Calcium Hormones

[nick]

Also, with a high bone turnover rate, this means that the osteoclast activity is increased but not as much as the osteoblasts because of a surplus of incoming calcium?

[nick]

Study Shows Limited Benefits From Calcium

http://news.yahoo.com/s/ap/20060216/ap_ ... cium_bones

[RRM]

Is the calcitonine level increased, because it stimulates excretion of calcium through the urine? I take it your body also decreases the absorption rate as well?

I cant relate your calcitonine question with the coupling phenomenon.

And related to osteoblast, osteoclasts are still tearing down bone at a faster rate than formation anyways. So it can't be 'protective' against osteoporosis?

Decreasing osteoclast activity cant be protective because the osteoclasts only break down what needs to be cleaned up: old cells that dont work properly anymore.

[RRM]

But with a high calcium intake, that doesn't happen, so the BMD is increased. I would think that the osteoclast activity would decrease, but for new bone to be deposited osteoclasts must break down old bone for the new bone to be deposited?

No, for new cells to be calcified, osteoblasts just need to compose a new matrix upon which calcium may precipitate.

I thought from your osteoporosis page, that redundant calcium is resorbed because there are 'too many bricks in the house' and your body would get rid of it after some period of time. But with a high calcium intake, will that calcium just stay in there longer? Is there a point in time where old bone (calcium) has reached its usefullness? How do the osteoclasts know when to tear down bone?

There are very complex intracellular signalling pathways that tell osteoclasts to break down disfunctioning cells, and to break down cells for releasing redundant calcium.
With a high calcium intake, the breakdown of disfucntioning cells will not be slowed down, but the breakdown to release redundant calcium will be.

Is there a maximum calcium holding rate (highest BMD attainable), where your body can't keep up with excessive calcium? Thus decreasing absorption rates at all costs?

Yes, just as there is regarding muscle volume.

Also, I understand that young people with a low BMD still have perfectly healthy bones. Why don't they get fractures though?

Because their bones are perfectly healthy.
Just as a non-bodybuilder is strong enough to perform all kind of physical activities.

[RRM]

Also, with a high bone turnover rate, this means that the osteoclast activity is increased but not as much as the osteoblasts because of a surplus of incoming calcium?

With a high bone turnover rate osteoblast activity may be more increased than osteoclast rate or the other way around, depending on multiple factors.

[RRM]

Study Shows Limited Benefits From Calcium

http://news.yahoo.com/s/ap/20060216/ap_ ... cium_bones

Thats no news.
Many studies have shown that with declining bone health the harder it is to increase bone mass with extra calcium.

Only in people where there is no problem, you can 'solve the problem' with extra calcium.

[nick]

I have some questions about the Heaney response you gave.

Heaney (30) argues that there is no such thing as higher BMD than required / biologically functional. That all the calcium retained in bone is always required.

Much like a bodybuilder is overly pumped.

Heaney assumes that net calcium absorption rate is more or less fixed at a very low level (about 10% at intakes in the range of current recommendations), and that this proves that our human prehistoric diet was very high in calcium.

So since the calcium absorption rate is low this means that calcium intake is high?
Due to the low absorption rate?
Net calcium absorption rate refers to total daily calcium intake?

So basically if I ingest 500mg of calcium my body will on the average absorb only about 10% of that?

I must think that on the Wai diet, your body changes that since the amount of calcium is lower so the absorption rate is increased to insure sufficient levels? Hence the studies you cite about the Chinese and the young girls.

Heaney speculates that "with advancing age, ability to adapt to low calcium intake largely disappears", while however this low absorption rate is a necessity if excessive calcium can no longer sufficiently be temporarily stored in bone, due to a decrease in osteoblast capacity to form new matrix upon which all this calcium can precipitate (subject to the coupling phenomenon).

"with advancing age, ability to adapt to low calcium intake largely disappears"

This means that the ability to adapt from a low calcium intake to a higher one disappears?
This sentence is kinda of ambiguous but you make the distinction after it.

Heaney also assumes that excess calcium "cannot be stored"; is never temporarily stored in our bones, and is always immediately excreted. That bone metabolism and the system that safeguards serum calcium level are only coupled regarding maintaining serum calcium levels sufficiently high, but not to prevent it from increasing too much.

I think I understand most of this but what do you mean by coupled in terms of the "safegaurd system"?

When calcium intake is very high, calcium excretion cannot keep up (Heaney: "urine calcium is in itself only weakly regulated"), and the extra calcium is temporarily 'stored' in the bones, until serum calcium levels have sufficiently decreased, and this extra calcium can be gradually excreted.

So the body can't just take calcium and increase its' excretion of calcium into the urine instead of storing it in the bones?
It has to store it in the bones when intake level it high?
Is that the system works then?

I love reading through your responses to those 'questioning' scientists.
It is amazing to see you how answer their questions in such a clear and logical response.
You appear to have all your bases covered and then some!

