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Did my masters on Vitamin D - It is very difficult to extract CLINICALLY RELEVANT information from retrospective epidemiological studies. However, there a a fe

Did my masters on Vitamin D - It is very difficult to extract CLINICALLY RELEVANT information from retrospective epidemiological studies. However, there a a few things that are clear: 1. Calcium absorption from the intestine increases with vitamin D supplementation dose up to around 8-10,000 IU D3 daily. 2. 15 minutes of full body exposure in noon sun is equivalent to a dose of ~20,000 IU D3 3. There are few cases of vitamin D overdose in the literature - doses in the 1,000,000 IU+ range within days is generally where symptoms are noted - this excludes people with kidney disorders. Personally, I take 10k IU D3 a day. The D3 is important because D2 has 1/2 to 1/3 the effect per dose in raising calcium absorption levels. I would recommend this level of supplementation to anyone who doesn’t have a kidney disorder.

anibalin 6y ago
Hi trevor, super intereseting what you mention. Wondering where you did the master since its not common (at least in my country). Thanks man.
didgeoridoo 6y ago
Interesting, I've always heard of the calcium absorption effect as a negative aspect of D over-supplementation — I guess the theory is that it raises your blood calcium level too high, leading to arterial calcification? Is that effect overblown in your opinion?
- trevorkoob 6y ago
  In acute hypervitaminosis D, there can be organ calcification that has to be treated. These cases are rarely reported - one case occurred when the patient ingested crystalline vitamin D - dosing themselves in the range of 1-2 million IU D3 per day for weeks, and although there was not an extensive follow-up to determine the long-term effect on the patient, the acute calcification was reversed with treatment. Vitamin D is involved with calcium in the body in many different ways, specifically I was talking about a measure of the absorption of calcium into the body from food as promoted by vitamin D. Organ calcification is extremely serious and a very understandable reason why doctors have been hesitant to recommend higher doses of vitamin D, however most medical thinking about vitamin D until recently has focused on the prevention of Rickets, which requires only a small amount of constant supplementation (500 IU D3) to avoid serious effects. In context, 10,000 IU seems like an enormous dose. However if you look at the blood serum levels of people who receive consistent UV exposure, they have much higher levels than someone who is being supplemented with 500 IU D3 and no UV. So much of this debate is around trying to find out what the "optimal" vitamin D level is rather than what level is "sufficient" to prevent Rickets.
- _0ffh 6y ago
  Not an expert, but from what I read that is exactly why you should not supplement high dosage vitamin D without also supplementing vitamin K2 (mk7 all-trans). Studies that show positive health effects from D3 typically supplement 40ug K2 for every 1000IU D3.
elric 6y ago
Re #2: the figure gets thrown around a lot. But who is outside, naked, at noon for fifteen minutes? It's really hard to translate that to anything meaningful or actionable. Here's a tool that can help calculate useful exposure depending on your location/time of year. Doesn't take clothing into account however.. https://fastrt.nilu.no/VitD-ez_quartMEDandMED_v2.html https://fastrt.nilu.no/VitD-ez_quartMEDandMED_v2.html
- ip26 6y ago
  Skin shade, location, time of year, and atmospheric conditions are other huge variables. My pale skin in the midday desert sun for fifteen minutes in July? I'd have a pretty serious burn.
  - minton 6y ago
    Your skin may be burned but you wouldn’t likely have a vitamin D overdose.
    - deleted 6y ago
      [deleted]
  - abstractbarista 6y ago
    You must be really pale. I'm super pale and it takes at least twice as long to start a light burn.
    - ip26 6y ago
      I'm not that pale but it's shocking how fast you can burn in some places. Denver, for example, has a mile less atmosphere protecting you and little UV-blocking humidity. While New Zealand famously has the ozone hole. I don't burn nearly as fast in San Francisco.
- travisoneill1 6y ago
  The point is that being outside naked at noon every day for 15 minutes wouldn't hurt you. Therefore, a daily dose of 20,000 IU / day won't hurt you. Therefore, a 5000 IU supplement every day won't hurt you either.
mrfusion 6y ago
Will your body make vitamin d from sunlight if you already have a enough from a supplement? I’m worried about overdosing if I take 5000 UI and get a lot of sun.
- AnonC 6y ago
