Africa. And the blackness of our skin allowed us to tolerate the sun. But ever since the beginning, we were also using sun, that is the ultraviolet radiation, for fundamental chemical reactions which take place in our skin. A precursor of cholesterol called 7 dehydrocholesterol, or 7 DHC, that exists in our skin in abundance in youth. And we lose it as we get increasingly older. That 7 dehydrocholesterol is when it is zapped by an ultraviolet Photon, it converts that 7 dehydrocholesterol is converted into an early form of what, unfortunately, we have labeled vitamin D. It's not stable in that form, and so it shortly changes. It bonds around and just under thermal isomerization converts into something called cholecalciferol, which is the form of vitamin D that you can also get in a supplement that's transported to our liver, where our liver changes it through a process known as hydroxylation into the vitamin D which is measured in our bloodstream, something called 25 hydroxy vitamin D. And that's sort of the bulk storage form of this chemical. Our kidneys takes it the next step further hydroxylates it again and turns it into this super potent steroid hormone. Now that's involved directly. It's that hormone which is involved with the regulation of calcium metabolism and our bones. It turns out though, that many other organ systems in our body also have the ability to deal directly with vitamin D. And this is the information which is finally, due to the advancing of our medical science, finally becoming clear to people. When the holidays start to feel a bit repetitive, reach for a Sprite Winter Spiced Cranberry and put your twist on tradition. A bold cranberry and winter spice flavor fusion Sprite Winter Spice Cranberry is a refreshing way to shake things up this sipping season and only for a limited time. Sprite obey your thirst. I want to shift gears here for a second and run through a number of recent studies which have been done just to give people some sense for the pervasiveness of the influence of this. I'm holding a textbook, 450 pages, titled Vitamin D Physiology, Molecular Biology and Clinical Applications. I've read so many journal articles and studies that I'm becoming sort of well versed with the names of these people. And in fact, if I look at a book, a popular text on vitamin D, it's like, oh yeah, I know where that chart came from. I remember seeing that chart in the original source material. Wow. So this is chapter 13 where he's talking about non calcemic actions of 125 dehydroxy vitamin D3. Okay, that's the output from our liver, I'm sorry, the output from our kidney, the final stage, which is this powerful steroid hormone. And he says under historical perspective, when 125.2D was discovered, it was assumed that specific vitamin D receptors would be present in calcium regulating organs, including the intestine, bone and kidney. In 1979, Stumpf et al. And then he has a reference to the back of the chapter where he talks about that study reported on the localization of radiolabeled vitamin D in vitamin D deficient tissues and found that the radiolabeled vitamin D was localized in the nuclei of cells in the small intestine, kidney and bone, exactly as expected. But remarkably, they also found by audio radiographic analysis of frozen sections of tissues that this radio tagged vitamin D was also present in cells in the gonads, thymus, pituitary gland, pancreas, stomach, breast, teeth, placenta and skin. This observation was the impetus for the identification of the vitamin D receptors called VDRs. Then this is at the genetic level in all of these tissues, as well as in several tumor cell lines of leukemia, breast cancer, melanoma, squamous cell carcinoma, Colon cancer and prostate cancer. VDR activity was also detected in cells related to immunity, including circulating monocytes, activated T and B lymphocytes and macrophages, which is all part of our the way our immune system functions. So to give some sense for what is beginning to be understood, I've just jumped to chapter 22 under Epidemiology of cancer risk and vitamin D. It reads a nested case control study was conducted using subjects from the Johns Hopkins Operation Clue Cohort. This cohort consisted of 25,620 health adult residents of Washington. Yeah, it does.

[Leo Laporte]

As health adult, it should be healthy, obviously.

[Steve Gibson]

