Poor Absorption of Calcium and Magnesium

I was told that Magnesium Citrate is the one to go for. I tried Peter Gillham's Natural CALM. It supposes to be pH balanced and would dissolve nicely. It doesn't dissolve completely even with hot water. I'm not sure if I got a bad batch or that's just the way it is.

My blood test reveals that I have low Calcium and low Magnesium, while my hair analysis indicates a high level of both minerals. Obviously, I have very poor absorption of them, I can only absorb very little, the rest are dumped to my hair. So, I'm somewhat hesitant to take either minerals. I suppose unlike Ca, Mg is one of those minerals that you can't OD on. Excess will always be elimnated thru the bowel or hair(?)

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