ascorbic acid /əskôr″bik/ [Gk, a, not; AS, scurf, scurvy] , a water-soluble, white crystalline vitamin present in citrus fruits, tomatoes, berries, potatoes, and fresh green and leafy vegetables, including broccoli, brussels sprouts, collards, turnip greens, parsley, sweet bell peppers, and cabbage. It is essential for the formation of collagen and fibrous tissue for normal intercellular matrices in teeth, bone, cartilage, connective tissue, and skin, and for the structural integrity of capillary walls. It also aids in fighting bacterial infections and interacts with other nutrients. Signs of deficiency are bleeding gums, tendency to bruise, swollen or painful joints, nosebleeds, anemia, lowered resistance to infections, and slow healing of wounds and fractures. Severe deficiency results in scurvy. A large excess of ascorbic acid may cause a burning sensation during urination, diarrhea, skin rash, and nausea and may disturb the absorption and metabolism of cyanocobalamin. Results of tests for glycosuria, uric acid, and iron may be inaccurate when the patient is receiving large amounts of the vitamin. Also called antiscorbutic vitamin, vitamin C. See also ascorbemia, infantile scurvy, scurvy.
