With that being said, I've read that baking soda will also help prevent and disolve existing kidney stones........
Make sure you closely monitor blood pressure if doing that more than once a week or so.
I've tried it; baking soda relieved the heartburn for only 45 seconds or so -- back to the PPI.
Have had a calcium oxalate kidney stone (don't wish one on my worst enemy), but to the best of my knowledge wasn't taking any significant supplemental C.
I just hope that higher dose (1000-2000 IU) D3 doesn't turn up some bad long-term effects.