Mediterranean Diet Lowers Gastric Cancer Risk
Design
Dietary and lifestyle information were collected at recruitment. A scoring system was used to estimate degree of adherence to a Mediterranean style diet. The association between diet adherence and gastric cancer risk by location and type was calculated.
Participants
The study included 485,044 subjects (144,577 men) aged 35-70 years old from 10 European countries who were part of the European Prospective Investigation into Cancer and Nutrition (EPIC) Cohort. Mean follow-up was 8.9 years.
Scoring
An 18-unit relative Mediterranean diet score was utilized that rated 9 key components of the Mediterranean diet and allowed estimation of a score for relative Mediterranean diet adherence.
Primary Outcome Measures
Cases of primary gastric adenocarcinoma, their location, and histologic types were recorded.
Key Findings
Participants whose diets scored higher, and therefore most closely matched the Mediterranean Diet, had decreased risk of gastric adenocarcinoma compared to those with low adherence scores. The hazard ratio for those with high adherence compared to low adherence was 0.67; thus their risk for developing cancer was about a third lower. Scores did not affect anatomic location or histologic types. For every 1-unit diet score increase, as calculated by the researchers, the risk for gastric adenocarcinoma decreased by approximately 6%.
Practice Implications
It is time for us to actively encourage patients to adhere as closely as possible to a Mediterranean style diet. This study is just one of a series of recent papers that have looked at the correlation between specific diseases and adherence to a Mediterranean style diet, studies that consistently find benefit.
Components of the Mediterranean diet have already been individually shown to affect gastric cancer risk. González et al reported in 2006 that meat consumption affected gastric cancer risk and found that total red and processed meat intakes were associated with an increased risk of gastric non-cardia cancer, especially in H. pylori antibody-positive subjects.
González, in another 2006 paper, reported on fruit and vegetable consumption and risk of gastric cancers. A possible negative relationship was seen between total vegetable intake (HR 0.66; 95% CI 0.35–1.22 per 100 g increase) and onion and garlic intake (HR 0.70; 95% CI 0.38–1.29 per 10 g increase) with risk of intestinal cancer. Nonsignificant negative associations were seen between citrus fruit intake and the cardia site (HR 0.77; 95% CI 0.47–1.22 per 100 g increase) and a nonsignificant negative association for vegetable intake and for citrus intake (calibrated HRs 0.72; 95% CI 0.32–1.64 and 0.77; 95% CI 0.46–1.28 per 100 and 50 g increase, respectively) and esophageal adenocarcinoma. Citrus fruit consumption may have a role in the protection against cardia gastric carcinoma and esophageal adenocarcinoma.
A 2007 paper found that cereal consumption had a much stronger effect against gastric cancer than fruit or vegetables. High intakes of cereal fiber reduced gastric cancer risk by about 31% [adjusted HR for the highest versus lowest quartile of cereal fiber 0.69, 0.48–0.99].