  No, it won’t, but that’s only after a certain limit that’s much higher than 5000IU. Even if you spend all day in the sun, your body will stop the synthesis at a certain level (10000IU in the day is what I had read long ago, but that may be incorrect or outdated). In other words, 5000IU is much lower than what the body would naturally produce when exposed to sunlight for long durations in a day (assuming good latitude, sunny season, lower atmospheric pollution, around noon, lighter skin tone, etc.).
- trevorkoob 6y ago
  I personally aim for 10,000 IU D3 daily from either sun or supplement. In normal times, living in New York, I would supplement 10,000 IU D3 from November through March, and then I would make sure to be outside 1 hour a day with at least arms and face exposed. Shots of 250,000 IU are given clinically and the therapeutic dose was traditionally 50,000 IU D2 weekly - corresponding to a dose of about 3,500 IU D3 daily. I highly recommend getting tested for kidney disease if you are worried and get multiple vitamin D tests - the tests are imprecise but will give you a general idea of what your levels are.
dehrmann 6y ago
When my vitamin D levels tested a little low, I asked my doctor about it, and he said studies don't show any benefit for supplementing vitamin D deficiencies that are asymptomatic. At the time, I looked up the study, though I can't seem to find it now.
- AlexanderNull 6y ago
  The studies I've seen relaying the same sentiment of no appreciable benefit only looked at a single outcome, normally bone density or bone fracture occurrence. Vitamin D levels affect expression of almost 300 different genes in humans (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3604145/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3604145/) so looking at a single outcome to gauge the entire efficacy of that vitamin is absurd and disappointing that so many other doctors push their narrow minded interpretations of those same limited studies.
  - trevorkoob 6y ago
    My thesis argued that we should not be testing supplementation levels, instead we should be testing the effects of maintaining people at various serum levels of vitamin D year-round.
prox 6y ago
Do you know what would the baseline vitamine D intake been for our ancient (read : outdoor lifestyle) ancestors?
- trevorkoob 6y ago
  It depends - ancient ancestors had a lot of different lifestyles. For example, Soranus of Ephesus reported deformations in the bones of children as early as the 100 CE. However, this is I think what you are trying to get at: One particular epidemiological study stands out as a guide for what typical 25-(OH)D levels might have been be for our earliest ancestors. Luxwolda et al. studied populations of pastoral Masai and hunter-gatherer Hadzabe, sampling their blood for 25-(OH)D levels and taking note of their daily habits in reference to UV exposure. The mean 25-(OH)D concentration in these populations was 115 nmol/L, with a range of 58 nmol/L to 171 nmol/L. This study provides a general framework for the expected 25-(OH)D level of active, healthy humans working outdoors at a low (< 5 degrees) latitude. Humans have modified their living conditions greatly from this model of ancestral life, leading to reduced exposure to UV radiation.
  - prox 6y ago
    Thank you for your answer, that is pretty interesting!
    - trevorkoob 6y ago
      Welcome! I highly recommend the study - even though the numbers are low, the data is very interesting.
Abishek_Muthian 6y ago
>this excludes people with kidney disorders. Can increased calcium absorption lead to kidney disorders? This is my biggest worry when taking Vitamin D3 supplements, I have Vitamin D deficiency but when I take supplements it quickly reaches to toxicity levels (> 80 ng/mL) and so I have the revert to monthly supplement of 60,000 IU of Cholecalciferol. PSA: I'm a dwarf, possibly Achondroplasia, but during childhood (4 - 15years) I wasn't categorised as such and my bone troubles were always attributed to Vitamin D deficiency. After age 17, I didn't have much of bone problems and so I didn't follow up on my Vitamin D deficiency. Fast forward to age 32, I was diagnosed with Spinal Stenosis among other cerebral spinal fractures risking becoming quadriplegic[1]. So, if you have bone problems due to Vitamin D deficiency, please follow it up regularly, it's likely going to be life-long but taking proper supplements is better than a fracture. Also visiting a good endocrinologist to get to the root of Vitamin D problems is recommended. [1]https://abishekmuthian.com/i-was-told-i-would-become-quadriplegic-68c0371e6f05/ https://abishekmuthian.com/i-was-told-i-would-become-quadrip...
- radu_floricica 6y ago
