A diet rich in fruits and vegetables is associated with a reduced risk of head and neck cancer. This study was designed to assess the efficacy of an intervention to increase fruit and vegetable consumption and improve overall diet quality in patients with early stage head and neck cancer at risk for second primary cancer. The study was a crossover-controlled design with each patient being his or her own control. Patients received usual care during the control period followed by a clinical-based intervention grounded in the Social Learning Theory for 3 months. Measurements were taken at baseline, 6 months, and 12 months. The intervention consisted of a face-to-face counseling session, a phone call, and three mailings. Findings from this study indicate that these patients increased their intake of fruits (number of servings and variety), vegetables (number of servings), and improved overall diet quality while exposed to the intervention as compared with usual care.