BACKGROUND: Positive patch tests to balsam of Peru (BOP) or fragrance mix (FM) suggest the possibility of systemic contact dermatitis from balsam-related foods and spices. OBJECTIVE: This was a retrospective study to determine whether avoidance of balsam-related foods results in an improvement of dermatitis in these patients. METHODS: A review of the records of all patients seen from July 1 to Dec 31, 1998 with positive patch tests to BOP, FM, cinnamic aldehyde, and balsam of tolu was performed 9 to 14 months after their evaluation in a tertiary dermatology center. All patients were contacted via telephone to assess the status of their dermatitis and whether they were able to note any specific balsam-related food allergies. RESULTS: A total of 75 patients were identified, and 71 could be contacted. Fourteen were only allergic to BOP or FM on testing; 31 were positive to BOP/FM and other allergens with presumed relevance to BOP/FM; 26 were positive to BOP/FM and others with other allergens felt to be responsible for the dermatitis and were not placed on a BOP diet. Excluding this last group, 21 of 45 (47%) had complete or significant improvement that they related to dietary modification. Ten did not modify their diet, with 8 reporting no improvement. Eight improved with fragrance or other allergen avoidance only, and 6 modified their diet unsuccessfully. Most commonly implicated foods included tomatoes, citrus, and spices. CONCLUSION: Almost half of the subjects with positive patch tests to BOP or FM who followed a BOP reduction diet reported significant to complete improvement of their dermatitis.