Can too much calcium cause kidney stones?
Health providers and scientists used to believe that eating less calcium would help reduce the risk of common calcium-oxalate kidney stones (that make up nearly 75% of all kidney stones). Current information indicates just the opposite. A diet adequate in calcium may actually reduce the risk of stone formation. The substance oxalate, which is found in tea, nuts and several fruits and vegetables, is believed to be more influential in kidney stone formation than calcium. Adequate calcium (1000 to 1200 mg per day for adults depending on age) may reduce the risk of stone formation because calcium in the diet combines with oxalates in the intestine, prevents oxalate absorption, and thereby reduces oxalates available to form kidney stones. Experts recommend people who have a history of kidney stones check with their doctor or health provider before modifying their calcium intake or making any dietary changes.
