[Bruce:] All your social hormones are controlled
by vitamin D. You don't get enough...and vitamin
D is a special one because that goes to a
hormone.
It's really more a hormone than a vitamin.
But it's a steroid hormone, just like estrogen.
And the nice thing about these steroid hormones
is they bind to a receptor, which goes to
the DNA and recognizes 12 bases in the DNA,
the 6 bases, 3 base spacer, and then another
6 bases.
And what that does is that's the telltale
signature of estrogen or vitamin D hormone.
So it's a steroid hormone, and it's controlling
a thousand genes, lots of them in your brain.
So if you're vitamin D deficient, you're in
deep trouble.
[Rhonda:] Yeah.
70% of the U.S. population, you know, is 
not getting enough.
[Bruce:] Yeah.
We're playing video games and watching TV,
and we're not out in the sun, and we're in
our car rather than walking.
[Rhonda:] And then there's a problem with
physicians not knowing what...you know, the
RDA right now for vitamin D is 600 IUs, of
international units of vitamin D. That's what
people are required to take, you know, orally
as a supplement.
But the question is, if you're very deficient,
so deficiency is defined as 25-hydroxy vitamin
D levels precursor to the hormone, less than
20 nanograms per mil.
And it takes 1000 IUs a day to raise blood
levels by 5 points, right?
5 nanograms per milliliter.
So if you're very deficient, you're still
not gonna raise yourself up to a sufficient
level, which is considered 30 nanograms per
mil or above.
And I think that there's a lot of difficulty
in terms of, like, what's in the scientific
literature for people to figure out what is
the optimal amount of vitamin D?
How much do we actually need?
And, you know, I think part of that problem
is due to the fact that some of the things
that you've been mentioning, and that is people
are looking at these short-term consequences.
Well, rickets, you know, bone homeostasis.
And that's really what most people and most
doctors are looking at when they're thinking
about how to...
[Bruce:] We don't have rickets anymore.
But we do have rickets.
80 patients at Children's Hospital where I
work came, the kids came in with rickets.
They don't get straight bones.
Well, rickets had been eliminated.
But they were all African-American women,
who were nursing their babies, and they didn't
have any vitamin D. If you used formula, it'd
have a little vitamin D in it.
So it's when we haven't eliminated rickets...though
for a long time, doctors never saw a case
of rickets.
But you don't wanna just look at rickets.
You wanna look at these long-term proteins
that are helping you live longer.
So, and that means changing people's thinking.
And so you look at all of vitamins and minerals,
just one after another, some appreciable percentage
of the population is really deficient.
And nobody seems to care.
[Rhonda:] Right.
And then you get studies coming out, like
the "Annals of Internal Medicine" publishing
papers saying, "Enough is enough.
You shouldn't even take your vitamin and mineral
supplements because not only are they not
doing anything, but they're doing harm."
So...
[Bruce:] Rhonda and I agree that was a horrible
paper, an appalling paper.
Because, see, the docs are all used to randomized,
double-blind clinical trials, which makes
a lot of sense because if you test a drug
in people nobody has it to start with, and
you're treating the whole population.
But applying it mindlessly, nutrition is stupid
because if 90% of the population has enough
of vitamin X and 10% are really deficient,
you wanna test it on that 10%.
Otherwise, you'll never see anything because
you're diluting it with the 90% who has enough.
So you have to measure it.
And then as Rhonda pointed out, if you use
the RDA for vitamin D, you're not gonna get
somebody into the sufficient range.
So what you need to do is measure it before
and measure it afterwards.
And that's not a big deal, but people who
publish papers, who don't do that, just pollute
the literature.
