Helicobacter pylori infection has accompanied man for thousands of years. In some infected patients, a complex and dynamic pathogen-host reaction triggers pathogenic pathways resulting in development, inter alia, of atrophic gastritis, peptic ulcer disease (both gastric and duodenal), gastric adenocarcinoma, and MALT lymphoma. Large-scale eradication therapy is associated with a rapid increase in antibiotic resistance, gut flora composition disturbances, and increased risk of development, inter alia, of paediatric infectious diarrhoeas, atopic diseases, and oesophageal adenocarcinoma. Our diet contains many substances with potent antibacterial activity against H. pylori. Dietary interventions enable a decrease in H. pylori colonisation and result in a decrease in gastritis prevalence, thus potentially lowering the risk of gastric adenocarcinoma development.