Todd,
I just read through a major portion of The Diabetes Solution this past weekend. I remembered seeing something about kidney stones in the book, so I just went and looked it up. I have the March 2007 edition, and in the middle of page 180, Bernstein recommends calcium citrate as he says it is well absorbed in the gut and inhibits the formation of kidney stones. Hope this helps and so sorry that you have been having issues.
Gail