[RRM]

Heaney assumes that net calcium absorption rate is more or less fixed at a very low level (about 10% at intakes in the range of current recommendations), and that this proves that our human prehistoric diet was very high in calcium.

So since the calcium absorption rate is low this means that calcium intake is high?

Yes.

Due to the low absorption rate?

No. If little calcium is absorbed from the food consumed, this will not stimulate you to consume more calcium (calcium rich foods).

Net calcium absorption rate refers to total daily calcium intake?

No, to the percentage of the calcium absorbed into the blood relative to the total amount ingested (by consuming foods).
Calcium intake influences calcium absorption rate, but not the other way around.

So basically if I ingest 500mg of calcium my body will on the average absorb only about 10% of that?

No, your body will absorb (into the blood) about 200 mg, regardless of the (moderate) amount consumed: 67% of 300 mg; 40% of 500mg; 25% of 800 mg etc.

on the Wai diet, your body changes that since the amount of calcium is lower so the absorption rate is increased to insure sufficient levels? Hence the studies you cite about the Chinese and the young girls.

Indeed.

Heaney speculates that "with advancing age, ability to adapt to low calcium intake largely disappears", while however this low absorption rate is a necessity if excessive calcium can no longer sufficiently be temporarily stored in bone, due to a decrease in osteoblast capacity to form new matrix upon which all this calcium can precipitate (subject to the coupling phenomenon).

"with advancing age, ability to adapt to low calcium intake largely disappears"

This means that the ability to adapt from a low calcium intake to a higher one disappears?

'Adapt' may not be the right word ("cope" may be better), but yes, with age the capacity to temporarily store excess calcium decreases, and thus the body has to decrease the absorption rate.

Heaney also assumes that excess calcium "cannot be stored"; is never temporarily stored in our bones, and is always immediately excreted. That bone metabolism and the system that safeguards serum calcium level are only coupled regarding maintaining serum calcium levels sufficiently high, but not to prevent it from increasing too much.

I think I understand most of this but what do you mean by coupled in terms of the "safegaurd system"?

The coupling of osteoblast and osteoclast activities so that the blood calcium level is kept at adequate level.

So the body can't just take calcium and increase its' excretion of calcium into the urine instead of storing it in the bones?

It can, because eventually all that extra calcium is excreted, but not as fast as it is taken up, hence the need to store it somewhere in the meantime.

It has to store it in the bones when intake level it high?

Yes, to safequard the blood calcium level.

I love reading through your responses to those 'questioning' scientists.
It is amazing to see you how answer their questions in such a clear and logical response.

Thank you! Thats my goal, as I believe that there must be clear logic in it if it is to be correct.

[nick]

No. If little calcium is absorbed from the food consumed, this will not stimulate you to consume more calcium (calcium rich foods).

So when you eat low calcium rich foods, the absorption rate will increase.
It won't have an effect of making your body want to eat more calcium rich foods. That makes sense as probably getting enough calcium was never a concern with it comes with diet.

No, to the percentage of the calcium absorbed into the blood relative to the total amount ingested (by consuming foods).
Calcium intake influences calcium absorption rate, but not the other way around.

Ok. So basically with every meal that you eat, your body will take up 200mg of calcium if the meal contains 200mg or more.
So what is an ideal calcium daily allowance/range?
Anywhere from 200 to 1000 mg?

This also makes me think that since your blood can only take up 200mg with moderate intakes, that there is no 'master' control that limits how much total calcium you ingest throughout the day?
If this is what makes it possible to ingest more than biologically needed, then that makes so much sense!

No, your body will absorb (into the blood) about 200 mg, regardless of the (moderate) amount consumed: 67% of 300 mg; 40% of 500mg; 25% of 800 mg etc.

How is the body unable to decrease absorption rate with high/excessive amounts consumed?

Or is the reason for higher intake associated with high calcium intake throughout the day with ones meals?

It can, because eventually all that extra calcium is excreted, but not as fast as it is taken up, hence the need to store it somewhere in the meantime.

So it can't just go straight from the intestines to the urine?
There is a protocol to follow, which includes being taken up into the blood.

If I ingest 100mg of calcium from a meal, will that only be taken up into the blood and stay only in the blood?
Does that depend upon the calcium-blood level?

Thank you! Thats my goal, as I believe that there must be clear logic in it if it is to be correct.

Do you find it hard to come up with ways to describe complex biochemistry interactions?

[nick]

I'm having a discussion about your theory with someone from a nutrition discussion board.

He is very adamant about raw diary being different than pastuerized, homogenized, fortified and other adulterations. He says that because of these adulterations this may change the milk whereas raw milk would be different in regards to calcium intake or absorption rates.

Here is what he says in regards to your theory:

> Fact 1: Osteoporosis may be the result of premature exhaustion of the capacity
> to form new bone matrix.

