A team from the Western Infirmary, Glasgow, Scotland, assessed whether the reduction in intragastric vitamin C concentration caused by Helicobacter pylori infection results in reduced bioavailability of the ingested vitamin.
1,106 randomly recruited subjects were included in the study. H. pylori status was determined by measurement of serum IgG antibody titres to H. pylori, using a validated ELISA. Dietary vitamin C intake was calculated from a food frequency questionnaire, and plasma vitamin C concentrations were measured using a fluorometric assay.
|H. pylori-positive subjects had a plasma vitamin C concentration 20% less than normal.
|BSG Annual Meeeting 2001 |
Correction was made for potential confounding factors such as age, sex, smoking, and social status.
Researchers found 63% of individuals to be H. pylori seropositive. Of those, mean plasma vitamin C concentration was only 65% of that found in seronegative subjects. After correction for reduced dietary intake of vitamin C and other potential confounding factors, this concentration was found to be 80% of that found in negative subjects.
From their data, researchers M. Woodward and fellow authors found that H. pylori infection substantially impaired the bioavailability of vitamin C. They emphasize that this, together with the reduced vitamin C intake of H. pylori-positive subjects, markedly reduced the plasma vitamin C level of infected subjects.
Woodward concludes on behalf of the group, "The reduced circulating levels of vitamin C in H. pylori infected subjects may contribute to the etiology of gastric cancer, as well as other diseases associated with antioxidant deficiency."