Vitamin C for Sensitive Stomachs Dietary Supplement Non-GMO Vitamin C, or ascorbic acid, is a white, crystalline, water-soluble substance found in citrus fruits. As an antioxidant, vitamin C scavenges free radicals in the body and protects tissues from oxidative stress. Vitamin C also promotes the absorption of iron, while preventing its oxidation. Vitamin C is a vital cofactor to the formation of collagen, the connective tissue that supports arterial walls, skin, bones, and teeth. A major immune-supporting activity of vitamin C is boosting glutathione levels in human lymphocytes, cells that make up about 25% of all white cells in the blood. More vitamin C is contained in the adrenal glands than any other organ in the body and is required at higher levels during times of stress. Physical stresses on the body such as ingestion of heavy metals, cigarette smoking, immune impairment, extreme temperatures, and chronic use of certain medications such as aspirin also signal the need for increased intake of vitamin C. Vitamin C Powder contains four buffering minerals, in addition to ascorbic acid. When mixed with water, this product produces a reduced-acid solution that is non-irritating to the stomach and intestinal lining. The minerals also make it a more pleasant-tasting and healthful drink. The substances used in this product make it effervesce for a short while when it is mixed with water.