Study population: 20 healthy individuals, strictly asymptomatic, of both sexes, in different age groups will be included.  Inclusion Criteria:  Adult individuals without any comorbidity, strictly asymptomatic. Age> 18 years. Informed consent signature. Carrying out a varied, non-restrictive diet. Negative blood tests including celiac serology, H. pylori serology and celiac disease genetic study (will only be accepted if they have positive DQ2.2 allele). Normal esophagogastroduodenoscopy. Grossly and microscopic normal duodenal mucosa.  Exclusion Criteria:  Refusal of the individual to participate. Severe disease (heart disease, lung disease, liver disease, bleeding disorders, neoplasms, etc.). Personal history of celiac disease and / or inflammatory bowel disease. Pregnancy and/or lactation. Age> 45 years. BMI> 28. Presence of any current digestive symptoms (negative responses must be met in all items of the dyspepsia test). Family history of 1st or 2nd degree of celiac disease or inflammatory bowel disease. Potentially contagious diseases (HIV, HCV, HBV, tuberculosis, Covid19, ...). Trips to tropical countries in the last 6 months. Presence of coagulopathy or use of anticoagulant treatments. Consumption of any drug (including NSAIDs) in the last 4 weeks. Strict vegetarian, vegan or gluten-free diet. H. pylori positive. DQ2.5 positive and /or DQ8 positive Positive celiac serology (anti-transglutaminase> 2 U / mL). Active smoking. Habitual alcohol intake >40 g in men and 20 g in women. Alcohol intake in the previous 3 days. Esophagus-gastro-duodenoscopy with macroscopically abnormal mucosa.