Diagnosing the cause of stone formation is complex. 

It requires a large range of investigations starting from a simple urine examination to 24 hour urinary excretion of calcium, oxalate and uric acid to chemical analysis of the stone itself. 

Depending on the type and cause of stone formation, the physician recommends measures to reduce further risk of stone formation. But generally Patients having oxalate stones should reduce intake of oxalate containing diet such as spinach, nuts, chocolates and tea. 

They should also avoid vitamin C. Dietary calcium combines with the oxalate present in the intestine rendering it unabsorbable. So oxalate stone formers are advised not to reduce their calcium intake. 

In calcium stone formers, not only high calcium diet such as dairy products should be reduced but also drugs which raise the blood level of calcium like antacids and vitamin D should also be stopped. If there is any sign of an enlarged parathyroid gland causing high level of blood calcium, then it should be treated accordingly. 

Reduction in meat is helpful in all types of stone formers but especially indicated when the stone is made of uric acid crystals. 

Increased water intake to avoid over saturation of the urine with stone forming substances. Low salt intake prevents excessive loss of calcium in the urine. Hence stone formers are advised to take a low salt diet.