One of vitamin C’s primary roles in the body is as an antioxidant, helping to protect cells from oxidative stress. Research published in Free Radical Research (1995; 22(2):131–143) found that patients with inflammatory bowel disease—specifically Crohn’s disease and ulcerative colitis—have significantly reduced levels of vitamin C in the intestinal lining.
Patients with Crohn’s disease were found to have vitamin C levels approximately 35 percent below normal, while patients with ulcerative colitis had levels that were 73 percent below normal. The researchers concluded that much of this loss was due to oxidative stress generated by inflammatory cells. Reduced vitamin C levels, in turn, leave the intestinal lining more vulnerable to further oxidative damage.
Additional research published in the Journal of Manipulative and Physiologic Therapeutics (1999; 22(8):530–533) examined the effects of vitamin C supplementation in students aged 18 to 32 who were experiencing respiratory infections. The treatment group, consisting of 252 students, received 1,000 mg of vitamin C during the first six hours of illness, followed by 1,000 mg three times daily thereafter. A control group of 432 students received decongestants and pain relievers.
Reported cold and flu symptoms in the vitamin C group decreased by 85 percent, while no comparable improvement was observed in the control group. The authors concluded that vitamin C supplementation was effective in relieving symptoms of respiratory infections.
Research appearing in the Archives of Internal Medicine (July 28, 2008; 168(14):1493–1499) also found that higher serum vitamin C levels were associated with a lower incidence of type 2 diabetes. The study included more than 21,000 non-diabetic participants.
Finally, a study published in BMC Gastroenterology (2009; 9(1):74) examined vitamin C supplementation and gallstone formation. In this observational study of 2,129 subjects aged 18 to 65, vitamin C supplementation was associated with a reduced risk of developing gallstones.
