Salt and gastric adenocarcinoma:: A population-based cohort study in Norway

Background: Gastric adenocarcinoma is the second leading cause of cancer death worldwide. It has been suggested that consumption of salted foods is associated with increased risk of this cancer, but the results of the few available prospective studies are contradictory. Methods: A population-based, prospective cohort study in Nord-Trondelag County in Norway during 1984 to 2002 addressed dietary salt intake in relation to risk of gastric adenocarcinoma. In 1984 to 1986, all adult county residents were invited to a health survey in which participants answered questionnaires concerning dietary salt intake and other factors. Gastric adenocarcinomas were identified in the Norwegian Cancer Registry. Relative risks were calculated using Cox proportional hazards regression models, adjusted for potentially confounding factors. Results: Follow-up of 1,122,765 person-years at risk among 73,133 cohort members disclosed 313 incident cases of gastric adenocarcinomas occurring at least 3 years after inclusion into the cohort. There were no statistically significant associations between different levels of salt intake and risk of gastric adenocarcinoma. High consumers of dietary salt were not at increased risk of developing gastric adenocarcinoma compared with low consumers (hazard ratio, 1.0; 95% confidence interval, 0.7-1.4), and no dose-response effect was observed (P(trend) = 0.55). Conclusion: High intake of dietary salt does not appear to increase the risk of gastric adenocarcinoma in this low-incidence western population.