Oxalates are naturally occurring compounds in a variety of foods that act as organic acids in plant and animal organisms. The connection between oxalate and kidney stones stems from research which shows the connection between high levels of calcium oxalates in the urine of individuals who develop kidney stones. According to nutritional research, dietary oxalate contributes only around 10 percent of total kidney stone formation, making the recommendations to limit oxalate-containing foods a controversial subject. The effect of oxalate and kidney stones should not be a primary concern for most healthy individuals, as restricting or even eliminating foods that contain oxalates may result in a less nutritious diet.
The compound called oxalate occurs naturally as an organic acid in many foods, such as raw spinach, cocoa and tea. Most research that links oxalate and kidney stones comes from the analysis of oxalate levels in the urine of those who develop kidney stones. Many connections have been made between the compound oxalate and kidney stones, yet most researchers are unsure as to whether dietary oxalates are the main causes behind kidney stone formation. As only a small percentage of dietary oxalate contributes to the overall oxalate levels in the urine, most researchers and nutrition advocacy groups recommend individuals not restrict their intake of foods that contain oxalates.
Many healthy foods are linked to both oxalate and kidney stones, yet eliminating these foods from the diet can result in nutritional loss. Cocoa and tea, for example, contain oxalates but are very high in antioxidants, compounds that fight free radicals. Spinach is another oxalate-containing food, contributing a wide range of vitamins, minerals and other nutrients in the diet in just one serving.
It was previously thought that cooking foods with oxalates could destroy their negative health effects, but more conclusive research has proved exactly the opposite. In fact, overcooking foods high in oxalates destroys many of the valuable nutrients contained within the food, leading to a nutrient-depleted diet. Most healthy individuals can safely consume raw foods containing oxalates and not have a problem, however this depends on an individual's health history and physiology. The research does point out that one can prevent oxalates from contributing to kidney stone formation by consuming healthy amounts of protein and water in the diet.
