A varied diet may have a favorable role against digestive tract cancers. We analyzed the relationship between diet diversity (i.e. measured by the number of different foods consumed at least once per week) and the risk of esophageal cancer. We considered data from a case-control study conducted between 1992 and 1997 in northern Italy on 304 squamous cell esophageal cancer cases below age 78 years and 743 controls admitted to hospital for acute, nonneoplastic conditions, unrelated to tobacco or alcohol consumption. There was a significant inverse association for total diet diversity: the multivariate odds ratio (OR), adjusted for age, sex, area of residence, education, tobacco smoking, alcohol drinking and non-alcohol energy intake was 0.42 (95% confidence interval, CI: 0.25-0.71) for subjects in the highest versus those in the lowest quartile of diversity. Inverse relations were also found for diversity within vegetables (OR 5 0.34, 95% CI: 0.21-0.55) and fruits (OR 5 0.51, 95% CI: 0.33-0.80). No significant association was found for meat and cereal diversity. These results add epidemiological support to the dietary guidelines recommending a more varied diet, particularly in fruit and vegetables, for esophageal cancer prevention. ' 2008 Wiley-Liss, Inc.Key words: esophageal cancer; diet; case-control study; Italy; fruit and vegetables In Europe and North America, esophageal squamous cell carcinoma is strongly related to tobacco and alcohol consumption, but various aspects of diet have a role on risk. 1 In particular, a high intake of fruit and vegetables has been linked to a lower risk of esophageal cancer. [1][2][3] Most epidemiological studies, however, have addressed this association by considering individual food items, and limited attention has been paid to the analysis of their joint effect by considering dietary patterns.Food diversity (i.e. the variety of foods consumed) has been recommended to achieve a healthy diet in cancer prevention. 4,5 Diet diversity has been inversely related to all-cause mortality in the First National Health Epidemiologic Follow-up Study. 5 Inverse associations were also found with upper respiratory and digestive tract cancers, including oral and pharyngeal, 6,7 laryngeal cancer, 8 gastric, 9 and colorectal. [10][11][12][13] No study, to our knowledge, has investigated the relation between diet diversity and esophageal cancer risk.To assess the role of total and specific food group diversity on the risk of esophageal cancer, we analyzed data from a case-control study conducted in northern Italy.
Material and methodsA case-control study of cancer of esophagus was conducted between 1992 and 1997 in the provinces of Milan, Pordenone and Padova in northern Italy. 2 Cases were 304 patients (275 men and 29 women; median age: 60 years, range: 39-77 years) admitted to major teaching and general hospitals in the study areas, with incident, histologically confirmed squamous cell cancer of the esophagus, diagnosed no longer than 1 year before the interview.Controls were 743 subjects (593...