Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a special form of adult food allergy when allergic symptoms are elicited when triggering factor such as exercise is added after ingestion of wheat. Besides the molecular characteristics of wheat proteins, the gastric function is decisive for the allergenic potential. Alterations in the gastric milieu are frequently experienced during a lifetime either physiologically or as a result of gastrointestinal pathologies. Helicobacter pylori infection can lead to hypoacidity and enhance the sensitization risk for food allergens in adults. Gastric transit of food proteins and alterations in the gastric secretion can be disturbed after bariatric surgery such as the laparoscopic adjustable gastric binding (LAGB) procedure used commonly as therapy for morbid obesity. We report a case of WDEIA in a 42-year-old man with H. pylori positive gastritis, 2 years after bariatric surgery and no history of allergy previously. Our presented case strongly suggests that H. pylori-associated gastritis and gastric anatomy and functional changes after adjustable gastric banding lead to the alterations in gastric milieu and may contribute to a development of food allergy in previously non-sensitized patients.