87 (1.6% of all patients) predominantly adult patients with IgE-mediated food allergy (FA), were seen at the Allergy Unit of the University Hospital of Zurich during the year 1998. The age of manifestation was between 1 and 60 years, with a mean of 27.7 years. These patients were classified according to the way of sensitization (via gastrointestinal tract or via aerogeneous allergens with crossreactivities with foods) and the age of manifestation into the types A, B, C of food allergies, according to the concept of Pichler [1998]. FA type A is seen in infants and small children, which get sensitized to food proteins via the gastrointestinal tract. FA type B is due to crossreactivities of IgE, which are originally directed to aerogeneous allergens in pollen, latex, dust mites, etc. FA type C does not appear predominantly in atopic persons. The affected persons get sensitized via gastrointestinal tract to selected, stable food proteins. In the present series, only 7 children (8%), 1 - 4 years old, belonged to type A and the FA was higly associated with a familial, or personal atopy. The main food, eliciting symptoms of the skin and gastrointestinal tract were nuts and eggs. This small group is not representative as such cases are seen by pediatricians. FA type B was diagnosed in 64 patients (73.6%), aged between 6 - 60 years. The peak of age manifestation was between 21 - 30 years. 64.1% were females; 78.1% of the patients had a pollen allergy and, therefore, the main crossreactivities were birch or mugwort pollen associated (80.7%). The latex-fruit was seen in 18.8%, the house dust mite-crustaceans in 12.5%, the grass-cereals and the ragweed-melon in 4.7% each. Only 1 patient (1,6%) presented itself with a pork-cat syndrome. Fruits, vegetables, hazelnut and spices elicited mainly an oral allergy syndrome (OAS) (in 67.2% of the cases), but also symptoms of the skin (urtikaria in 48.8%) and the airways (65.6%, particularly as dyspnea (48.8%)). The main food allergens in this group were apple (40.6%), celery (34.4%) and hazelnut (23.4%). FA type C represents 16 patients (18.4%, age between 12 and 58 years; 62.5% were females. This group is heterogeneous; only 31.3% had a family history and 18.8% had a personal history of atopic diseases, and the symptoms due to FA were predominantly acute or recurrent. Fish and crustaceans, meat and kiwi were predominant as food allergens and often elicited symptomes of the skin and airways. An OAS was rare. In 1 previoulsy nonatopic patient, the way of sensitization was the skin due to occupational contact with fish and crustaceans (contact urticaria syndrome). This may represent a fourth type (D) of FA.