  IANAD, but the word is you should couple it with vitamin K to offset the extra calcium absorption. Which is a good idea on general principles, since K is one of the other very few supplements worth taking by the gen pop.
- trevorkoob 6y ago
  There are many cases of kidney disorders causing issues in vitamin D metabolism - the majority of literature examples I read involved genetic kidney disorders which would not be be caused by increased calcium absorption. I hope you are receiving the treatment you need.
gregwebs 6y ago
This is really dangerous advice to be peddling on internet forums. Statements 1 & 2 are both misleading. It is certainly true that a few high dosages of vitamin D are not harmful. The issue is the negative effects of having too high of a vitamin D status. Anyone taking more than 2k IU/day should do so after consulting their doctor or at least testing of their vitamin D levels.
- northern-lights 6y ago
  Not sure why this is being downvoted. This advice is far more useful than OPs. Be careful of anyone claiming to be an expert on anything, especially on an anonymous forum - even if that forum has in general higher quality opinion. And the OP does not mention Vitamin K2 at all. How does anybody who claims to have done a Masters on Vitamin D not mention K2?
  - trevorkoob 6y ago
    I didn't mention K2 because I didn't study it. I make no claim to expertise, only familiarity. Personally, I eat dark green leafy vegetables every day - one serving of kale contains 443% daily value of vitamin K and I probably consume 2-3 servings a day. Most food we eat doesn't contain vitamin D. A serving of farmed salmon, for example, contains about 250 IU D3 - 32% of the daily value. In any case, I highly agree with not trusting anonymous internet opinions.
- semerda 6y ago
  And your statement is wiser because? I've been taking vitamin d3 10K IU/day for 10 years and it has allowed my blood V-D3 levels to go from 12 ng/mL to ~50 which is within normal range. The NIH recommended dose has been going up over the last 2 decades starting at 400 IU and now 4,000 IU as we learn more and more about it's effectiveness.
  - gregwebs 6y ago
    The NIH states that 4000 IU is the tolerable upper intake: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/ https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessiona... If you are rounding down your vitamin D status then it is currently at what the NIH say should be avoided. Have you consulted with a medical professional about your vitamin d status? 10k IU/day can be great when someone's level is 12, but it's not a maintenance dosage once at healthy levels.
AnonC 6y ago
> 2. 15 minutes of full body exposure in noon sun is equivalent to a dose of ~20,000 IU D3 For someone who claims to have done a masters on Vitamin D, I find this generalized statement disturbing. What skin tone the person has, what season it is, what latitude the person lives at, age of the person etc., are factors in how much Vitamin D is produced by the body on exposure to sunlight. I’m afraid I can’t take the other points seriously because of the brevity and lack of nuance.
- trevorkoob 6y ago
  Yes, this was overly brief and a tilde is not enough to qualify this statement, and I should have said noon equatorial sun. My point here was meant to be about how this is essentially the daily maximum dose from UV radiation due to the isomerization of previtamin D into inactive isomers, and to give context to a dose of 10,000 IU D3 seeming large when it is half the amount a person might receive from sun exposure.
eli_gottlieb 6y ago
>2. 15 minutes of full body exposure in noon sun is equivalent to a dose of ~20,000 IU D3 Define "full-body exposure", please? I'm not going to walk around naked outside in the sun.
semerda 6y ago
Ditto re 10K. I've been taking Vitamin D3 10K IU/day for 10 years and it has allowed my blood V-D3 levels to go from 12 ng/mL to ~50 which is within normal range. The NIH recommended dose has been going up over the last 2 decades starting at 400 IU and now 4,000 IU as we learn more and more about it's effectiveness. Re lux with full body exposure. I was under the impression it's an hour per day to get 15-20 IU? Either way it means exposing legs, hands and face to the sun which most people rarely do on a daily basis.
cachestash 6y ago
I calcium absorption increases, should you also supplement calcium?
jungletime 6y ago
I knew people that would go for a walk during lunch around the office building with a friend. Ate a packed sandwich, got a walk in, a conversation, and apparently got a much needed dose of D3. Seems like such a low effort, high reward thing to do. Depending on the latitude and skin complexion that may be all thats needed for D3.

