- Objective: To study the prevalence of Helicobacter pylori infection in a representative group of the adult population of central Israel and to evaluate factors which might affect its distribution. Design: Serum specimens were obtained from 311 individuals aged between 20–70 years undergoing periodic health examination initiated by several employers. We randomly selected about 30 subjects of each gender for each decade of age. Subjects answered a standardized questionnaire. A specific, second generation enzyme immunoassay was used to determine the presence of anti-H. pylori immunoglobulin G. Results: The seroprevalence of H. pylori in the overall population was 65%; it increased with age from 43% in those aged between 20–30 years to more than 80% in those aged 60% years and older (P < 0.001). H. pylori infection was not associated with gastrointestinal symptoms, origin, occupation or coffee and tea consumption. The relative risk for H. pylori infection was increased in women smokers. Conclusions: Seroprevalence of H. pylori increased with age and was unrelated to the presence of gastrointestinal symptoms. © Lippincott-Raven Publishers.