Duncan Vincent wrote:
The calcium found in water is almost totally unabsorbable by plants(or
humans for that matter). Makes my blood boil every time i see a tums
commercial telling people that it "contains calcium that your body needs".
Calcium nitrate is very readily absorbed and is very cheap.


Really?? I'm surprised that you would say that.
I can't say much about plants and what they can absorb, in the way of
calcium. On the other hand, Tums is calcium carbonate I believe. The
calcium supplement that my physician wants me to take and the same one
my wife's doctor wants her to take uses calcium carbonate as the calcium
source.
I'm aware of the vitamin D connection and humans absorbing and using
calcium and I'm aware that calcium citrate is an alternative as a
calcium supplement. As I understand it, calcium citrate can be absorbed
when taken without food but calcium carbonate should be taken with food
because stomach acid is required to make it absorbable. I suppose people
taking strong acid suppressors would need to keep this in mind.
Sorry to emphasize the off topic half of your comments but if you are
going to convince me that Tums are not useful as a calcium supplement,
I'll need more information before I believe it. (Feel free to prove me
wrong. I like to learn.)

Steve