You are Using the Wrong Science. Vitamin D2 is equally as effective as Vitamin D3

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Study Says D2 is as Effective as D3

Comments for You are Using the Wrong Science. Vitamin D2 is equally as effective as Vitamin D3

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Not the wrong science, the wrong endpoint
by: Kerri Knox, RN- The Immune Health Queen

It's too bad that the person who wrote this didn't leave their email in order to get a response, because now they will just think that they 'told me so' and will never know the real answer to their question.

I hope that they subscribed to my RSS feed so that they will get an answer that way.

So, the answer that I have to this study is that is simply measured Vitamin D Levels in the blood. I have never disputed that Vitamin D2 IS effective at raising Vitamin D levels- although in other studies, it showed that it took MORE vitamin D2 to achieve effective blood levels.

Also, this study did NOT achieve recommended researcher 'optimal' levels of vitamin D between 40 to 80 ng/ml, so you don't know what would have happened at higher dosages.

But that is NOT the important part- vitamin D blood levels are not the ONLY endpoint to look at, although they are obviously the easiest and most readily available to test.

The most IMPORTANT endpoint in a TRUE comparison is disease prevention, but since that takes years to do a study, that most likely will never be done, but we DO have a PROXY for disease prevention- Vitamin D Receptor Activation.

Vitamin D Receptors- or VDR's as they are known- are dispersed WIDELY throughout the body and this may be responsible for why vitamin D has SO MANY different effects on different diseases. And while people think that disease is 'Genetic', many diseases are ONLY 'genetic' when the right (or wrong, I should say) genes are 'turned on'.

And one way that you can 'turn on' genes is to not have VDR's fully saturated with Vitamin D. In the study The Case Against Ergocalciferol the authors don't dispute that Vitamin D2 increases blood levels, but,

"Supplementation of vitamin D2 produces appreciable amounts of serum 25(OH)D2 (22), which, as previously mentioned, has a lower affinity for DBP [Vitamin D Binding Proteins] and results in a shorter circulating half-life than that of 25(OH)D3."


"In humans, previous work has shown that mitochondrial vitamin D 25-hydroxylase presides and converts vitamin D3 to 25(OH)D3- FIVE times as fast as it does vitamin D2 to form 25(OH)D2 "

And the gold standard: the authors state that the metabolites of Vitamin D2 have "less affinity for VDR than do" the metabolites of Vitamin D3.

So, if you JUST want to bring your levels up and NOT experience any of the OTHER benefits of Vitamin D, then feel free to take Vitamin D2- I'll stick with Vitamin D3.

Kerri Knox RN Immune Health Queen

Kerri Knox, RN- The Immune Health Queen
Functional Medicine Practitioner
Easy Immune

Had another thought...
by: Kerri Knox, RN- The Immune Queen!

The other day, I was thinking about an analogy to your study about simply raising Vitamin D Levels and not looking at any other end points.

You could also conclude that Statin Drugs work perfectly well because they reduce cholesterol. While they do, is that the only end point that you want to measure? What if Cholesterol Is All a Big Lie and that it is not really important for the reduction of heart disease?

Then would measuring cholesterol be a good 'endpoint' to measure? No. Of course not, you actually want to measure reduction of disease incidence and heart disease. But those kinds of studies take a very long time to do, so it's not likely that we'll get answers about that anytime soon.

But there are some doctors who believe that the disease end points and heart disease reduction claims of cholesterol lowering drugs just simply aren't true. Find out about what a renowned heart surgeon has to say about Cholesterol Levels Not the Problem and what we really SHOULD be measuring and trying to reduce instead!

So, Vitamin D Levels in and of themselves are NOT the be-all end-all of 'endpoints'. It is only one factor to consider when choosing which Vitamin D Preparation you will choose.

Kerri Knox RN Immune Health Queen

Kerri Knox, RN- The Immune Health Queen
Functional Medicine Practitioner
Easy Immune

by: Lindsey

I was prescribed 50,000 of D2 by my gastroenterologist. I had blood tests throughout the years and I still showed low vitamin D levels. When I asked the pharmacist, he said D3 is easier to metabolize and I should ask my doctor to switch over from D2 to D3. My doctor would not, so I purchased Andrew Lessman's D3 vitamins produced in sterile facilities in Henderson, Nevada.
If you want the truth about any drug prescription, ask an experienced and knowledgable pharmacist, don't ask your doctor.

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