On Sun, 7 Jan 2001 17:25:19 -0500, Philip Thrift <[log in to unmask]>
wrote:

>Cordain discusses this
>
>  http://www.lifeservices.com/cordain.html  and other places
>
>... some of Cordaines points...


>Lastly, and most importantly, the critical dietary factor influencing bone
>metabolism and hence osteoporosis is not calcium
>intake, nor calcium excretion, but rather calcium balance...

And calcium balance is achieved by a proper mixture of acid loading and
alkaline loading food.

From above:<<Foods which cause a net acid excretion include meat, fish,
cheeses and grains. Fruits and vegetables have a net alkaline val
ue and
consequently reduce acid excretion and hence reduce calciuria thereby
halting bone resorption and actually allowing bone accretion to occur.

Although the dietary calcium to protein ration in stone age diets would
have been quite low, the large amount of fruits and vegetables (35% of
total energy) included in the diet would have produced a net dietary acid-
base status which would have favored bone accretion even in the face of
enormous protein intakes.>>

So, what you forgot to mention was "the large amount of fruits and
vegetables included in the diet".
Even in ice age europe in springtime very much green herbs emerged.
E.g. rumex, which is high in calcium.
The summers could have equaled out what the winters discarded of bone.
And after these people didn't grew verz old-- how could they have
experienced osteoporosis as today.

How can exercise contribute to bone mass?
Not exe
rcise, but load (weight) on the bone.
The bone has sensors, which diret it to grow if used and in places where
necessary. And likewise to build down , where not used.
What builds up/down bone is called the osteoplasts/osteoclasts.

Amadeus
(who had a multiple broken bone lately)