anibalin 6y ago

Hi trevor, super intereseting what you mention. Wondering where you did the master since its not common (at least in my country). Thanks man.

didgeoridoo 6y ago

Interesting, I've always heard of the calcium absorption effect as a negative aspect of D over-supplementation — I guess the theory is that it raises your blood calcium level too high, leading to arterial calcification? Is that effect overblown in your opinion?

trevorkoob 6y ago
In acute hypervitaminosis D, there can be organ calcification that has to be treated. These cases are rarely reported - one case occurred when the patient ingested crystalline vitamin D - dosing themselves in the range of 1-2 million IU D3 per day for weeks, and although there was not an extensive follow-up to determine the long-term effect on the patient, the acute calcification was reversed with treatment. Vitamin D is involved with calcium in the body in many different ways, specifically I was talking about a measure of the absorption of calcium into the body from food as promoted by vitamin D. Organ calcification is extremely serious and a very understandable reason why doctors have been hesitant to recommend higher doses of vitamin D, however most medical thinking about vitamin D until recently has focused on the prevention of Rickets, which requires only a small amount of constant supplementation (500 IU D3) to avoid serious effects. In context, 10,000 IU seems like an enormous dose. However if you look at the blood serum levels of people who receive consistent UV exposure, they have much higher levels than someone who is being supplemented with 500 IU D3 and no UV. So much of this debate is around trying to find out what the "optimal" vitamin D level is rather than what level is "sufficient" to prevent Rickets.
_0ffh 6y ago
Not an expert, but from what I read that is exactly why you should not supplement high dosage vitamin D without also supplementing vitamin K2 (mk7 all-trans). Studies that show positive health effects from D3 typically supplement 40ug K2 for every 1000IU D3.

elric 6y ago

Re #2: the figure gets thrown around a lot. But who is outside, naked, at noon for fifteen minutes? It's really hard to translate that to anything meaningful or actionable. Here's a tool that can help calculate useful exposure depending on your location/time of year. Doesn't take clothing into account however.. https://fastrt.nilu.no/VitD-ez_quartMEDandMED_v2.html https://fastrt.nilu.no/VitD-ez_quartMEDandMED_v2.html

ip26 6y ago
Skin shade, location, time of year, and atmospheric conditions are other huge variables. My pale skin in the midday desert sun for fifteen minutes in July? I'd have a pretty serious burn.
- minton 6y ago
  Your skin may be burned but you wouldn’t likely have a vitamin D overdose.
  - deleted 6y ago
    [deleted]
- abstractbarista 6y ago
  You must be really pale. I'm super pale and it takes at least twice as long to start a light burn.
  - ip26 6y ago
    I'm not that pale but it's shocking how fast you can burn in some places. Denver, for example, has a mile less atmosphere protecting you and little UV-blocking humidity. While New Zealand famously has the ozone hole. I don't burn nearly as fast in San Francisco.
travisoneill1 6y ago
The point is that being outside naked at noon every day for 15 minutes wouldn't hurt you. Therefore, a daily dose of 20,000 IU / day won't hurt you. Therefore, a 5000 IU supplement every day won't hurt you either.

mrfusion 6y ago

Will your body make vitamin d from sunlight if you already have a enough from a supplement? I’m worried about overdosing if I take 5000 UI and get a lot of sun.

