 Specific proteins expressed in the stomach and duodenum involved in defence include mucin proteins, such as mucin 6 and intelectin-1.The time taken for food or other ingested objects to transit through the gastrointestinal tract varies over different studies and is dependent on multiple factors including age, ethnicity, gender, et cetera.Several techniques have been used to measure transit time, including Radiography following a Barium 'labelled' meal', breath Hydrogen Analysis, and Scintigraphic Analysis following Radionuclide 'labelled' meal.