Yeah, yeah, healthy adult residents of Washington county, Maryland, who provided samples of serum, meaning their blood. Between 1974 and 1975, serum samples were thawed for all cases of colon cancer. So what happened is decades later, this study was done. So serum samples from back in 74, 75 were thawed for all cases of colon cancer and for two controls per case, meaning other people who did not have colon cancer and matched for age, race, sex, county of residence and date of serum collection. Sera, meaning plural of serum blood samples were analyzed blindly for 25 hydroxy vitamin D. Okay, that's that main circulating vitamin D, which is what's measured. That's the output of the liver before it goes into the kidney. That's sort of the storage form. Individuals whose 25 hydroxy vitamin D levels were greater than 20 nanograms per milliliter. And I'll talk about these numbers in a second. Get this. Greater than 20 nanograms per milliliter had 1/3 the risk of colon cancer compared with 1/3 the risk of colon cancer compared with those with lower concentrations. Okay, so there's one, a different study. This is from the American Journal of Clinical Nutrition, 2004, reads most to give some context, I'll sort of give a little more coming into this. Most humans depend on sun exposure to satisfy their requirements for vitamin D. Solar ultraviolet B photons, I.e. uVB, are absorbed by 7 dehydrocholesterol in the skin leading to its transformation to pre vitamin D3, which is rapidly converted to vitamin D3. Season, latitude, time of day, skin pigmentation, aging, sunscreen use and glass. That is the presence of glass between you and the sun since UVB is blocked by glass all influence the cutaneous production of vitamin D3. Once formed, vitamin D3 is metabolized in the liver to 25 hydroxy vitamin D and then in the kidney to its biologically active Form 125 Dihydroxy vitamin D. Vitamin D deficiency is an unrecognized epidemic among both children and adults in the United States. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risks of deadly cancers, cardiovascular disease, multiple sclerosis, rheumatoid arthritis and type 1 diabetes mellitus. Maintaining blood concentrations of 25 hydroxy vitamin D above 80 nanomoles per liter, which is in the literature. Sometimes they describe the concentration as nanomoles per liter but often also as nanograms per milliliter. The conversion is 2.5. So 80 nanomoles per liter is about 30 nanograms per milliliter. Says not only is the maintenance greater than that important for maximizing intestinal calcium absorption but also may be important for providing the extra renal 1 alpha hydroxylase that is present in most tissues to produce 125 dehydroxy vitamin D3. What he's saying there is that this is necessary for vitamin D to act directly on all these other tissues rather than being used for calcium regulation. Calcium homostasis Although chronic excessive exposure to sunlight increases the risk of non melanoma skin cancer, the avoidance of all direct sun exposure increases the risk of a vitamin D deficiency which can have serious consequences. Monitoring serum 25 hydroxy vitamin D concentrations yearly should help reveal vitamin D deficiencies. So that's sort of a bit of overview, but here's another. This is a this is titled Prospective study of predictors of Vitamin D Status and Cancer Incidence and Mortality in Men. And I'm going to skip the preamble and just. And I have all of this. I've got links to all of this on the page at GRC. It says from multivariate models an increment of 25 nanomoles per liter in predicted vitamin D level was associated with a 17% reduction in total cancer incidence. I got lost my track here. Oh incidence. And they go into the statistics. A 29% reduction in total cancer mortality with a relative risks of 0.71. That is if you had an increase in serum D levels and a 45% reduction in digestive system cancer mortality, 0.55. And then they summarize showing that the results were similar when they controlled further for body mass index and physical activity level. So basically saying that when all other influences were removed, vitamin D level in the blood had a direct bearing on cancer incidence. And there's like studies which describe similarly that higher levels of vitamin D are connected to lower levels of many different types of cancer. Pancreatic colon, rectal stomach, prostate, lung, breast, bladder, uterine, esophageal, kidney, multiple myeloma. I mean, it just goes on and on and on. There was one doctor who is at the ataScadero, he's an MD and psychiatrist at the Atascadero State Mental Hospital. John Cannell, because he knew that vitamin D positively influenced vitamin D mood. You know, we've all heard of seasonal affective disorder where people get kind of moody and gloomy in the winter, not surprisingly, when there's much less exposure to sunlight and when the sun is at a greater angle, not as often or as much overhead. It turns out that the atmosphere absorbs uvb. And so if the sun is not almost directly overhead, you're not getting much vitamin D. So he had his ward on vitamin D just for its psychological benefits. A flu went through the hospital that was bad enough that wards needed to be quarantined, he said. I've seen two interviews where he mentions how the ward to one side of him had such a flu outbreak that it was quarantined. The war did the other side of him and the ward across the hall as well as on the floor below. He knew that his patients had had social interactions with the inmates in the other wards and that the nurses were cross covering his ward and the other ward. So he figured that his people were similarly being exposed to this influenza. Not one single patient that he was treating in his ward came down with the flu, despite the fact that it was epidemic and to the level of quarantining. And now as a consequence, everyone at Atascadero receives vitamin D supplementation because of the strong evidence for its immunizational effect. So I mentioned to you when we were briefly talking about this last week, that there's even a theory now about where Caucasians came from, because it is believed that humans evolved in Africa with deep, dark, melanin rich skin which balanced the, the, the strength of the equatorial sun. It is now we understand that this hormone, which unfortunately has been mislabeled a vitamin to its, you know, I mean, which is, I think, largely responsible for a lot of people thinking, oh, well, you know, I probably get enough of this in my diet. I'm not going to worry about it. This, this hormone was, was, has always been generated by the sun's UVB interaction with our skin. And as we evolved, our population grew. We began to migrate away from equatorial Africa, north. What we now believe happened is that as we left the equator, the UVB radiation that we evolved under. I mean, literally just like oxygen, I mean, that important. You know, as I run through, I look at all these things that we are beginning to understand are relating to low levels of vitamin D. You might think, wait a minute, you know, how can, how can vitamin D fix that? Well, that's asking the question wrong. It's that we always had much higher levels of vitamin D in our blood than we do now. Because we evolved naked in the sun. I mean, and even now, here we are in industrialized mode. Basically living in dark UVB blackout caves called our homes and offices. Where no UVB radiation gets in. Where we're getting much less sunlight than we were even a couple hundred years ago when we were out farming and getting exposure to the sun. And of course, unfortunately, even more recently. There's been a great public relations campaign warning about the dangers of skin cancer. You must put on sunscreen when you go outside. So there's actually been many other things even recently which have begun to happen which confuse people. For example, autism has. It's been noted that it's on the rise. One theory is that, oh, well, we're just diagnosing it more. We're more aware of it. So we're more, you know, we're looking more closely. However, what they have found is that the incidence of autism directly correlates with the latitude of the mother of autistic children during pregnancy. The further away mothers are from the equator, the greater incidence of autism in their children.

