A low oxalate diet may be recommended to prevent kidney stones from forming. Oxalates are chemicals found in plant-based foods. These may collect in the kidney, forming a crystal known as a kidney stone. A low oxalate diet eliminates foods with a high concentration of oxalates; following this diet may help to treat or prevent kidney stones. This diet is usually defined as limiting oxalates to 40-50mg each day.
Oxalate is found in relatively high quantities in plants, particularly spinach, beets, rhubarb, strawberries and other berries, nuts, parsley, and pepper. Another source of oxalate is breads, cereals, wheat germ, wheat bran, and whole-wheat flour. It is also found in chocolate, tea, coffee, cola, and other foods derived from plants.
Some foods may have as much as 10mg of oxalate in a half-cup serving. Meanwhile, low oxalate foods have less than 2mg per serving. Consult with your doctor or nutritionist to determine which foods should be avoided because of their oxalate level. Your doctor may provide you with a list of low-, moderate-, and high-oxalate foods. Some people following this diet can consume high oxalate foods in moderation, but should flush the oxalates from their body by drinking plenty of water.
Eliminating high-oxalate foods means removing many fruits and vegetables from the diet. As a result, those following a low oxalate diet may need to make other dietary changes to compensate for the loss of certain other nutrients that the eliminated foods normally supply. A low oxalate diet should not be started without consultation with your doctor, a dietitian, or a nutrionist.