Helicobacter pylori infection is associated with low vitamin C levels, according to researchers at the San Francisco VA Medical Center. Helicobacter pylori isthe bacteria that causes peptic ulcers. In a study, published in the August 1, 2003 issue of the Journal of the American College of Nutrition,blood samples were analyzed and data taken from nearly 7,000 subjects. Samples of 32% of the participants tested positive for antibodies to H. pylori. Subjects with the highest blood levels of vitamin C had a 25 % lower chance of infection. It is not certain if the vitamin C levels are low because of the infection, or if the low vitamin C levels are somehow responsible for the infection.