AnonC 6y ago
No, it won’t, but that’s only after a certain limit that’s much higher than 5000IU. Even if you spend all day in the sun, your body will stop the synthesis at a certain level (10000IU in the day is what I had read long ago, but that may be incorrect or outdated). In other words, 5000IU is much lower than what the body would naturally produce when exposed to sunlight for long durations in a day (assuming good latitude, sunny season, lower atmospheric pollution, around noon, lighter skin tone, etc.).
trevorkoob 6y ago
I personally aim for 10,000 IU D3 daily from either sun or supplement. In normal times, living in New York, I would supplement 10,000 IU D3 from November through March, and then I would make sure to be outside 1 hour a day with at least arms and face exposed. Shots of 250,000 IU are given clinically and the therapeutic dose was traditionally 50,000 IU D2 weekly - corresponding to a dose of about 3,500 IU D3 daily. I highly recommend getting tested for kidney disease if you are worried and get multiple vitamin D tests - the tests are imprecise but will give you a general idea of what your levels are.

dehrmann 6y ago

When my vitamin D levels tested a little low, I asked my doctor about it, and he said studies don't show any benefit for supplementing vitamin D deficiencies that are asymptomatic. At the time, I looked up the study, though I can't seem to find it now.

AlexanderNull 6y ago
The studies I've seen relaying the same sentiment of no appreciable benefit only looked at a single outcome, normally bone density or bone fracture occurrence. Vitamin D levels affect expression of almost 300 different genes in humans (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3604145/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3604145/) so looking at a single outcome to gauge the entire efficacy of that vitamin is absurd and disappointing that so many other doctors push their narrow minded interpretations of those same limited studies.
- trevorkoob 6y ago
  My thesis argued that we should not be testing supplementation levels, instead we should be testing the effects of maintaining people at various serum levels of vitamin D year-round.

prox 6y ago

Do you know what would the baseline vitamine D intake been for our ancient (read : outdoor lifestyle) ancestors?

trevorkoob 6y ago
It depends - ancient ancestors had a lot of different lifestyles. For example, Soranus of Ephesus reported deformations in the bones of children as early as the 100 CE. However, this is I think what you are trying to get at: One particular epidemiological study stands out as a guide for what typical 25-(OH)D levels might have been be for our earliest ancestors. Luxwolda et al. studied populations of pastoral Masai and hunter-gatherer Hadzabe, sampling their blood for 25-(OH)D levels and taking note of their daily habits in reference to UV exposure. The mean 25-(OH)D concentration in these populations was 115 nmol/L, with a range of 58 nmol/L to 171 nmol/L. This study provides a general framework for the expected 25-(OH)D level of active, healthy humans working outdoors at a low (< 5 degrees) latitude. Humans have modified their living conditions greatly from this model of ancestral life, leading to reduced exposure to UV radiation.
- prox 6y ago
  Thank you for your answer, that is pretty interesting!
  - trevorkoob 6y ago
    Welcome! I highly recommend the study - even though the numbers are low, the data is very interesting.

Abishek_Muthian 6y ago

>this excludes people with kidney disorders. Can increased calcium absorption lead to kidney disorders? This is my biggest worry when taking Vitamin D3 supplements, I have Vitamin D deficiency but when I take supplements it quickly reaches to toxicity levels (> 80 ng/mL) and so I have the revert to monthly supplement of 60,000 IU of Cholecalciferol. PSA: I'm a dwarf, possibly Achondroplasia, but during childhood (4 - 15years) I wasn't categorised as such and my bone troubles were always attributed to Vitamin D deficiency. After age 17, I didn't have much of bone problems and so I didn't follow up on my Vitamin D deficiency. Fast forward to age 32, I was diagnosed with Spinal Stenosis among other cerebral spinal fractures risking becoming quadriplegic[1]. So, if you have bone problems due to Vitamin D deficiency, please follow it up regularly, it's likely going to be life-long but taking proper supplements is better than a fracture. Also visiting a good endocrinologist to get to the root of Vitamin D problems is recommended. [1]https://abishekmuthian.com/i-was-told-i-would-become-quadriplegic-68c0371e6f05/ https://abishekmuthian.com/i-was-told-i-would-become-quadrip...

