Limiting high-oxalate foods and maintaining hydration reduces recurrence of which type of kidney stone?

• A. Urate stones
• B. Calcium oxalate stones
• C. Cystine stones
• D. Struvite stones

Answer: (B)

Limiting foods high in oxalate and staying well hydrated target the most common type of kidney stone, which forms when calcium binds with oxalate in urine. When you eat oxalate-rich foods, urinary oxalate rises and increases the chance that calcium oxalate crystals will form. Drinking plenty of fluids raises urine volume, diluting calcium and oxalate concentrations and reducing their tendency to crystallize. Over time, this lowers the risk of stone formation and recurrence for calcium oxalate stones. Other stone types have different triggers—urine acidity or bacterial infection for uric acid or struvite stones, and a genetic issue with cystine stones—so this specific dietary approach is particularly effective for the calcium oxalate variety.