In the last few years, the existence of a clinical profile similar to celiac disease has become important; this disease does not adapt to the traditional diagnosis canons. It is related to a number of patients who are diagnosed as having the celiac disease but present normal serology and small bowel's biopsy. Since the 80's, medical literature reports the existence of a syndrome that connects gluten diet with a toxic effect that produces gastrointestinal symptoms even though the mucosa remains normal. This disease is called the Cooper-Cook syndrome. Over the last few years, there have been lots of publications about this disease under the name "gluten sensitivity". In the following article, three clinical cases that refer to this condition are presented.