Here is what I have learned about kidney stones:
Reducing formation involves keeping calcium and oxalate dissolved in the urine. Reducing the amount of calcium in the diet generally does not help, but can actually make matters worse. The body compensates by drawing calcium from the bones and dumping it into the urine.
A high protein diet does significantly increase recurrence (Am J Epidemiol 96: 144(1):25-33).
Drink 2 liters of lemonade per day, made from 4 ounces of reconstituted lemon juice (not lemons), and sweetened with stevia, not sugar. (J Urol 96; 156:907-909). This keeps calcium in solution and reduces oxalate levels.
Take 200-400 mg of magnesium and 100 mg of B6 per day with meals, which can reduce recurrence by a factor of 10 (J Urol 74; 112:509-512).
Add 10 grams of rice bran/ day to the diet, which can reduce recurrance rate by 78% (BR J Urol 86; 58(6):592-595).
Cut back on caffeine and sugar (no coffee, tea or colas).
Stop drinking colas or anything high in phosphoric acid.
Reduce consumption of high-oxalate foods: chard, rhubarb, beets, parsley, cocoa and tea. Herbal tea is OK.
I hope this helps.