The human digestive system is the means by which tissues and organs receive nutrients to function. The system breaks down food, extracts nutrients from it, and converts them into energy.
The digestive tract begins this involuntary process once food is consumed. Saliva begins the breakdown of food, and other enzymes in the digestive tract extend this process. As digestion continues, the food is propelled from organ to organ through muscular contractions called peristalsis.
The largest parts of the digestive system include:
- Esophagus: A hollow tubular organ in the neck and chest area that connects the mouth to the stomach. Muscles here propel food to the stomach.
- Stomach: A large organ that holds and digests food through a cocktail of enzymes and acids. Food remains here for two to eight hours.
- Liver: This organ helps filter toxins from the blood and produces bile, which helps break down proteins, carbohydrates, and fats.
- Gallbladder: This sac-like organ stores bile produced by the liver and then releases it as necessary.
- Pancreas: This organ produces insulin, which aids in the metabolism of sugars.
- Small intestine: The small intestine receives food from the stomach and begins to break down the food while absorbing the majority of its nutrients.
- Large intestine: This organ is filled with billions of harmless bacteria that turn food into feces while removing water and electrolytes for the body’s use.
- Rectum: At the end of the large intestine, this small space is a temporary storage area for feces.
- Anus: This is the external opening of the rectum, through which feces are expelled.
The connection between all of these organs and their fluids requires a delicate balance that can easily be disrupted by numerous factors, including diet, stress, disease, and more.
Common digestive problems include:
- Acid reflux
- Food poisoning
- Irritable bowel syndrome (IBS)
Other problems are connected to serious conditions that affect portions of the digestive system, including:
- Celiac disease
- Crohn’s disease
- Gastroesophageal reflux disease (GERD)
- Cirrhosis of the liver
- Cancers: colorectal, stomach, pancreatic, intestinal, and liver