[Leo Laporte]

Now, correlation doesn't equal causation.

[Steve Gibson]

No, that's a very good point. And that's something we have to keep in mind. My favorite example of that is that. Imagine that someone knew nothing about, you know, like an alien came down, knew nothing about, you know, the way we operate and was looking like. Was like watching the street, a random street in New York. And noticed that suddenly everyone put their umbrellas up and oh, look, then windshield wipers all began going on the cars. Well, if you didn't know any better, you didn't understand anything about what was really going on. You could say that raising umbrellas caused windshield wipers.

[Leo Laporte]

Right, right.

[Steve Gibson]

To go on. When in fact it's the other way around. It's completely different. That is related. And see, one of the problems with where we are and I mean we're beginning to understand the significance. The problem is that you cannot patent vitamin D. It is incredibly difficult to perform expensive studies.

[Leo Laporte]

There's no incentive to do that.

[Steve Gibson]

Yes, there is no financial incentive. There was a study that was done, so it's left to universities and research hospitals that have limited funding, especially now. There was a study between the years of 2000 and 2005 that took 1179 women in Nebraska, which I think I recall is at 41 degrees north latitude. This was a double blind, randomized, placebo controlled study. That's the gold standard of studies. It divided the women in half. It gave half of them a placebo and calcium and the other half 1100 IU per day of vitamin D and calcium. If you ignore. Oh, and these were all. These were in the year 2000 when this began. They were all, as far as anyone knew, cancer free. If you ignore and throw out the first year of any cancers that were found on the premise that those were already in the process of developing. During the rest of this study, the women who were taking the vitamin D plus calcium had 0.23% incidence of any type of cancer. 0.23.

[Leo Laporte]

I presume that's well below normal.

[Steve Gibson]

Compare. No, I mean compared to the other half of the women. So if the other half of the women were. You established their rate as 1.0. So it's less than 1/4 the number of incidents of cancer. So these studies exist. They're being published by Harvard and conducted by Harvard in the American Journal of Clinical Nutrition. I mean not flaky, strange publications that no one's heard of, you know, major fundamental research. But the problem is you can't patent vitamin D. Hey, Ryan Reynolds here wishing you a very happy half off holiday because right now Mint Mobile is offering you the gift of 50% off unlimited. To be clear, that's half the price, not half the service. Mint is still premium unlimited wireless for a great price. So that means of half day. Yeah, give it a [e-mail] Switch upfront payment of $45 for 3 month plan equivalent to 15 per month required new customer offer for first 3 months only. Speed slow after 35 gigabytes of networks busy. Taxes and fees extra. See mint mobile.com the other problem is that the rate of production of vitamin D as we age really falls off. Now I should mention something that I haven't said before and that is that just this morning I had my fourth weekly test. I didn't get in the mail, my third results, which would have indicated where I was after my second week. But what I did starting four weeks ago, I'm sorry, three weeks ago today literally was I had my A reference vitamin D level taken. I knew after all the research I was doing that I was going to be putting myself on vitamin D to a much greater level of vitamin D than is in my multivitamin. One of the problems with supplementation, and there is a problem with supplementation is that vitamin D can be toxic in very high doses. It is fat soluble, so it's not excreted from our body on an ongoing basis. So like any fat soluble vitamin, there's a concern that it will build up in your tissues over time. Nobody has ever become vitamin D toxic from sun exposure. But it has been determined that, for example, half an hour in the sun will generate about 10,000 IU, 10,000 international units worth of, of vitamin D which then over the course of a couple days enters your bloodstream. Well, I knew that I was going to be starting, I was going to be adding some substantial vitamin D to my daily regimen after all this research that I have done. But I had no idea what my current vitamin D level was and I wanted to play with generating it by the sun because once I started supplementing, once I added vitamin D to my diet, well, I would never stop. And there were, there were other things that I had added where I was thinking, gee, I wish I'd taken a measure beforehand so I could know what it was before. So I thought, well, let's sort of play with this. So I found out to my tremendous shock that I am, or well, am as far as I know, even now, substantially deficient. There's four levels of vitamin D terminology that the medical community uses. You have deficiency, then you have insufficiency, sufficiency and toxicity. So you obviously don't want to be toxic. You don't want too much. What you want is to be sufficient and really neither insufficient nor deficient. And I am deficient. I mean, really, I have a great diet. I eat lots of salads, I like fish, I sort of avoid meat. I'm not afraid of it. But you know, I'm doing everything I should. I have regular annual checkups. My cholesterol is where it should be. Blood pressure is where it should be a little higher than I would like it. But it turns out that adequate levels of vitamin D lowers blood pressure. In fact, it turns out that there is a seasonal sine wave cycle of blood pressure. The amplitude of the sine wave varies with latitude, and it is synchronized to the calendar. It is well known the blood pressure goes down in the summer and goes up in the winter. It is also, of course, we know that people tend to get colds in the winter and they get the flu in the winter. Why? Well, maybe, and we don't know this, but it's because our vitamin D stores are depleted. There was one study that attempted to demonstrate that watching too much television caused autism. That is, watching TV and autism were related. And it's interesting because it turns out that the people who did the study didn't actually interview people for how much television they watched. Instead, they used the rainfall figures in the area.

