What can cause Vitamin D toxicity, like not being able to process it?

Answer 1

The problem is fat solubility. It's more difficult for the body to rid itself of excess. Higher than necessary amounts of water soluble vitamins - like Vitamin C and the B vitamins - are simply excreted in the urine. Fat soluble vitamins like A, D and E persist in fatty tissues.
MD answer

Added note - - "Angelic's" article is interesting but it is referring to moderate excess of vitamin D.
(Quote below from article)

"Throughout my preparation of this review, I was amazed at the lack of evidence supporting statements about the toxicity of moderate doses of vitamin D."

You can't take huge excesses of Vitamin D supplements over prolonged periods safely - while you can take "LInus Pauling" type high doses of Vitamin C because the excess ascorbic acid is easily excreted by normal kidney function.

Answer 2

that vit d helps reabsorbtion and absorbtion of ca and increases the ca deposition in bony tissues

Answer 3

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