Oxalate is a naturally occurring molecule found in abundance in plants and humans. It's not a required nutrient for people, and too much can lead to kidney stones. However, research indicates that boosting your intake of calcium-rich foods when you eat foods that are high in oxalate may be a better approach than simply eliminating it from the diet. As they digest, oxalate and calcium are more likely to bind together before they get to the kidneys, making it less likely that kidney stones will form. Foods that are high in vitamin C can increase the body's oxalate levels. Vitamin C converts to oxalate. Levels over 1,000 milligrams (mg) per day have been shown to increase oxalate levels. Taking antibiotics, or having a history of digestive disease, can also increase the body's oxalate levels. The good bacteria in the gut help get rid of oxalate, and when the levels of these bacteria are low, higher amounts of oxalate can be absorbed in the body.