Eat less sodium
According to the Urology Care Foundation, too much salt in the urine prevents calcium from being reabsorbed from the urine to the blood. This causes high urine calcium, which may lead to kidney stones. Try to eat less salt.
Eat fewer oxalate-rich foods
Some kidney stones are made of oxalate, a natural compound found in foods that binds with calcium in the urine to form kidney stones. Limiting oxalate-rich foods may help prevent the stones from forming. Foods that are high in oxalates are spinach, sweet potatoes, chocolate, beets, coffee, peanuts and rhubarb.