[Leo Laporte]

So they correlated to rainfall on TV watching.

[Steve Gibson]

And they said, well, we don't really know how much TV kids are watching, but raining, they're inside. What they were inadvertently doing was they were measuring probably the amount of sun that these kids were getting and that there. And that's where the correlation was. And in fact, they. When this was pointed out, they have revised their study in order to correct that. So the. The proper level of vitamin D is something which has. Is. Is still unknown. Believe it or not, the way the rda, the Recommended Daily Allowance, was established was that because we really didn't know. The one thing we did know was that a tablespoon of cod liver oil would prevent rickets. And since it had been given for so many generations, for so many years, and not caused a problem, they said, well, how much vitamin D is in cod liver oil? It turns out it's 400 IU. So that's what they said. Okay, we'll just say that that's the recommended daily allowance, 400iu. The problem is that being in the sun for half an hour supposedly generates 10,000 IU, so substantially more. And in fact, studies have been done of lifeguards and farmers in Puerto Rico that measure the actual level of vitamin D they have in their blood. And in this common term of nanograms per milliliter, they're in the order of 50 to 70. So the current clinically accepted range is 32 to 100. 100. I read the study and I've got a link to it on my page where the guy who did this, who set the 32 to 100, and you can Read all about how it was established. And he says, well, I just set 100 sort of arbitrarily because it's higher than we generally see in anybody who has a lot of constant sun exposure. We don't know that it shouldn't be higher or that any higher level is toxic. But, you know, it would seem that 100 is sort of a good place because, you know, that's all we know at this point. Anyway. My first test showed me at 23.6 nanograms per milliliter. And a week later, after a week of sun, where I'm spending half an hour in noonday sun, completely exposed, I mean, 100% baby, you know, the way I was born dropped to 21.3. I'm guessing that this is just, you know, it's just the tolerance of the lab test. I hoped by this time to have the results of the second week, which would be the third test. And a week from now I should have the results after the third week of the fourth. But for whatever reason, it doesn't look like I'm seeing any production. In the studies I've read, when you do get sufficient sunlight, your vitamin D level jumps up. It does take, you know, many weeks for it to reach whatever maximum it's going to. So it's sort of an exponential rise. But I would have certainly expected to see something after seven days of regular exposure. It looks to me like I'm unable to produce vitamin D through being out in the sun. It's disturbing to me that after five years with my internist, my doctor who was assigned to me, I mean, he was fast to give me a blood test, an immediate, a so called cbc, a complete blood count to look at all of the things that are, you know, typically considered. I know exactly what my HDL and LDL and triglycerides and, you know, all that stuff is he never checked my vitamin D. Now maybe if something were like really off, like my blood calcium was off, he would have said, well, let's check your vitamin c. That's what.

[Leo Laporte]

Dr. Maugham was saying is what about your serum ionized calcium?

[Steve Gibson]

Yeah, and that's where it should be interesting. Maybe that would have brought him to do it. But one of the. But you know, clearly I'm at a level now that is way lower based on, based on current thought. I would like to be to raise my 21 to something between 50 and 70 and somewhere, you know, like, like 60 being a goal. And you know, that's what I will likely begin doing.

[Leo Laporte]

And you Think that sunbathing is the key?

[Steve Gibson]

No, no, no.

[Guest or Co-host]

This was.

