It could be the way your body is utilizing the calcium, might be a lot flowing around the system, but not as much being used. Magnesium is always critical to Calcium absorption.
There's many things out there stating you need 1 magnesium for every 2 calcium, but more recent information seems to say the opposite that for proper calcium absorption you need 2 magnesium for every 1 calcium in the diet.
I use the Calms formula sometimes which is already 2-1 mag/cal but I'm realizing that the dosage I've been taking off and on up until now has been about half of what a normal person needs. On top of this I take additional magnesium with malic acid to break up liver stones for Liver Flushes so my magnesium levels are probably throwing this magnesium/calcium balance way off.
The vitamin C aspect though I find very fascinating as I used to use a buffered Vitamin C powder with about 25-30% calcium content to buffer the vitamin C and I was perfectly fine with that (it was probably my main source of calcium too). Then suddenly I switch to pure ascorbic acid and now after about 2 months on it I can't tolerate it anymore without it triggering panic attack like symptoms.
That's a good point Formales, I always wonder with the adrenals sitting right on top of them in the body as well, that people suffering from adrenal fatigue maybe have a originating problem with Kidney function. Perhaps it has something to do with mineral regulation in the Kidneys? Or a lack of mineral balance to begin with.