The prevalence of Helicobacter pylori infection is exceptionally low among the Malays in the north-eastern region of Peninsular Malaysia. The reasons are unknown. Our aim was to compare environmental factors that differed in relation to H. pylori prevalence among Malays born and residing in Kelantan. A case-control study was conducted among Malays in Kelantan who underwent upper endoscopy between 2000 and 2008. Helicobacter pylori status was determined by gastric histology. Sociocultural and dietary factors were assessed using a validated investigator-directed questionnaire administered after 2008, and the data were analyzed using logistic regression analysis. The study group consisted of 161 subjects (79 H. pylori positive and 82 controls). Univariable analysis identified five poor sanitary practices associated with an increased prevalence of H. pylori infection: use of well water, use of pit latrine, less frequent boiling of drinking water, and infrequent hand wash practice after toilet use and before meals. Multivariable logistic regression analysis identified three variables inversely associated with H. pylori infection: frequent consumption of tea (OR: 0.023, 95% CI: 0.01-0.07), frequent use of "budu" or local anchovy sauce (OR: 0.09, 95% CI: 0.1-0.7), and frequent use of "pegaga" or centenella asiatica (OR: 0.25, 95% CI: 0.1-0.65). Under the assumption that sanitary, sociocultural, and dietary habits have not changed over the years, we can conclude that an increased risk of H. pylori was associated with unsanitary practices whereas protection was associated with consumption of tea and locally produced foods, "pegaga" and "budu." These dietary factors are candidates for future study on the effects on H. pylori transmission. © 2011 Blackwell Publishing Ltd.