(Thanks, p. :)

Reader peacefull sends us:

***************************************************************************

Re: link: 'Study now shows vitamin D recommend....

Using DRI's - A Vitamin D Case Study
http://nutrevolve.blogspot.ca/2015/03/using-dris-vitamin-d-case-study.html

mar 21

Back when I began taking dietetics courses, I kinda glossed over the way dietary
recommendations are set -they were just a bunch of acronyms to memorize. The older
I've gotten and more i've been involved in the literature, the more I see them as

some of the most critical things for clinicians to understand, because they're often
misinterpreted (in ways that I have been equally guilty of). This has been happening
a good bit in the literature recently, as it pertains to vitamin D. I'll
specifically be referencing a paper and relevant letter (1,2) in the open-access
journal, Nutrients (from the same publishing group that allowed the Seneff
glyphosate gish-gallop paper to be a thing).

Both this publication and the letter make 2 critical assumptions:

In Veugelers publication, they state that the IOM made a critical error in their
statistics, and set out to: "To illustrate the difference between the former and
latter interpretation, we estimated how much vitamin D is needed to achieve that
97.5% of individuals achieve serum 25(OH)D values of 50 nmol/L or more." For those
unfamiliar, 50nmol/L = 20ng/mL - both are the RDA.
In the corresponding letter, by Heaney et al, they perform an analysis of the
GrassRootsHealth database, and state that "The points at which these lines intersect
the lower bound of the 95% probability band for serum 25(OH)D reflect the inputs
necessary to ensure that 97.5% of the cohort would have a vitamin D status value at
or above the respective 25(OH)D concentration." For their analyses, they determined
that 3875 IU of vitamin D is needed to achieve at least 20 ng/mL (50 nmol/L) in
97.5% of the population is lower than the estimate of Veugelers and Ekwaru.
What these analyses fail to take into account is what we all learned back in
Nutrition 101. An RDA (3) is:

Recommended Dietary Allowance (RDA): average daily level of intake sufficient to
meet the nutrient requirements of nearly all (97%-98%) healthy people.
This value is the level estimated to meet the needs of about 97.5 percent of the
population. Anther way to think about this is looking at our typical bell curve (4).
If you got everyone in the population to the RDA blood level, in theory, 97.5
percent of them would have significantly more vitamin D than they need to meet their
needs. The goal with an RDA is to establish a level that would cover almost
everyone's needs, not to get every individual in the population to this blood level.
The IOM specifically addressed this the other day here -

"To be clear, the goal is not, and should not be, to assure that 97.5% of the
population exceeds the serum value linked to the RDA. Doing so would shift the
distribution to a higher level that is associated with increased risk for adverse
effects "

This is the critical error that Heaney and Veugeler make - they measure the amount
of vitamin D that would need to be taken in to get everyone in the population up to
the RDA blood level - but by definition, that amount is exceedingly high for most.

[big snip to end]

Full article:

http://nutrevolve.blogspot.ca/2015/03/using-dris-vitamin-d-case-study.html

*******************************************************************************************************************