No link between vitamin C and ulcer-bug infection was seen in non-whites.
The findings come from data collected in 1988-1994 from 6,746 U.S. adults. Joel A. Simon, MD, MPH, of the San Francisco VA Medical Center and colleagues looked at the link between blood levels of vitamin C and infection with Helicobacter pylori. Long-lasting H. pylori infection puts a person at high risk of peptic ulcers and gastric cancer.
One in three people showed signs of previous infection with the ulcer bug. Among white people, as vitamin C levels went up, the risk of H. pylori infection went down. The findings appear in the August 1 issue of the Journal of the American College of Nutrition.
It's not clear whether vitamin C protects against ulcer-bug infection -- or whether the infection makes a person's vitamin C levels drop. But Simon says it's a good idea to take more vitamin C if you test positive for H. pylori. A simple blood test shows whether a person is infected. Infection can be cured with the right antibiotics.
"The bottom line is that higher levels of vitamin C may have the potential to prevent peptic ulcers and stomach cancer," Simon says in a news release.
Also not clear is why the findings don't apply to non-whites. Most of the people in the study were white, so it's possible that the study simply couldn't detect a link in non-whites. But there's also evidence that non-whites have lower levels of vitamin C in their stomachs than whites.