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Posted on: August 6, 2012
by Rebecca Oshiro
An editorial published in this month’s issue of Circulation examined the evidence for the role of vitamin D in lipid profiles.
Jorde R, Grimnes G. Vitamin d and lipids: do we really need more studies? Circulation. 2012;126(3):252-4. You must be a paid member to read the rest of this post. Please login or register now.
Is anyone still using D2 in experimentation?
D2 is an example of where pharmaceutical dominance/manipulation has caused a lot of confusion and possibly negative results
Ian, I looked into the meta-analysis cited here and found that it analyzed the results of 12 RCT’s. Of these 12, 7 used D3 and the remaining used either D2, alpha-calcidol, or calcitriol. Studies administering a daily dose of vitamin D dosed anywhere from 300 to 3332 IU/day. Two of the studies administered a single, large dose and one administered vitamin D to participants every two weeks. Duration ranged anywhere from 42 days to 3 years.
Only 6% of the people has an increase in vitamin D levels.
Here are some of the reasons for increased vitamin D levels
Have recovered from surgery
Have recovered from trauma
Have recovered from a burn
Have recovered from Cancer
Have recovered from pregnancy
Have recovered from Earthquake trauma
Had more sunshine (vacation, season, etc.)
Stopped medications which had reduced vitamin D levels
Gut absorption no longer a problem
Kidney operating again perhaps transplant
Supplementation (D2, D3, etc)
– – – Details at http://www.vitamindwiki.com/tiki-index.php?page_id=3010
Why is supplementation with D2 even permissable, at all, in these scientific studies? What type of studies support D2 as helpful, in any capacity, as compared to D3?
Good question Margaret. I would say that D2 supplementation in RCTs is becoming rarer and rarer (though you’ll still see them from time to time), but in meta-analysis, D2 trials will always pop up as we look at past trials.
I have spoken to one researcher who could only use D2 in his trial; something about needing to get the product from a pharmacy for IRB approval(?), and as you know, pharmacies usually only stock D2. Perhaps a researcher here cares to offer some insight on why using D2 in trials would be more convenient for their protocol?
“Supplemental vitamin D is available in 2 distinct forms: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). Pharmacopoeias have officially regarded these 2 forms as equivalent and interchangeable, yet this presumption of equivalence is based on studies of rickets prevention in infants conducted 70 y ago. The emergence of 25-hydroxyvitamin D as a measure of vitamin D status provides an objective, quantitative measure of the biological response to vitamin D administration. As a result, vitamin D3 has proven to be the more potent form of vitamin D in all primate species, including humans. Despite an emerging body of evidence suggesting several plausible explanations for the greater bioefficacy of vitamin D3, the form of vitamin D used in major preparations of prescriptions in North America is vitamin D2. The case that vitamin D2 should no longer be considered equivalent to vitamin D3 is based on differences in their efficacy at raising serum 25-hydroxyvitamin D, diminished binding of vitamin D2 metabolites to vitamin D binding protein in plasma, and a nonphysiologic metabolism and shorter shelf life of vitamin D2. Vitamin D2, or ergocalciferol, should not be regarded as a nutrient suitable for supplementation or fortification. ”
Our in-home Vitamin D Test Kit is easy, affordable, and an accurate way to find out your Vitamin D status.
A recent open label trial found that higher doses of vitamin D in infants reduced duration of influenza symptoms.