The effect of gastric digestion on food allergy.

PURPOSE OF REVIEW: The role of the stomach as the primary location of protein digestion is very well recognized, leading to classification of proteins as digestion-resistant or digestion-labile. This review analyses the role of gastric digestion in food allergy.

RECENT FINDINGS: Hindrance of gastric digestion by elevation of the gastric pH, the therapeutic goal of anti-ulcer medication, was recently shown to trigger food allergy via oral sensitization in a murine food allergy model. The relevance in humans was assessed in an observational study of 152 gastroenterological patients who were medicated with anti-ulcer drugs due to dyspeptic disorders. Twenty-five percent of all patients developed a boost or de-novo IgE formation towards regular constituents of the daily diet. The clinical relevance of the induced antibodies was confirmed by positive skin and oral-provocation tests. Moreover, the importance of gastric digestion was also proven for food-allergic patients, as the allergenicity of allergens were reduced up to a 10,000-fold by gastric digestion.

SUMMARY: These recent studies indicate for the first time the important gate-keeping function of gastric digestion, both in the sensitization and the effector phases of food allergy.