Not all stones are equal. Kidney stones can form different compounds that crystallize and form stones. Knowing which types of kidney stones you are at higher risk for is important so you can make alterations in your diet that will lessen your risk. Stones can be one of four types.
- Calcium stones are by far the most common type of kidney stone. They can form when either calcium oxalate or calcium phosphate bind together in the urine. Calcium oxalate stones are more common, especially after gastric bypass surgery. Calcium oxalate stone formation may be caused by high calcium and high oxalate excretion.
- Uric acid stones form when the urine is especially acidic. A diet rich in animal protein such as meats, fish, and shellfish may increase uric acid in urine. If uric acid becomes concentrated in the urine, it can form a stone by itself or along with calcium.
- Struvite stones result from kidney infections.
- Cystine stones result from a genetic disorder that causes cystine to leak through the kidneys and into the urine.