Page 42 - Spring2009

and D are synergistic, he now states that vitamin would still be useful.
A antagonizes the actions of vitamin D. The Vita- Please supply us with this evidence. Where
min D Council report claims that the vitamin A in does the average American get vitamin A in the
cod liver oil is excessive and antagonizes vitamin modern diet? If vitamin A in the American diet
D by inhibiting the binding of its active form to is adequate for vitamin D activation, why are
DNA and thus prevents its ability to regulate the Cannell and Mercola obliged to recommend such
expression of vitamin D-responsive genes. high levels of vitamin D—levels much higher
Vitamins A and D are both precursors to than those found in traditional diets—in order
active hormones that regulate the expression of to bring serum vitamin D levels into the normal
genes. The body possesses certain enzymes that range?
convert each of these in a two-step process to their
active forms: vitamin A is converted to retinol MOST COD LIVER OILS HAVE EXCESSIVE
and then to active retinoic acid while vitamin D VITAMIN A (PREFORMED RETINOL)
is converted to calcidiol and then to active cal- However, even the Weston Price Foundation
citriol. While directly consuming either retinoic acknowledges that there are dangerous versions
acid or calcitriol would be unnatural, consuming of cod liver oil out there, even from some highly
vitamins A and D, together, as in cod liver oil, reputable companies like Nordic Naturals, which
is perfectly natural. The enzymes involved in produces a cod liver oil that is clearly excessive in
If vitamin A these conversions are responsible for producing vitamin A as it only has 3 to 60 units of vitamin D
in the incredibly powerful hormones and are therefore per tablespoon but between 150 and 12,000 times
American diet highly regulated. as much vitamin A. It’s a delicate balance.
In order for vitamin D to activate the expres-
Both vitamins are essential to obtain optimal
is adequate sion of its target genes, it must bind to the vitamin health benefits, however, the ratios can become
for vitamin D D receptor (VDR) and then combine with the dangerously unbalanced—much like the omega-
retinoid X receptor (RXR), which is activated by 3/omega-6 balance, which has become inversed
activiation, a particular form of vitamin A called 9-cis retinoic in our modern diet.
why are acid. Researchers from Spain recently showed Nearly all brands of cod liver oil provide
Cannell and that vitamin D can only effectively activate target a token amount of vitamin D, typically a mere
genes when its partner receptor is activated by 400 to 1,200 IU of vitamin D per tablespoon but
Mercola vitamin A. anywhere between 4,000 to 30,000 IU of vitamin
obliged to The Weston Price Foundation, of which I A. This is clearly inappropriate. About the lowest
recommend am an advisory [honorary] member, holds a ratio I have seen is ten times as much vitamin A
such high lev- contradictory view. They believe vitamin D can as vitamin D but, as I stated above, it can be as
only effectively target genes when its “partner high as 12,000 times as much vitamin A.
els of receptor” is activated by vitamin A. If vitamin A First of all, this is clearly an insufficient

vitamin D— is absent, certain molecules called co-repressors amount of vitamin D for even the smallest child.
bind to the receptors and prevent vitamin D from This is in part due to the government recommen-
levels much functioning. It is their position that cod liver oil dations, which are FAR too low to offer any health
higher than is still a highly recommended supplement. benefits; the recommended daily dosage being

those found Dr. Mercola is no longer a member of the no more than 200 to 600 IU, depending on age.
in traditional Weston A. Price Foundation honorary board. Meanwhile, researchers have since established
Research does indeed indicate that vitamin D that the therapeutic dosage is anywhere between
diets—in can only effectively target genes when its partner 2,000 to 10,000 IU per day, depending on your
order to bring receptor is activated by vitamin A. weight and other factors, such as skin color and
level of regular sun exposure. (Some people may
After reviewing the evidence, I am person-
serum vitamin ally convinced that there is sufficient vitamin A in require, and can safely take, as much as 20,000
D levels into the current American diet to facilitate sufficient IU daily.)
the normal vitamin D activation. This does not appear to be A dose of 1000 IU vitamin D daily is ade-
the case in third world countries, where cod liver quate to avoid problems with vitamin A in adults.
range? oil, or some other preformed retinol supplement, If the ratio of A to D in cod liver oil is 10 to 1,
40 Wise Traditions SPRING 2009