In Japan, high prevalences of H. pylori infection and AG are found, which seem to be causes for the high incidence of gastric cancer. H. pylori infection is not a sole cause of gastric cancer, however. Environmental factors, including a diet high in salt, also might be involved. For accurate diagnosis of H. pylori infection and AG, it is important to determine the locations from which the biopsy specimens are taken. Comparison of the severity of AG between different countries should be made using the same biopsy sampling system and grading criteria. Bayerdöerffer et al showed antral predominance of H. pylori colonization, but Genta et al reported more even distribution in the stomach. The authors' patients with NAG and those with antral and mild AG had similar scores of density at the six biopsy sites, whereas those with more extensive AG had the highest score at the middle body on the greater curvature. If only one biopsy specimen should be taken for the diagnosis of H. pylori infection in patients with extensive AG, the middle body of the greater curvature (site 6) would be the most suitable site. Western researchers reported that the grade of chronic and acute inflammation was significantly lower in the body than in the antrum. The authors' findings of patients with NAG were similar to those of Western researchers, but those with atrophy were not. Grades of inflammation and activity in the antrum decrease with the extension of AG. In the authors' patients, the earliest finding of the development of atrophy was found at site 1, and this was the most predominant site of atrophy in patients with extensive AG. Extension of AG into the body was determined by the finding of a biopsy specimen taken at site 3. The earliest finding of the development of intestinal metaplasia was found mostly at the middle body of the lesser curvature and next at the incisura angularis. In patients with extensive intestinal metaplasia, the scores of intestinal metaplasia at site 1 and site 3 were as high as the score at site 2. Site 6 was the last place for the invasion from the extension of AG. If biopsy specimens are taken from site 1, site 3, and site 6, they are enough for the assessment of the extent of AG and intestinal metaplasia. The Updated Sydney System recommended five biopsy sites including the incisura angularis, and its usefulness was coincidentally supported in Japan with a high prevalence of AG seen in results.