Oxalate content in common Japanese foods.

The radioenzymatic method was used to determine the oxalate contents in common Japanese foods. High concentrations of oxalate were detected in spinach, Perilla frutescens, pepper, sesame, chocolate, and tea. Beer and coffee also contained some oxalate. Fruit and meat were low in oxalate content. Therefore, among the common Japanese foods, the most important foods to be avoided to restrict oxalate intake are chocolate, tea, and spinach.