[Steve Gibson]

Remember, this was just an experiment. I only wanted.

[Leo Laporte]

Because there's other risks associated with that, of course.

[Steve Gibson]

Well, yes, there are. There are three types. Interestingly, there are three types of skin cancer. You have squamous cell carcinoma, basal cell carcinoma, and malignant melanoma. Malignant melanoma is the cancer that everyone worries about. Interestingly, though, it generally appears on areas of the skin that are covered by clothing, probably because statistically, most of us have more than the majority of our skin covered. The squamous cell carcinoma and basal cell carcinoma is the kind that we see on our hands, arms and face. It's also the kind that, you know that your dermatologist can freeze off easily. And it's not a big deal as long as you've got someone looking at your skin from time to time. You know, like your doctor takes a look at you to make sure that you don't have any of that. So the UV radiation definitely damages skin. It can be carcinogenic, and it does generate vitamin D. What is believed is that as we migrated away from the equator, because we are so dependent upon vitamin D, that it became a powerful natural selection factor in our evolution. And we know that our evolution took millions and millions of years. It looks like from the studies that we've done, that as we left the equator and populations moved north up into Europe, that we depigmented in something like several tens of thousands of years, maybe like 50,000 years, because suddenly the high melanin content we had, which was protecting us from the sun at the equator, was also now blocking our ability to produce vitamin D, which is a critical, I mean, an absolutely critical component, I believe, of human health. We know when it's really low that you develop chronic problems with calcium management and bones. Your body takes calcium from your bones to preferentially manage your blood calcium level, because that's even more important. So your bones represent essentially a calcium well or a calcium repository that if you don't have enough vitamin D and or calcium in your diet, there are mechanisms that'll pull calcium from your bones which you don't want. But now we're learning that there are. That it's very likely that this very powerful and necessary hormone has been incorporated into many other systems in our body. And I imagine that many of us listening to this podcast are in the same position I was. I mean, I'm not a sunbather. I'm not out in the sun. I Actually, you know, I mean, I get a little bit of sun, I'm not afraid of it, and I want to make sure I don't burn. But the problem is that again, we're in a information deficit because studying these things costs money. And you can't patent the sun, you can't patent sunlight.

[Leo Laporte]

There's an analog because we know that salt is very good for treating a lot of things like cold sores and so forth. But nobody's going to study that because salt is free and cheap and unpatenable.

[Steve Gibson]

But what's really interesting is there are vitamin D analogs which the pharmaceutical company are exploring. Sure, yeah, they're making little tiny to.

[Leo Laporte]

Make money on that.

[Steve Gibson]

Yeah, exactly. Because that they can patent. And in fact, there are now some effective psoriasis medications which are, which are all based on vitamin D analogs. So they tweak the molecule a little bit. There is a problem with high levels of vitamin D because as I mentioned, it is toxic in really high levels. But they want to use this, the, the, the very powerful, the125 dehydroxy vitamin D, which is what your kidney produces. They have found that it is extremely good at fighting cancer. The problem is if you gave someone enough of it to fight cancer, it would turn you into limestone. So, you know, that's not a good thing. So what they're trying to do is they're trying to find a variant of this vitamin D which will have the effects they want and mitigate the effects. They don't. If they can do that, then they can patent it and create a new drug. You know, I'm not adverse at all to using the medical system if I need to. I'd much rather stay healthy, not need, you know, major surgical intervention of any kind. And so, you know, vitamin D will be part of my regimen going forward. And you know, the, the takeaway I think would be to, for those listeners who have a doctor who are the kinds of people who know what their cholesterol is and so forth, next time you go say, hey, let's find out what my vitamin D level is. And I'm sure that if my doctor knew that I was 21, he'd say, oh, I mean, even the, even the blood test results shows the level 32 to 100 and shows me as, as, you know, extremely low. He would have said, oh, well, we probably need to put you on some vitamin D, give you some vitamin D supplementation and we'll retest in 90 days. There's no indication that it could hurt and my sense is it can only help.

[Leo Laporte]

So you're gonna start taking supplements?

[Steve Gibson]

Yes. In fact, today I did my last. I've done my three weeks in the sun. I don't have the results.

[Leo Laporte]

I still like getting the sun. I have Italian skin, so. And of course, I get checked every year for first for skin cancer. But I like getting some sun. I just. It feels.

[Steve Gibson]

Well, it turns out that it also releases. Being in the sun releases a shoot. It's a form of narcotic.

[Leo Laporte]

Yay. No wonder I feel so good.

[Steve Gibson]

You don't know. I mean, again, it's not surprising. I mean, we were meant to be in the sun. We evolved in the sun. I think more than anything else from a natural.

[Leo Laporte]

It does. It feels good. It feels like this is where I should be. Same thing with the ocean. I feel good when I'm at the ocean. I should be.

