Green tea and stomach cancer--a short review of prospective studies

In Japan, green tea has been drunk for a long time. Because it can be drunk casually, many people love drinking it. If such green tea has an effect to prevent stomach cancer, it will be a very convenient way to prevent the disease.

To examine the association between green tea consumption and the risk of stomach cancer, past epidemiologic studies including JACC Study were reviewed.

Among eight case-control studies, five showed risk reduction with a statistically significant difference, and two studies showed risk reduction without a statistically significant difference. The remaining study showed the opposite result. Among six prospective studies regarding stomach cancer, no study showed risk reduction with a statistically significant difference. Four of the six studies showed no relation. In terms of study design, prospective studies, which are considered to be more reliable than case-controlled studies, tend to show no risk reduction. The results of case-control studies and prospective studies present considerably different impressions.

Prospective studies showed no inverse association between the consumption of green tea and the risk of stomach cancer.