Adherence to Mediterranean Diet and risk of esophageal, stomach and pancreatic cancer: a case-control study in Spain
METHODS: A total of 223, 390 and 165 incident cases of esophagus, stomach and pancreas cancer histologically confirmed, and 455 controls frequency matched by sex, age and province of residence were included in this hospital-based case-control study in Valencia, Spain. Personal interviews were carried out to assess lifestyles and usual diet five years prior to the diagnosis by a validated food frequency questionnaire. To assess adherence to Mediterranean diet we estimated the rMED (range 0-18) based on reported consumption for nine components (fruit, vegetables, legumes, cereals, fish, olive oil, dairy products, total meat and alcohol consumption). rMED was grouped in three categories according to previous studies (low 0-6; medium 7-10; high 11-18). Multinomial logistic regression was used to estimate adjusted odds ratios (OR).
RESULTS: A higher adherence to rMED (11-16) was associated with a statistically significant lower risk of esophageal cancer, OR=0.43 (95%CI: 0.25-0.54) and pancreatic cancer, OR=0.69 (0.54-0.87) while no significant association was found for stomach cancer, OR=0.89 (0.70-1.12). When histological type was considered, the protective effect observed for esophageal cancer was mainly observed for the squamous cell carcinoma. When individual components of the rMED were analyzed, fruit and vegetables were the only components showing significant protective effect for the three cancers.
CONCLUSIONS: Our study provides evidence that a higher adherence to Mediterranean Diet is associated with a significant reduction in the risk of esophagus and pancreas cancer in an adult Mediterranean population. Fruits and vegetables were the main components responsible for this protective effect.