Does dietary vitamin C cause oxalate stones to form?
Most likely it does not. While it is true that ascorbic acid, along with ethanolamine and the amino acid glycine, can be degraded to oxalic acid (oxalate), the dietary conversion to oxalate plays a minor role in the overall oxalate production in the body. Most oxalate is eliminated through excretion in urine rather than being metabolized further as an energy substrate. Formation of calcium oxalate stones occurs as a result of excessive production of oxalate, excessive calcium elimination, and super-saturated urine. Thus, even a large dose of vitamin C would not lead to an appreciable increase in the calcium oxalate production.
