Ascorbic acid, or vitamin C, aids in many functions of the body, including the absorption of iron. Large doses of C do not usually cause toxicity because, as a water-soluble vitamin, it is simply excreted in the urine. People who tend to form kidney stones may find their condition aggravated by vitamin C supplementation or megadosing.
Review Date 2/2/2019
Updated by: Emily Wax, RD, CNSC, University of Virginia Health System, Charlottesville, VA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.