Helicobacter pylori is recognized as a major cause of gastric cancer, gastritis, and peptic ulcer disease in adults and is thought to be acquired in childhood. Adults who were breastfed in infancy were less likely to be seropositive for Helicobacter pylori than others not breastfed.
Fall, C.H.D. et al, Growth in infancy, infant feeding, childhood living conditions, & Helicobacter pylori Infection at age 70. Arch Dis Child 1997; 77(4); 310-14.