Saying it "may be the result" is not a fact, but a theory. And this is
the fundamental weakness in Wai's theory. She needs to prove that the
osteoblasts are exhausted, that raw milk has the same effects on bones
as pasteurized, that all calcium sources are equal. I'll save her some
trouble. All calcium sources are NOT equal. The absoption rate varies
greatly based on the food type and preparation.

> Fact 3: Like all other cells in our body, osteoblasts are subject to aging
phenomena

Aging phenomena are reduced through intermittent fasting and/or calorie
restriction, as numerous animal and human models show.

http://www.calorierestriction.org/
http://www.life-enhancement.com/article ... asp?ID=851

> Fact 4: High bone turnover rates accelerate osteoblast replication rates.

It has not been shown that high calcium intake exhausts osteoblasts
or increases bone turn over. All of this is simply assumed by Wai.
All sources of calcium are unique. You can't judge calcium based on
modern diets where milk is typically pasteurized, homogenized, low
fat, fortified, and otherwise adulterated.

> Fact 5: In healthy young people (not in elderly), maintaining high BMD comes
with high
> bone turnover rates.

That fact is also questionable. I'm sure we can find some exceptions
in Eskimos, African tribes, and others eating high calcium.

> Fact 6: The key to osteoporosis prevention may lay in the lifetime prevention
of high bone
> turnover rates (accomplished by low calcium intakes in healthy young people).

Again, saying the key to prevention "may lay" in low calcium intake
is a theory - not a fact. The theory is based on flawed data, like
statistics from people eating processed dairy. The statistics would
probably become meaningless when dealing with raw dairy, and maybe
full-fat dairy in general. We must consider each type of dairy, and
not paint all dairy with the same flawed brush.


He also thinks that you haven't taken into account the many other factors too.
Did you ever find a correlation with exercise and hip fracture rates?
I would think that exercise wouldn't be strong enough of an influence as calcium.
What about amenorhea?
Is that too weak of an influence, or is it too short term whereas calcium has a more long-term influence?
That would make sense to me, but this poster thinks you haven't taken into account the other possibilities.
Just curious if he may have a point.

[avalon]

I confess to being calcium illiterate and still find this all very fascinating! Makes me want to learn more...so, I have a small off the cuff question

Is excess calcium excreted, or does it collect in other areas of the body, unltimately causing problems? Because of this thread I was looking up calcium supplements, and this was mentioned. Is this only related to supplements? Meaning- pills/powder???

p.s.
I wish I could get my hands on some raw milk. But with travel and cost It's easier to get raw cheese so I do eat a minimal amount every so often.

[Wintran]

Here's a comment to the guy you quoted, nick.

You can't judge calcium based on
modern diets where milk is typically pasteurized, homogenized, low
fat, fortified, and otherwise adulterated.

Not entirely, just as you can't judge cholesterol based only on the heated type of oxycholesterol provided by cooked food. However, the majority of people today get their excessive calcium intake through pasteurized milk products, so there is reason to focus on this type of calcium and the bad side-effects that it may lead to, because it can explain a lot of common health issues.

[nick]

Yes!

I realized that too when I was explaining to him that on the average dairy products contain more calcium than the other food groups.

http://www.4.waisays.com/prehist-calc.htm

Not to mention that fortified milk will have more calcium, but in general dairy still has more.
He thinks that RRM is trying to give raw milk a bad rap or something or that calcium from raw milk will 'somehow' be absorbed to a lesser degree than pasteurized, fortified, homogenized milk.

[nick]

I confess to being calcium illiterate and still find this all very fascinating! Makes me want to learn more...so, I have a small off the cuff question

Just a note, at the top of the calcium theory page, there is a link to a summary of the theory which I found helpful when first learning about.
There is so much info that I would forget about the basic stuff.

Is excess calcium excreted, or does it collect in other areas of the body, unltimately causing problems?

In this study:
http://content.nejm.org/cgi/content/abstract/354/7/669

They found that with high calcium supplementation came with an increase in kidney stones.

Also, they supplemented with Vit. D, which increases intestinal calcium absorption, which then increases blood-calcium levels.

From the Excessive Calcium page:

However, since supplementary vitamin D / calcitriol increases the blood-calcium level (45), this extra calcium can precipitate in arteries and on the outside of the bones, causing arteriosclerosis and bone-deformities (46). It can also settle in joints and ligaments, and can cause muscle-cramps because the blood-calcium level needs to be low enough to deport calcium from muscle cells. It can even kill muscles cells (if the calcium cannot be deported), eventually causing fibromyalgia.

Because of this thread I was looking up calcium supplements, and this was mentioned. Is this only related to supplements? Meaning- pills/powder???

Supplements are more dangerous because they are so concentrated.
But in those countries that much dairy, whatever amount that would be, it does have an effect.

p.s.
I wish I could get my hands on some raw milk. But with travel and cost It's easier to get raw cheese so I do eat a minimal amount every so often.

I don't think a little now and then is excessive at all, so in regards to osteoporosis I think it would be harmless.
But I'll let RRM give his opinion.

[avalon]

Thanx for the info, nick!