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Most of the patients I see with vitamin D toxicity are on 5000 units daily or more. And it can take a while (years) for toxicity to occur. Vitamin D builds up during that time since it is fat-soluble. If you want to take Vitamin D over a long period of time, at least check your levels.
Another case-study that may be of interest has some information on effects of elevated Vitamin D levels on the kidneys: "In terms of renal involvement, hypercalcemia can cause kidney injury both acutely and chronically. Hypercalcemia can cause acute kidney injury primarily by 2 mechanisms: afferent arteriolar constriction and intravascular volume depletion from a diuretic effect through activation of calcium-sensing…
> The patient’s calcium and vitamin D levels decreased after initiation of hydroxychloroquine. Almost 1 year after diagnosis, his calcium and vitamin D levels have returned to normal, but he is left with stage 3B (estimated glomerular filtration rate 34 mL/min/1.73m3) chronic kidney disease.
For those interested in Vitamin D and Covid, here is a summary of the research so far: https://www.devaboone.com/post/vitamin-d-and-covid
Seems like a no brainer to encourage people to start taking vitamin d now as it clearly at least has a small positive effect against covid
Earlier quoted context omitted.
"One International Unit (IU) equals 0.025 mcg of cholecalciferol (Vitamin D3) or of ergocalciferol (Vitamin D2)" [1] [1] https://walrus.com/questions/converting-units-iu-of-vitamin-...
Hmm, so 2000IU. That doesn’t seem like a lot, but I guess it really depends on the person.
The title doesn’t match the abstract. This isn’t a study of the tolerable upper limit of Vitamin D intake. It’s a case report of a single individual who was taking astronomical doses of Vitamin D with disastrous consequences. It’s certainly possible to take too much vitamin D without coming anywhere near the silly doses this person was consuming. Anyone taking aggressive vitamin D doses should invest in a vitamin D t…
Megadosing B12 (if your diet isn't already sufficient in it, which is common amongst certain vegan diets) is still a good idea, no? I recognize this might be the only exception.
For example, elevated B12 levels are associated with increased lung cancer risk in a dose-response fashion: https://pubmed.ncbi.nlm.nih.gov/30499135/
The only time megadosing B12 is a good idea is if you have confirmed low levels via a blood test and need to quickly raise your levels to the normal range.
Don’t assume you can guess your B12 status by reading random articles on the Internet. Low B12 has become a favorite hypothesis among the alternate medicine crowd, so online information about B12 supplementation has become corrupted with pseudoscience.
I’ll admit that I fell for the idea that B12 deficiency was rampant due to modern diets. Then I got a blood test and discovered that my B12 levels were toward the upper end of the reference range already.
On the bright side, B12 absorption is very nonlinear. A megadose might only cause slightly more absorption than what you find in a regular multivitamin. Most of the megadose is simply not absorbed.
I see Vitamin D toxicity at MUCH lower doses than in this case report. Here is my description of one patient: https://www.devaboone.com/post/vitamin-d-part-2-shannon-s-st... Most of the patients I see with vitamin D toxicity are on 5000 units daily or more. And it can take a while (years) for toxicity to occur. Vitamin D builds up during that time since it is fat-soluble. If you want to take Vitamin D over a long per…
I’m also concerned with the unbounded enthusiasm for Vitamin D supplementation in the wake of all the COVID news. The two most common mistakes I see online are:
1) Not understanding the long elimination times of these vitamins. When overdose can take months or years to appear due to gradual accumulation, it becomes difficult to associate health problems with slowly increasing vitamin levels. Most people don’t realize that overdose won’t be immediately apparent.
2) Forgetting to account for dietary Vitamin D intake. The way some people talk about Vitamin D, you’d think that supplements and sunlight are the only way to get it. If these people added up all of the Vitamin D they received through their diet they might be surprised that their combined dietary plus supplemental Vitamin D intake is higher than they wanted.
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The trouble with Vitamin D is afaik, as with some other vitamins, that it is fat-soluble rather than water-soluble. So the excess of the Vitamin won't be flushed out through the urine - but rather accumulates in the fat. At some point this accumulation may lead to toxicity ("Hypervitaminosis D" [1]). Personally, I dose 4000-5000 IU D3+K2 in the darker seasons and that has been working well for me. Vitamin B12 is wate…
It's my understanding that oral availability is lower than IM, and that people who are deficient get 70,000 IU injections. I'm entirely untrained, but my amateur evaluation of the situation leads me to take 50,000 IU orally once each week or two. I imagine that twice that amount would be fine, too.
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Whether or not that's true, the article isn't talking about 4-5x the RDA. It's talking about massive doses beyond even the most aggressive supplementation, much less a normal days intake.
According to the paper she was indeed taking 325 times the recommended daily dose of Vitamin D for 20 months. The paper is indeed pretty silly. "How much is too much? Somewhere between 1x and 325x RDA apparently."
(It's true, I didn't read the article.)
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In Canada at least anything over 1,000 IU in a pill needs to be prescribed (at which point I think it is an injection but I might be wrong). You’ll never find larger for sale.
That's interesting, I just had a look at my local amazon in Germany and even 50k IU caps are easily available for a few euros. https://www.amazon.de/dp/B01H3U5ZVI/