Optimal C 1000 supplies Vitamin C (as calcium and magnesium ascorbates), along with calcium and magnesium as mineral ascorbates, in addition to citrus bioflavonoids (citrus fruit), Superoxide Dismutase (from vegetable culture), and Catalase (from vegetable culture). At higher dosages mixed ascorbates are less likely to cause digestive distress as compared to ascorbic acid. Use wherever the need for vitamin C is determined.