[Steve Gibson]

And, you know, I mean, we grew up with our parents saying, oh, go outside and get some sunshine.

[Leo Laporte]

Not anymore. Kids are slathered with sunscreen. They wear big bonnets. I mean, they don't get the sun anymore.

[Steve Gibson]

Yep. I mean, so there really has been a change. There are. There is study after study that demonstrates that. That cancer, autism, allergies, diabetes, an amazing number of maladies have latitudinal correlations. And they've even noticed, for example, that even at a high latitude, if you're at high altitude, then the incidences of these problems drop because you've got less atmosphere between you and the sun. And the other problem is you cannot get sun in the sun. That matters in the morning or in the afternoon. It's got to be when the sun is almost directly overhead.

[Leo Laporte]

Oh, that's interesting.

[Steve Gibson]

The reason is that there's this. There's this beautiful gap in atmospheric absorption right through what we, not surprisingly, call the visible spectrum. And we call it the visible spectrum because that's what we see. But you'll notice we don't see in the ultraviolet. I mean, the ultraviolet and the visible are like. They're the same range of radiation. We don't see in the ultraviolet because it's dark most of the time. In the ultraviolet, it's only briefly light for a few hours around noon. And then the sun's angle becomes Such that the UV radiation, the UVB, which is between 290 and about 320 nanometers, it's almost completely cut off. So evolution would never give us vision that is only useful for a couple hours during the day. Instead, we see in the visible spectrum where. Which is not Absorbed the way UVB is. And so we're able to for example, hunt by moonlight or see from the time the sun comes up to the time the sun sets, which is, you know, much more useful. It's. But at the same time that visible radiation doesn't have the energy and doesn't have the wavelength to interact with us chemically the way UVB does. So we need that uv, that UV radiation. And again I want to make sure that people understand I'm not suggesting, I'm not promoting spending time in the sun. It's. I was about to say that I've read some studies but again we're in a study deficit here that say that by the age of 50 our ability to produce vitamin D cutaneously endogenously in our skin has fallen by half. And that by the age of 65 it's down to 25% of what it was. So you cannot get the D you need through sunlight. And you did notice, maybe you weren't kidding that I'm a little tanner. I've been, you know, I was looking at how much sun I was getting and whether I was tanning. I'm after three weeks of half an hour a day I have tanned a bit, not too much. But the problem is tanning is a regulating mechanism. Tanning is the production of this melanin polymer which is 99.9% efficient at absorbing UVB. Melanin absorbs UVB and turns it harmlessly into heat. So it protects our skin from DNA damage. Unfortunately, it also protects it from generating vitamin D. So here's the problem. I'm clearly receiving enough sun because I'm adapting to it. My skin is darkening which is my body's attempt to down regulate the amount of UVB radiation that I receive. In the process, it's downregulating my ability to produce vitamin D. So my point is that as I get older and my. And what happens is we lose the cholesterol in our skin. You know how like your so called you get thin skin. You know, it is a loss of cholesterol in our skin which, which reduces our ability to produce vitamin D. Yet we're still going to be able to get tan. You don't lose your ability to tan. So what that says is that when you're no longer young and able to produce as much vitamin D as you did, no amount of sun can give it to you because your body is going to tan and down regulate, not only well down regulate all the UVB that gets into your skin. And to further Cut off D. So I think the only solution is to monitor your vitamin D levels and supplement. Now the good news is because it's not patented, because it's inexpensive to make. It's very inexpensive. One of my favorite suppliers is a company called Now Foods. And my favorite place for buying stuff is iherb.com they're great service, great delivery, very good prices. Now foods has a 5000iu vitamin D which their label recommends you take one every three days. Taking vitamin D infrequently like that works because it has on the order of about a three or four week half life in our body. It lasts a long time because it's fat soluble. So our liver takes it up and our fat tissues, all of our adipose tissues, dissolve the vitamin D. It's very easy to swallow because remember how concentrated it is. We're only talking about micrograms of D. It's made in huge vats of olive oil because it's fat soluble. So they use, they start with a huge vat of olive oil. You know, pour a carefully measured amount of vitamin D in, then dilute, you know, then dissolve that vitamin D and then they produce these little tiny gel caps. So 120 of those costs $8.80. Well, if you take one every three days, that's a year's supply of vitamin D. In a useful dose, that would be 1666 IU per day. The US government has said that even that 2000 IU per day is an absolutely safe dose. Many nutritionists feel that that's way too low. But you know, follow the label and then you're getting a useful amount of vitamin D for $8.80 for a year. Yeah, yeah, I am. I just, if I, you know, there's, I've looked at this stuff and if I had to take one thing, if I, if I were, I was, I was gonna say on a desert island, but even on a desert island, I don't think I can any longer make a sufficient amount of vitamin D by getting by, by being in the sun because I'm gonna tan and that's gonna cut off what I would have been able to make.

