Unfortunately the article makes no mention of ascorbate's capability of dissolving calcium oxalate, the material from which most kidney stones are comprised, to almost the same degree as citrate is so capable. Renal function is complex, and I might as well add my conjecture that repeated short-term periods of lactic acidosis are more responsible for stones than ascorbate. Plus also factor in that some people are SF's and some aren't, for reasons still not known, and things get real tough to define and apply to entire populations.