My Vitamin D followup, 14.5 years later

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Sep 30, 2020
The Vitamin D episode of Security Now took place almost 14.5 years ago, and I wanted to pass along my thanks. At the time that it "aired", I suffered from colds twice a year. That next year, after increasing my Vitamin D intake? Zero colds. The year after that? Zero colds. In those intervening 14.5 years, I've only had three colds, with no other major changes to diet or lifestyle. I acknowledge that this isn't *proof* that Vitamin D is why I almost never have colds anymore, but it is evidence, and I believe it to be so. So, THANK YOU @Steve for pointing me in the right direction!

I started out taking an average of around 2000 to 4000 IU per day, and when I had the doctor check my Vitamin D blood level back in 2015, it was 32.0, with normal being 30 to 100. I upped my intake to 5000 IU per day (though I still occasionally miss), and am looking forward to getting it checked again soon.

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Cool feedback, @DrBunsen, thanks for that. (y) I'm also taking 5000IU/day which puts my blood level right in the sweet spot. And as you know from that podcast, since Vitamin D3 is fat soluble, missing a day from time to time should have negligible effect.
@Steve I wasn't sure if the doctor's appointment I had yesterday was going to include blood work (it did), and I requested that they check my Vitamin D level, just to make sure I wasn't taking TOO much supplement. The report I got back today said it was at 68, with optimal levels being between 30 and 100. So I'm apparently doing fine taking 5000 IU most days. :) Thanks again!
Yes! I'd say that's really ideal. As you may recall the high of 100 is entirely arbitrary. We know that too much Vitamin D3 can be toxic, but there's never been any actual attempt to determine where toxicity begins to occur. So 100 was set since it's a nice round number and appears to be safe. My sense has been that being nearer to the upper end of that range is better than being "barely sufficient."

Note: For anyone reading this who may have been made curious, here's the page I created way back then at GRC which contains links to the audio and some additional info: Vitamin D3 is so inexpensive (and so tiny in size to take daily), and it can make such a profound difference in immune-related health, that it's really a no-brainer. (y)
I would like to know what other supplements people are taking. I try to take 6000 IU of D type 3 everyday and I take 3,000 mg of fish oil. The last time I had blood work, which was in September, they told me my protein was way to low. I’ve started to try and consume at least 100 g of protein per day and started in late December, hopefully I will get some blood work done this month and find out if I have helped the situation. I often forget to my D and fish oil, anyone with that problem I find using an app on your phone that gives little beeps or buzzes to remind you to take your D or whatever is helpful.
My Doc got my D3 blood test back today and I was at 90.30 which caused them to say oh no, the top is 50, you are taking too much.

I am taking one Now foods 5000 daily as I have been since Steve did that fantastic D3 investigation podcast.

What I find confusing that on the D3 blood test report (below) from Quest Diagnostics it has my result and the guidelines below (Note the 2011 date reference):
Vitamin D, 25-Hydroxy, Total 90.30 ≥20.00 ng/mL

Vitamin D, 25-OH, Total:
<10 ng/mL Severe Deficiency
10 - 19 ng/mL Mild/Moderate Deficiency
20 - 50 ng/mL Optimum
51 - 150 ng/mL Increased Risk of Hypercalciuria
>150 ng/mL Possible Toxicity Reference intervals apply to males and females, all ages.
Clinical decision values based on 2011 report by the Institute of Medicine (US).
Then on Quest Diagnostics web page (below) it has the range 30 to 100:
---------------------------------------------------------------------- levels,ng/mL are considered optimal.

What do vitamin D tests measure?1,2​

Vitamin D tests, which include immunoassays and liquid chromatography-mass spectrometry LC/MS/MS, measure the level of 25(OH)D, the main form of circulating vitamin D.

Optimal levels​

Vitamin D levels of 30 to 100 ng/mL are considered optimal.

Is everyone testing and getting a number that alerts their Doctor based on a 2011 report by the Institute of Medicine? :)

I don't want "Increased Risk of Hypercalciuria". Maybe that's where taking the K2 MK7 comes in to play?

I was thinking maybe skip taking the D3 5000 on Sundays and use something like Walk In Labs to test my self in a few months?

I don't want to give up the benefits of having my D3 in the good side of the range, what ever the range is.


@Dick: I would never counsel anyone to ignore the advice and instructions of their own medical professionals. They are the ones who will be there for you if/when you need them. But from the research I did 20 years ago into Vitamin D, I recall quite clearly that the upper limit of 100 ng/ml was set arbitrarily and was not based upon the results of any studies or research. And anecdotally, many young shirtless lifeguards and young workers whose job it is to re-roof buildings have naturally occurring levels close to 100 ng/ml.

Based upon everything I've seen, there's no reason for panic. But neither is there any known reason for you to “operate” with such a high level when it would be easier for you to drop to any lower dosage:

4000IU D3 + K-2:
1000IU D3 + K-2:

You could go with the 1000IU dosage and take two per day (since they're inexpensive and tiny) and measure in 6 months or a year from now to see where that puts your blood levels.
Thanks Steve, I like that idea of one morning and one evening of the Now D3 1000's with the K2 MK4 that will also diversify my K2 in to MK4 as well as the 100mcg of MK7 I started last week. I'll test again in a few months to make sure my D3 is not falling to far.
@ShadowMeow How long have you been taking the 10,000IU D3 and have you done a blood test for your D3 level?
Also were you taking the K complex during that time?
@ShadowMeow How long have you been taking the 10,000IU D3 and have you done a blood test for your D3 level?
Also were you taking the K complex during that time?
I only take the D3 in the winter months. I don't take the K complex. Never had a blood test done.