The objective of this study was to examine the associations between dietary patterns and the risk of Barrett's esophagus, a precursor to esophageal adenocarcinoma. The authors conducted a case-control study within the Kaiser Permanente Northern California population between 2002 and 2005. Patients with a new diagnosis of Barrett's esophagus (n = 296 cases) were matched to persons with gastroesophageal reflux disease (n = 308) without Barrett's esophagus and to population controls (n = 309). Dietary information was obtained from a validated, 110-item food frequency questionnaire. A principal component analysis was used to identify major dietary patterns. Two major dietary patterns were "Western" (high in fast food and meat) and "health-conscious" (high in fruits, vegetables, and nonfried fish). When cases and population controls were compared, strong adherence to the health-conscious dietary pattern was inversely associated with Barrett's esophagus (odds ratio = 0.35, 95% confidence interval: 0.20, 0.64; fourth vs. first quartile comparison). In contrast, data suggested an adverse effect of the Western dietary pattern on the risk of Barrett's esophagus, although no dose-effect relation was found. Results suggest strong associations between a diet rich in fruits and vegetables and the risk of Barrett's esophagus.