Avoid spinach, bran, beets, and nuts, among others rich in oxalate
As mentioned previously, eating foods rich in oxalate like spinach, bran, beets, and nuts can significantly increase the concentration of oxalate in urine, according to research guru Cleveland Clinic. If you can, avoid foods like these. Alternatively, eating calcium-rich foods or taking a calcium-supplement can reduce the concentration of oxalate. Because oxalate and calcium have a high chemical affinity for each other, they readily bind together, preventing oxalate crystal formation.