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Your own link shows that what is considered toxic levels are far higher than most people would expect. Vitamin D toxicity is not that easy to accidentally hit.

Overdose has been observed at 1,925 μg/d (77,000 IU per day). Acute overdose requires between 15,000 μg/d (600,000 IU per day) and 42,000 μg/d (1,680,000 IU per day) over several days to months.

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> Your own link shows that what is considered toxic levels are far higher than most people would expect.

Unless, as mentioned, it had some traction as a cure all around the time of COVID.

This happens periodically and is again happening with vitamin C (which, whatever, getting to any dangerous amount might be physically impossible).

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Would you mind providing some examples? I can't say that I'm really up on a lot of psudoscience.

A pretty standard bottle of Vitamin D at 10k IU is 60 capsules/pills/whatever. That's a 2 month supply.

To hit the toxic eventually (77k IU) you would be going through a 2 month supply every ~7 days. To hit the acute toxicity in days or weeks (low end 600k), your going through that bottle every day.

However, every single time that someone mentions Vitamin D, people jump out of the woodwork about toxicity without ever actually bringing up just how much you have to take as if if you take the 400 IU capsule, going one IU over is going to kill you. I'm also pretty sure that a specific group of denialists shouldn't be counted as a reason to scream warnings from the mountaintops every time someone thinks about Vitamin D.

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> Would you mind providing some examples?

Sure. This is only going to be anecdotal and sparse examples, but this became a thing post-Covid, primarily as a "natural alternative" to vaccination.

Not just random people on random forums, Joe Rogan several times espoused the value of D along with other usual suspects:

"Rogan said he started feeling ill on Aug. 28 and tested positive the next day. He added he began taking his regimen the same day, which apparently included ivermectin, IV drips of vitamins D and C, nicotinamide adenine dinucleotide (NAD) that helps repair cells, and monoclonal antibodies. He said he felt fine the next day."

"Man Vomits For Months After Taking Vitamin D at Almost 400x Daily Recommended Dose"

https://www.news-medical.net/news/20220706/e28098Hypervitami...

https://www.sciencealert.com/man-overdoses-vomits-for-months...

Also unsurprisingly happened more often around this time with infants:

https://www.frontiersin.org/journals/pediatrics/articles/10....

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And, if you drink a glass of carrot juice a day, you'll receive toxic levels of vitamin A!

~40% of people don't get enough vitamin D [1]. It's not useful to categorize it as some trend, based on people just not following general recommended dosing (with more precise dosing depending entirely on personal sun exposure and skin color).

edit: As an office worker, I take 10k IU per day when I'm entirely indoors (most of the time), but vary it based on sun exposure. I based this on recent studies, and have my doctors approval with an exactly center-of-the-nominal-range vitamin D serum level.

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC9573946/

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> severe VDD was defined as serum 25(OH)D levels of <25 nmol/L, moderate deficiency as 25–50 nmol/L, insufficiency as 50–75 nmol/L, and sufficiency as >75 nmol/L.

These numbers seem high to me. The 75 nmol/L (30ng/L) is not really a reliable value. It was published in a research that raises many questions due to conflict of interests.

Hence the

> ~40% of people don't get enough vitamin D

becomes:

> ~40% of people in the USA don't get enough vitamin D according to Dr. Holick

Where I live the norm is 20 ng/L and if we apply that, then the shocking 40% becomes more reasonable 10-15%

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My doctor added vitamin D test to his patients recurring blood work since the start of COVID, and found out just about all his patients was deficient or near it.

If you don't have a primarily fish based diet or spend hours under direct overhead sunlight every day without a shirt on, you're probably deficient as well.

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That's a bit of an exaggeration, Vitamin D does not require hours in the sun:

> Recommendations to Obtain Adequate Amount of Vitamin D.

> Sun exposure to the face, arms, hands, and legs without sunscreen for 5 to 30 minutes at least twice a week or more between the hours of 10 am and 4 pm

Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC8299926/

Now that's for most people: if you live in Alaska then during the winter maybe you need a litle more or something ... but the point is most people just need a little sun, < 30 minutes twice a week.

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I'll say track and test yourself, since it depends highly on skin tone and weather.

That study also claims 12-20ng/mL 25-hydroxyvitamin D is sufficient. My doctor says the post-COVID studies suggest 75ng/mL is closer to optimal, and <30ng/mL had been considered deficient for about a decade before COVID.

Personally I had no problem hitting 20ng/mL through sunlight alone and I'm pretty fair skinned but live somewhere sunny. But I haven't been able to get anywhere near 75ng/mL even when I've made an effort to increase vitamin D through supplements and exposure to the sun.

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For several months of the year, vitamin D synthesis is near zero in latitudes as low as like 40° or 45°. Boston is 42°.

In Calgary, it's almost half the year that you basically cannot rely on the sun at all for vitamin D.

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I've also heard about it 'hardening' in the bloodstream and that you should really be taking it with K2 as well. This is anecdotal so someone please do more research than basing anything from this comment
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Roughly, Vitamine D3 make the body effective at extracting calcium from food and dumping it into the bloodstream; vitamin k2 make it easier for the body to use that calcium. Too D3 without K2 can cause hypercalcemia; K2 make it less likely but there is still a point where too much D3 is too much!

And too much D3 without calcium supplements make the body use the calcium from it's bones !

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