For example, H. pylori might be transmitted when kids forget to wash their hands after they go to the bathroom, then put their hands in their mouths, says John Kurata, Ph.D., associate adjunct professor at the University of California at Los Angeles and director of research and policy analysis for the San Bernardino Medical Center. The bacteria bore through the protective gel lining the digestive tract and settle in the stomach or duodenum. In most people they simply cause a minor inflammation that no one ever notices, says Dr. Kurata. In others they cause an ulcer. It's likely that one woman has a stomach or duodenum that is genetically predisposed to produce more acid than normal or is regularly exposed to a major irritant like smoke or alcohol, says Dr. Kurata.
Studies indicate that smokers are twice as likely as nonsmokers to develop an ulcer.
The tobacco simultaneously impairs the digestive system's protective gel and stimulates acid secretion. And solutions of 80-proof alcohol applied directly to the protective gel in the stomach and duodenum have been shown to cause bleeding and ulceration. The effects of lower concentrations of alcohol found in beer and wine have not been studied carefully. Here's how you can fight off an ulcer that's caused by bacteria. See your doctor.