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Should You Supplement With Vitamin D?

My opinion? Just don’t “D”o it…

This may be an unpopular opinion. Watch the video to find out why I DO NOT recommend taking Vitamin D supplements, and a better way to get your Vitamin D instead.

Video Transcript

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It’s summertime and everybody’s starting to get outside, and I’m getting questions like, “Should I take my vitamin D supplements?”

My answer is: no, don’t do it.

I’m not your doctor, but here are some of my thoughts and theories on vitamin D supplementation.

I don’t think the vast majority of people need to be taking super-physiologic doses of vitamin D. I don’t think most people need to be taking vitamin D supplementation at all. I think there’s a less expensive way and probably a better way to get your vitamin D needs taken care of than taking copious amounts of vitamin D supplements, which I think could potentially be problematic.

So where should we get most of our vitamin D?

We are designed so that 80 to 90% of our vitamin D should be generated from the sun.

We convert a form of cholesterol in the skin via UVB lights into vitamin D, and then that vitamin D can go to the liver and it can be converted into what we call 25-OHD, which is the circulating storage form. And then it can be converted into 1,25-vitamin D, which is the activated form.

Vitamin D can also go into fat cells and get stored, and there’s a whole long reason for this to occur, which I’ll do on a podcast coming up.

But if we’re designed so that 90% of our vitamin D should come from the sun, then why are we taking lots and lots of supplements?

And why would I say that 80 to 90% should be coming from sun exposure?

Well, one, the scientific literature says that. And two, the other thing is there is very little vitamin D in food. There’s very little, and the food that has the greatest amount of vitamin D, which still is not a lot, is cold water fish. So that’s where most of the vitamin D is.

So if nature never really had high levels of vitamin D in it, maybe that’s because we didn’t need to be getting the vitamin D from our food and we were getting vitamin D from another source, which is the sun.

So I know before you jump to say, Hey, my food has a lot of vitamin D in it, very little non-fortified food contains actual vitamin D. It’s primarily the cold water fish that have any significant level of vitamin D in it.

So if there’s very little in food, then it probably makes sense that we shouldn’t be supplementing our diet with lots of vitamin D or with high vitamin D-fortified foods. We should be getting outside and getting sun exposure to then generate our vitamin D for the body.

So you can get vitamin D two ways: sun or food supply.

And so once that we either make the vitamin D from our skin or we take it from supplementation, or we get it from our food, it’s got two places it can go….

It can go to the liver, and in the liver, it can be converted into the circulating storage form called 25-OHD, or it can go directly into adipose tissue and be stored there. And some people think it just gets stored there, but other literature shows that vitamin D needs to go there for a lot of people for a significant amount of reasons.

One of the reasons Vitamin D gets stored in adipose tissue is to calm the immune-inflammatory process. The second is to make more room for excess calorie storage. (We’ll talk about that on a future podcast episode.)

But then once 25-vitamin D is in circulation, then it can be activated or converted to 1,25-vitamin D. It was thought for a long time that this is just done in the kidneys so that when calcium levels drop, there’s a hormone called parathyroid hormone that goes to the kidneys and signals the kidneys to convert 25-vitamin D to 1,25-vitamin D, and that was the primary source.

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But we now know that there are a lot of other cells, tissues, and immune cells that can generate 1,25-vitamin D.

Why is that important? Because 1,25-vitamin D is what actually does the work.

When 1,25-vitamin D binds to something called the “BDR Receptor,” that’s what triggers all these benefits that we associate with Vitamin D.

I’m not standing here saying you shouldn’t have sufficient levels of vitamin D. I think you should have sufficient levels of vitamin D. I just don’t think we should be taking it like a drug, a thousand, 2000, 10,000 IUs per day on a consistent basis.

If we’re doing that, to me that means we don’t understand where is the vitamin D going. And one of the things that’s really important is that when you have elevated levels of 1,25-vitamin D, it actually inhibits the liver’s conversion of vitamin D to 25-vitamin D.

So if you have chronically low 25-OHD Vitamin D levels, you should be thinking one of two things...

One, especially if you’re getting sun exposure and you’re taking copious amounts of vitamin D, you should be asking “Where is the vitamin D that I’m taking? Am I not absorbing it? Is it going out in my stool?” And if that’s the case, there’s probably GI issues, there’s bile issues, there’s fat malabsorption issues.

Two, is it coming into the body and going right into fat cells and being stored there? Or is it being converted? Is it not able to be converted to 1,25-vitamin D because maybe I have a magnesium deficiency? Or is it being converted almost as quickly as it’s being generated into 1,25-vitamin D to do the work it’s supposed to do? And because you have this high conversion of 25 to 1,25-vitamin D, you’re getting this kind of feedback mechanism that says, “Hey, we’ve got enough 1,25-vitamin D, stop making 25-vitamin D. We don’t need more.”

And in that case, more of that vitamin D that’s coming from sun exposure or from your food or supplements is going to be driven into the adipose tissue, and there are big problems that can occur potentially as a result of that.

So what are you getting measured?

Typically, when you’re getting a lab test done, you’re not getting 1,25-vitamin D done. That’s rarely ever measured. You’re not getting vitamin D measured. You’re getting this intermediate step done, 25-OHD, and we think that gives this really clear picture of what’s going on and it doesn’t.

So when we’re getting our vitamin D levels tested, you’re not testing vitamin D, you’re not testing what is stored in the adipose tissue. You’re not testing the active form of vitamin D (1,25-vitamin D), you’re not testing free vitamin D, which is a whole nother discussion, and you’re not testing the deactivated form of vitamin D to find out if this 25-vitamin D just got deactivated and never even made it to the 1-25. So it doesn’t give us a clear picture of what’s going on.

When you look at lab ranges, in most places you’ll see that it should be greater than 30 nanograms per deciliter. But in the functional medicine world, you’ll hear people saying, “Hey, we’ve got to drive it up to above 50, to 60 to seven to 80.” I think that’s ridiculous.

Estimates are that you need about 600-800 IUs per day, and yet we have people taking 2000, 4,000, 10,000 IUs of vitamin D per day because they’re trying to figure out how to get their 25 vitamin D levels up.

If you’re taking more than 1,000 IUs per day, then there’s something going on with your chemistry that either you’re not absorbing it or it’s getting pushed right into the adipose tissue. If it’s getting pushed into adipose tissue and you’re gaining weight, that vitamin D might be actually contributing to your weight gain.

There are lots of studies out there that say Vitamin D is great, but when you look at some of these studies, there isn’t actually a great body of literature that consistently shows that vitamin D is helpful for all situations and that there are some potential downsides and risks.

Some possible problems [with too much Vitamin D supplementation] are immune dysregulation, decreased absorption of vitamin A, increased absorption of heavy metals…

In functional medicine everybody’s worried about, “Oh, heavy metals, you’re overloaded with heavy metals.” Well, how do we get them? Maybe the copious amounts of vitamin D supplementation people are taking.

Instead of taking vitamin D supplements, how about just getting outside for 10 to 15 minutes per day? Make sure your arms and maybe your face are uncovered, and you’ll generate about 1,000 IUs of vitamin D!

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Hi, I’m Dr. Eric Balcavage, owner and founder of Rejuvagen. If you’re struggling with health issues or have questions, let’s chat. You can schedule a 15-minute call with me to get started.