So about 3 weeks or so ago, I listened to an episode of Underground Wellness Radio with Chris Kresser and a caller asked/informed about the possible side effects of synthetic vitamin D supplementation. So that got me thinking…
Now, I take Now Foods Vitamin D3 5000 IU capsules almost daily. And I’ve been doing that for well over a year or more. I haven’t seen any issues but, sometimes you can’t see them because you get used to them. Fair. I did a bunch of research when I first decided to take vitamin d3 and I had concluded it is probably safe and beneficial.
So I started taking them.
After I listened to that show I decided that I should try an experiment and stop taking the vitamin d3 and see what happens. So, at first nothing seemed different and that should be about what would happen since my body would have stores of vitamin d3 to tap into. I was just not replenishing it.
Work got a little stressful last week since I was juggling two projects that both needed to be done soon. And then my sleep suffered for some unknown reason. All in all, stress went up. I’ve certainly read in many places that vitamin d helps with stress. So now that I wasn’t taking any vitamin D and I am not in the sun much at all—I work with computers and I live in NYC, it’s Autumn now—I suspect my stress tolerance was lowered.
When my body doesn’t like something, my skin is first to complain. And complain it did. So that’s always a sign that something is wrong. Yesterday, my throat bothered me. I don’t know from what. I do know that vitamin D also protects from getting colds and things like that. At this point, my vitamin D levels are probably not optimal after weeks of no supplementation, no sun, and extra stress.
The real difference maker is that I didn’t notice any positive difference when I stopped taking vitamin D3. So, this morning I decided to do some more research and see where these studies where that showed vitamin D supplementation was possibly bad. I couldn’t find any conclusive studies. There was one in the ’30s that said it caused birth defects. I couldn’t find the study just someone talking about it and they were not specific about it being D2, D3, or some pharma grade version. Of course, vitamin D3 is given now to PREVENT birth defects so?
The Vitamin D Council points out that D2 is not natural to us so they do not recommend D2 or pharma prescribed versions. Fair enough. I knew that already. I was taking D3. I then did some more researching and remembered that the D3 we synthetically make is biochemically identical to what our bodies make. So if there’s a negative, it would be from the difference in how our body gets it. Eating vitamin D3 bypasses the body’s natural mechanisms to regulate the amount of D3 so there’s some danger of overdose there BUT, oral consumption of D3 isn’t foreign. Cod liver oil and other foods do contain D3 and we eat it.
So I thought about it. Thought about it. And then popped a 5000 IU capsule.
My conclusion is that it’s probably better to take it than to not take it at this point. Unless I’m out in the sun all day, this is the better alternative. I also feel a lot more chipper—might just be a placebo effect—today after taking, in total, 35,000 IU of it. haha! I’ve been off for weeks so I’m going to go for a big dose. Scaling back tomorrow and the day after, obviously.
So I did some MORE looking around and I really can’t find a single study that shows dangers of vitamin D supplementation. There’s a few that say D2 is not as good as D3 but whatever, I don’t think anyone really takes D2 over D3. Every vitamin D supplementation recommendation I’ve ever seen says to take D3.
The closest I got was this singular PDF from a medical doctor talking about the dangers of all kinds of synthetic supplements like Vitamin E, B, etc. The little snippet on D mostly talked about the dangers of overdosing—which in my crawl through scientific papers found that 10,000 IU/daily has 0 adverse affects so that’s a safe upper-limit, I’d stick to 5000 IU if you’re squeamish about it.
That PDF does state:
Vitamin D3, called cholecalciferol, is from animal sources, and is the active form, like the vitamin D obtained from sunlight.
and that there’s these pharma versions:
A variety of synthetic vitamin D compounds have been developed, the most common being calcitriol, doxercalciferol and calcipotriene.
The Vitamin D Council notes that calcitriol in high doses has been shown to cause hypercalcemia. They also don’t consider D2 or D3 synthetic like calcitriol and friends.
All other random web sites spouting about the dangers of vitamin D supplementation didn’t look credible. One was really just trying to push you to buy their line of products so there has to be skepticism there.