The recommendation to avoid calcium restriction and consume adequate calcium was previously addressed in Statement 12. The basis for this recommendation is the effect of calcium restriction on enhancing intestinal oxalate absorption. Dietary calcium binds with oxalate in the intestine, forming a calcium oxalate complex that is excreted in the stool.160 When dietary calcium is restricted or not consumed with meals, particularly in the setting of oxalate-rich foods, calcium oxalate complex formation is reduced, leading to an increase in intraluminal oxalate, enhanced intestinal oxalate absorption, and higher urinary oxalate excretion. To address hyperoxaluria, patients should be counseled to consume calcium-rich foods and beverages at meals, which reduces the bioavailability of dietary oxalate. When oxalate bioavailability is reduced, intestinal oxalate absorption and urinary oxalate excretion will decline. High-quality reviews of clinical and metabolic studies have shown that increasing dietary calcium if low and pairing its consumption with meals dramatically reduces urinary oxalate, even when oxalate intake is very high, by increasing intestinal binding and reducing absorption.161, 162 The amount of calcium needed to bind dietary oxalate during meals varies with oxalate content and other components of the meal, digestive tract motility and permeability, and other individual factors. Of note, however, increasing calcium intake beyond that needed to bind oxalate in the digestive tract will increase intestinal calcium absorption and urinary calcium excretion, potentially increasing stone risk. Consequently, mitigating high oxalate intake with very high calcium intake may not be advisable in all cases. While many oxalate-rich foods have a number of health benefits (e.g., nuts, spinach, beets, beans, avocados, potatoes), excessive intake of oxalate-rich foods should be avoided. Moderation with regard to oxalate intake and normal calcium intake in most circumstances should reduce hyperoxaluria risk.