Digestive Health A Look Inside Your Digestive System By Charles Daniel Charles Daniel Charles Daniel, MPH, CHES is an infectious disease epidemiologist, specializing in hepatitis. Learn about our editorial process Updated on April 10, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Robert Burakoff, MD, MPH Medically reviewed by Robert Burakoff, MD, MPH LinkedIn Robert Burakoff, MD, MPH, is board-certified in gastroentrology. He is the vice chair for ambulatory services for the department of medicine at Weill Cornell Medical College in New York, where he is also a professor. He was the founding editor and co-editor in chief of Inflammatory Bowel Diseases. Learn about our Medical Expert Board Print The digestive system consists of several organs that function together to break down the foods you eat into molecules your body can use for energy and nutrients. The digestive tract includes the mouth, esophagus, stomach, intestines, and anus. So-called "accessory" organs include the liver, pancreas, and gallbladder; food doesn't move through these organs, but they secrete hormones and chemicals that are essential to digestion. Here's what to know about your digestive system organs and functions. The Mouth WIN-Initiative / Getty Images Digestion begins in your mouth. Your teeth grind the food you eat and mix it with saliva to form a kind of ball, known as a bolus. During the mixing, an enzyme called salivary amylase starts breaking down carbohydrates. Once the food is soft and relatively flexible, the tongue pushes it to the back of your mouth and into the esophagus. The Esophagus SEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY / Getty Images Your esophagus is a flattened muscular tube that connects your mouth to your stomach. As food is swallowed, your esophagus expands. It takes food about three seconds to pass through your esophagus, depending on the texture and consistency. Common problems of the esophagus include heartburn, acid reflux, and gastroesophageal reflux disease (GERD), which are caused by acid flowing up from the stomach and irritating the lower part of the esophagus. Anatomy, Structure, and Function of the Esophagus The Stomach Toshiro Shimada / Getty Images Your stomach is a J-shaped muscular pouch, which receives food from your esophagus and sends it to your small intestine. Inside your stomach, food is mixed with enzymes and acid until it becomes a liquid, called chyme. The stomach is the main site for protein digestion and uses powerful enzymes, known as pepsins, as well as hydrochloric acid, to digest foods like meats, milk, and cheese. The Small Intestine OpenStax College / Wikimedia Commons / CC-BY-3.0 The small intestine is an approximately 20-foot-long muscular tube, which is divided into three distinct parts: the duodenum, the jejunum, and the ileum. Each of the three parts plays a major role in digestion and absorption. Absorption is a crucial part of the digestive process that brings the molecules from the digested food into the blood and, ultimately, the cells. Problems with your small or large intestine can affect the way your body absorbs and digests food, leading to malnutrition. People who are missing parts of their intestines or have limited intestinal mobility may require total parenteral nutrition (TPN), a type of nutrition that bypasses the digestive system. What Does the Small Intestine Do? The Large Intestine PIXOLOGICSTUDIO/SCIENCE PHOTO LIBRARY / Getty Images The last part of the digestive tract, the large intestine, is a muscular tube that is about 6 feet long. It's divided into the cecum, the colon, and the rectum. Together, these segments complete any nutrient absorption and process the waste into feces. Problems with your large intestine can be caused by diseases such as inflammatory bowel diseases (IBD) like Crohn's disease and ulcerative colitis as well as celiac disease. If parts of these organs become seriously diseased, they may require surgical removal. When this happens, an ostomy may be necessary to aid digestion and elimination. The Function of the Large Intestine The Anus The anus is the last organ of the digestive system. It is a 2-inch long canal consisting of pelvic floor muscles and two anal sphincters (internal and external) which allow you to hold in feces until you are able to get to a bathroom to release the contents into the toilet. The Pancreas PIXOLOGICSTUDIO / Getty Images The pancreas is one of the three "accessory" digestion-related organs. Your pancreas assists your small intestine by secreting pancreatic juice, a liquid filled with enzymes and sodium bicarbonate that is able to stop the digestion process of pepsin. It also secretes insulin, which helps your body regulate your blood sugar. The Function of the Pancreas The Liver PIXOLOGICSTUDIO/SCIENCE PHOTO LIBRARY / Getty Images Your liver has many functions. First, it produces bile, which the small intestine uses to help digest the fats in food. It also metabolizes proteins, carbohydrates, and fats; helps regulate blood sugar levels; stores glycogen for quick energy; makes fibrinogen, which clots blood; makes vitamin A; and recycles worn-out red blood cells. Diseases of the liver, such as hepatitis, can have major complications that affect other parts of the body as the liver is involved in so many essential functions, like digestion. The Functions of the Liver The Gallbladder MedicalRF.com / Getty Images Tucked under the liver, your gallbladder is a storage container for bile, a yellow-green fluid made up of salts, cholesterol, and lecithin. Your small intestine uses bile to digest fats. Most people never think about their gallbladder until a problem with gallstones or gallbladder disease, such as cholecystitis, develops. If you have a gallbladder-related disease, you may experience jaundice. This happens when the bile cannot leave the gallbladder. Instead, the bile enters the bloodstream, which can cause your skin, eyes, and nails to appear yellow. The Anatomy of the Gallbladder Frequently Asked Questions What is the most common disorder of the digestive system? Irritable bowel syndrome (IBS) is the most common disease diagnosed by gastroenterologists (doctors who specialize in the digestive system). It’s estimated that between 10% and 15% of adults suffer from (IBS). Learn More: Overview of Irritable Bowel Syndrome What are accessory organs in the digestive system? The pancreas, liver, and gallbladder are considered accessory organs. Food does not move through them, as it does in the gastrointestinal tract, but these organs release hormones and chemicals that are essential to digestion. Learn More: The Role of Enzymes in Digestion How are digestive system organs affected by type 1 diabetes? In type 1 diabetes, your pancreas does not produce insulin, causing your blood sugar to rise. Another digestive complication of type 1 diabetes is gastroparesis, in which it takes longer than usual for the stomach to empty its contents into the small intestine. Learn More: What Is Gastroparesis? Was this page helpful? Thanks for your feedback! Gas pain? Stool issues? Sign up for the best tips to take care of your stomach. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 13 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. National Cancer Institute. SEER Training Module. Accessory organs. Bornhorst GM, Singh RP. Bolus formation and disintegration during digestion of food carbohydrates. Compr Rev Food Sci Food Saf. 2012;14(4):431–445. doi:10.1111/j.1541-4337.2011.00172.x National Institutes of Health, National Institute on Deafness and Other Communication Disorders. Dysphagia. National Institute of Diabetes and Digestive and Kidney Diseases. Acid reflux (GER & GERD) in adults. American Society of Gastrointestinal Endoscopy. Quick anatomy lesson: Human digestive system. National Institute of Diabetes and Digestive and Kidney Diseases. Your digestive system & how it works. Aggarwal L, Sattavan S, Lal R, et al. 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