[Leo Laporte]

Is there a risk to supplementing the risk? Do you overdo it?

[Steve Gibson]

Yes, the risk is at the high end. And in fact, this is the conundrum is that our government has, our government does put D in stuff. It puts me in milk. And they aren't we getting.

[Leo Laporte]

Because we're all drinking Starbucks, getting a lot more milk than ever before.

[Steve Gibson]

Well, here's the problem is Milk has actually gone out of fashion, and we're not drinking the kind of milk we do. Believe it or not, rickets has made a comeback in the last few years.

[Leo Laporte]

Unbelievable.

[Steve Gibson]

Because children are not drinking milk. Parents, soda population. Exactly, exactly. And, you know, sugary fruit drinks. So the government puts. The government mandates that 400iu be put in a quart of milk. And the problem is you would have to drink about 10 quarts of milk a day in order to get a physiologically useful amount of vitamin D. But here's the problem. If the government. Because this is a powerful steroid hormone. If the government.

[Leo Laporte]

They can't put more in.

[Steve Gibson]

Yeah, exactly. If the government did raise the levels of D that were in our food supply, there's a wide variation in the amount of different types of food that different people eat. Maybe there is someone who drinks quarts of milk a day.

[Leo Laporte]

So they could be doing themselves harm if they had too much of it.

[Steve Gibson]

If there was too much of it.

[Leo Laporte]

If they were supplementing and they drank four quarts a day and they were getting out in the sun and on and on.

[Steve Gibson]

Yeah, I mean, I. I think that the only. I mean, the really responsible thing to do is to get a test that you could buy your own, as I have been doing. Oh, really?

[Leo Laporte]

Oh, these aren't with your doctor?

[Steve Gibson]

No.

[Leo Laporte]

Do you draw blood? How do you get.

[Steve Gibson]

Oh, yeah, I go to a lab every Wednesday morning to LabCorp. There's a group called Life Extension foundation, lef.org they offer retail blood testing services. So you pay them, they mail you the forms, and then you take that to a lab nearby. They take a vial of blood, and then about five days later. Normally this was late in this third test, but normally it takes five days and you get the results. And so. And it's. I think it's $67 for a non member, 47 for a member. So if you were gonna do several of these, I think membership is $75 a year, so you get a discount.

[Leo Laporte]

See, I know what people listening. What I'll do is I'm not gonna get tested. I'm just gonna go out and buy some vitamin D tabs. Is that a bad idea?

[Steve Gibson]

I don't think so. As long as you follow the label, you cannot be toxic. Because, for example, Walgreens will have a thousand iu and it'll probably say, take one or two a day, and, you know, and follow the label and you're fine. This 5,000 IU from Now Foods says take one every three days. Because, I mean, well, for example, because it has the half life it does. Some doctors will megadose their patients monthly, like give them 100,000 IU. But I'm not recommending that. You absolutely would only do that under a doctor's career. But my point is that you can take a large dose and then let it be acquired by your system and then used over time as your blood level drops. It's just easier for me, for example, to do one every three days or I will be monitoring my blood level. So I will probably take more because I'm wanting to find out what level I need to take in order to put my blood where it should be. So again, ask your doctor where, you know, for a vitamin D test, get one for yourself or think about, you know, getting some real D. I should mention that there are two types of D that you can purchase. There's D2, which is called ergocalcifetrol or D3, which is I can't. Cholecalcifetrol. D3 is what we make. Cholecalcifetrol is the only kind you really want to take. It is. It is essentially biologically identical to what we manufacture. There is some concern. For example, I think it's not kosher, believe it or not, because it's made from. It's made by irradiating the lanolin from lamb's wool. Ergo, calciferol is made from irradiating fungus. So it's 100% plant based. But it's vitamin D2. And some studies have said that it only raises your vitamin D levels about 25% as high as D3. So D3, which is what we make when sun hits our skin, is substantially more effective than D2. So I imagine what you would find, you know, for example, this. Now foods vitamin D is vitamin D3. Walgreens drugstores in their little health section. What you want to look for is the cholecalciferol. And you know, 1,000 milligrams per day is without question safe. The US government says that up to 2,000 is safe. Nutritionists believe safe dosages are far higher. I wouldn't go there unless, you know, you knew what your blood levels were. You want to make sure it is possible to be hypersensitive to vitamin D. There are some genetic conditions that could cause complications at much higher levels.

[Leo Laporte]

We should emphasize we're not physicians. You should check with your physician before you do anything and probably ask your physician what he thinks and get a D test. Are there natural food sources? I like to get this stuff from food. Can I eat a lot of broccoli or something?