radu_floricica 6y ago
IANAD, but the word is you should couple it with vitamin K to offset the extra calcium absorption. Which is a good idea on general principles, since K is one of the other very few supplements worth taking by the gen pop.
trevorkoob 6y ago
There are many cases of kidney disorders causing issues in vitamin D metabolism - the majority of literature examples I read involved genetic kidney disorders which would not be be caused by increased calcium absorption. I hope you are receiving the treatment you need.

gregwebs 6y ago

This is really dangerous advice to be peddling on internet forums. Statements 1 & 2 are both misleading. It is certainly true that a few high dosages of vitamin D are not harmful. The issue is the negative effects of having too high of a vitamin D status. Anyone taking more than 2k IU/day should do so after consulting their doctor or at least testing of their vitamin D levels.

northern-lights 6y ago
Not sure why this is being downvoted. This advice is far more useful than OPs. Be careful of anyone claiming to be an expert on anything, especially on an anonymous forum - even if that forum has in general higher quality opinion. And the OP does not mention Vitamin K2 at all. How does anybody who claims to have done a Masters on Vitamin D not mention K2?
- trevorkoob 6y ago
  I didn't mention K2 because I didn't study it. I make no claim to expertise, only familiarity. Personally, I eat dark green leafy vegetables every day - one serving of kale contains 443% daily value of vitamin K and I probably consume 2-3 servings a day. Most food we eat doesn't contain vitamin D. A serving of farmed salmon, for example, contains about 250 IU D3 - 32% of the daily value. In any case, I highly agree with not trusting anonymous internet opinions.
semerda 6y ago
And your statement is wiser because? I've been taking vitamin d3 10K IU/day for 10 years and it has allowed my blood V-D3 levels to go from 12 ng/mL to ~50 which is within normal range. The NIH recommended dose has been going up over the last 2 decades starting at 400 IU and now 4,000 IU as we learn more and more about it's effectiveness.
- gregwebs 6y ago
  The NIH states that 4000 IU is the tolerable upper intake: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/ https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessiona... If you are rounding down your vitamin D status then it is currently at what the NIH say should be avoided. Have you consulted with a medical professional about your vitamin d status? 10k IU/day can be great when someone's level is 12, but it's not a maintenance dosage once at healthy levels.

AnonC 6y ago

> 2. 15 minutes of full body exposure in noon sun is equivalent to a dose of ~20,000 IU D3 For someone who claims to have done a masters on Vitamin D, I find this generalized statement disturbing. What skin tone the person has, what season it is, what latitude the person lives at, age of the person etc., are factors in how much Vitamin D is produced by the body on exposure to sunlight. I’m afraid I can’t take the other points seriously because of the brevity and lack of nuance.

trevorkoob 6y ago
Yes, this was overly brief and a tilde is not enough to qualify this statement, and I should have said noon equatorial sun. My point here was meant to be about how this is essentially the daily maximum dose from UV radiation due to the isomerization of previtamin D into inactive isomers, and to give context to a dose of 10,000 IU D3 seeming large when it is half the amount a person might receive from sun exposure.

eli_gottlieb 6y ago

>2. 15 minutes of full body exposure in noon sun is equivalent to a dose of ~20,000 IU D3 Define "full-body exposure", please? I'm not going to walk around naked outside in the sun.

semerda 6y ago

Ditto re 10K. I've been taking Vitamin D3 10K IU/day for 10 years and it has allowed my blood V-D3 levels to go from 12 ng/mL to ~50 which is within normal range. The NIH recommended dose has been going up over the last 2 decades starting at 400 IU and now 4,000 IU as we learn more and more about it's effectiveness. Re lux with full body exposure. I was under the impression it's an hour per day to get 15-20 IU? Either way it means exposing legs, hands and face to the sun which most people rarely do on a daily basis.

cachestash 6y ago

I calcium absorption increases, should you also supplement calcium?

jungletime 6y ago

I knew people that would go for a walk during lunch around the office building with a friend. Ate a packed sandwich, got a walk in, a conversation, and apparently got a much needed dose of D3. Seems like such a low effort, high reward thing to do. Depending on the latitude and skin complexion that may be all thats needed for D3.