| [ Summary ] |
There are geographic and ethnic differences in gastric cancer incidence around the world, as well as trends in each population over time. Incidence patterns observed in immigrant groups changed in relation to the countries they lived in. All of these factors serve to indicate the close association of gastric cancer with modifiable factors such as diet. Infection with Helicobacter pylori is a strong and established risk factor for gastric cancer, but is not a sufficient cause for its development. Substantial evidence from ecological, case-control, and cohort studies strongly suggests that the risk may increase with a high intake of various traditional salt-preserved foods and salt in general, and decrease with a higher intake of fruits and vegetables. However, it remains unclear which constituents in fruits and vegetables play significant roles in gastric cancer prevention. Consumption of green tea is possibly associated with a decreased risk of gastric cancer, although the protective effects have been for the most part identified only among Japanese women, the majority of whom are non-smokers.
Dietary modification by reducing salt and salted food intake, as well as increasing intake of fruits and vegetables, represents a practical strategy to prevent gastric cancer among middle aged-to-elderly Japanese, most of whom are infected with Helicobacter pylori. |