[Steve Gibson]

No, that's just it, Leo. It is not in our food supply. It's interesting. The only way the Eskimos were able to keep their relatively high level of pigmentation is eating oily fish.

[Leo Laporte]

Right.

[Steve Gibson]

They have a diet high in fish and the fish is the only source. A 3 1/2 ounces of salmon has about, I think it's 380iu of vitamin D. And again, there are studies that have been done that estimate we use about 4,000 IU a day. I've seen the numbers like 3,800, 4,000, something like that. So again, you would need to be eating an awful lot of salmon. You know, 10, what, what, 35 ounces of salmon a day, which you might get tired of after a few days.

[Leo Laporte]

And it might not be good for you for other reasons.

[Steve Gibson]

Exactly. So also, it turns out that cod liver oil is really not the best source. It does give you vitamin D. It also contains another, the other fat soluble vitamin, vitamin A. And a lot of vitamin A can be a problem. And it also, vitamin A genetically looks very much like vitamin D. And there have been reports that say that A can block the positive effects of vitamin D. That is, other than on calcium metabolism where we know that it's effective. So getting A in the form of beta carotene is really what you want because your body is able to convert as much as it needs over to A. Anyway, you know, that's my readout on D. I think it's important it's not a vitamin. I think it's had a bad rap by being misnamed a vitamin by early, early medical science that didn't know what it was but just said, oh well, it's a nutritional thing because it's in cod liver oil. In fact, it's not anywhere else in our diet because we evolved in the sunlight, we need it. Otherwise all kinds of things stop not working as well as they should. And there was, in fact, it was funny. I was talking to some friends at Starbucks a week or two ago and one of the people said they'd just seen a news blurb saying that 70% of US children are vitamin D deficient. I mean, it is a problem, but the conundrum is because it is a powerful hormone, we can't put it in our food supply. We weren't meant to get it really in our food supply. There's barely enough now to prevent rickets and it's not even doing that anymore. Because people aren't, you know, they're staying away from dairy products more than they should. But if we put a lot more in, then there'd be, there'd be the possibility that, that people could reach toxic levels of it. So, I mean, it needs to be done. You know, young people in the sun is probably what you want to do. Although there's a concern about skin cancer, which is, is, is to some degree warranted. So I don't really see a way other than using supplements and doing it with care and wisely. I think it's important.

[Leo Laporte]

Steve Gibson, you know, this is a little bit of a departure for the show, but I think a fascinating topic and I could see why you were anxious to share it with us. Thank you.

[Steve Gibson]

Well, so I didn't, I didn't give the webpage. I'm in the process as I record this of I have a lot of it. All the pages are assembled here at home. I haven't yet put them up on the site, but It'll just be grc.com health.

[Leo Laporte]

All right.

[Steve Gibson]

And that will get anybody who wants to read this research. I've got, I've captured PDFs of all of this. They're all online. People can poke around, read this for themselves. And I hope maybe I've given, if nothing else, people something to think about.

[Leo Laporte]

Oh, I'm going to run out and get some vitamin D, I can tell you that right now. That's it. You know, I think that was kind of a landmark. It sure surprised me.

[Guest or Co-host]

I loved it. I remember you, actually, you prompted me saying, well, Steve, what security problems are we going to talk about this week?

[Steve Gibson]

And I said, well, we're going to do something a little different this week.

[Leo Laporte]

I'm glad you did because I've been taking vitamin D ever since and my health has been excellent.

[Guest or Co-host]

And I was motivated by what I learned. It was that, like, okay, this is, I mean, there's a bunch of other stuff I have take that, I do take that. You and I have talked about off the, off the record. I mean, so there's way more that I'm doing. But if I had to choose one single supplement that I would, if I could only take one thing, I think it would be vitamin D because of its powerful immune support.

[Leo Laporte]

We will be back next Tuesday, of course, January 7th with another edition of Security now in which we will talk about security. We do it every Tuesday right after Mac break weekly. That's 1:30 Pacific, 4:30 Eastern, 21:30 UTC. I hope you'll watch the show you can do it live. Of course as with all of our programming on Twitch and X.com, facebook, LinkedIn, Kick and of course if you're a Club Twit member, you get special behind the Velvet rope access in our Club Twit Discord. We chat in there as well of course download it after the fact, Twitter TV SN or subscribe in your favorite podcast player. Steve's website GRC.com has special versions of it 16 kilobit 64 kilobit. He also has got the Show Notes there. You can subscribe to the Show Notes there if you click the email link. And let's not forget Steve's bread and Butter is at GRC.com Spinrite, the world's best mass storage, maintenance recovery and performance enhancing utility and now is DNS benchmark pro for making sure you got the fastest Internet you can get in your house. All of that version two just came [e-mail] Steve have a wonderful New Year's. We'll see you 26.

[Steve Gibson]

Can't wait. Bye Security now.