One of the roles vitamin C has is as an antioxidant, protecting cells from oxidative stress. According to research appearing in Free Radical Research (1995;22(2):131-143), patients with inflammatory bowel disease (Crohn’s disease or ulcerative colitis) have reduced levels of vitamin C in the intestinal lining. Patients with Crohn’s disease have levels that are 35% below normal and patients with ulcerative colitis have levels that are 73% below normal. The researchers state that most of the loss of vitamin C is due to oxidative stress from inflammatory cells. The loss of vitamin C makes the cells lining the intestines more vulnerable to oxidative stress.