What is the Digestive System? | Digestion 101 | Digestive Disorders | Taking Care
Overview
Eating and drinking are some of life’s greatest pleasures. You can be forgiven for not thinking of these actions in terms of their biological function.
Besides breathing, taking in and excreting food and liquids keep us alive and functioning.
The digestive system is a vast, highly complex set of organs taking up a lot of real estate in our bodies for a good reason – the raw material (food, liquids) that enters our system via our mouths gets broken down into much smaller parts and then gets directed all around our bodies to where these extracted nutrients are needed.
Everyone has experienced digestive symptoms such as upset stomach, heartburn, nausea, constipation, or diarrhea. There are a lot of organs in this complex framework, and there is undoubtedly potential for occasional problems.
Let’s look at how this incredible, vital system works and what we can do to keep it healthy.
What is the Digestive System?
The primary purpose of the human digestive system, namely the gastrointestinal (GI) tract and its organs, is to break down food into smaller components until the extracted nutrients can be absorbed and assimilated into the body.[1]
The gastrointestinal tract comprises the oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine. The organs of this system are known as accessory organs: the teeth, tongue, salivary glands, liver, gallbladder, and pancreas.[1]
Digestion 101
The digestion process starts in the mouth with saliva and digestive enzymes secreted as we chew food. This action begins to break down starches, converting them into a soft ball that travels through the esophagus to the stomach, where food mixes with acid and enzymes for further breakdown.[2]
From there, the processed food gets moved into the small intestine. Bile from the liver breaks down fats. Enzymes from the pancreas and glands in the intestines convert carbohydrates, proteins, and fats into their molecular components, which then get absorbed into the bloodstream and directed to where they are needed.[2]
Certain foods, such as fiber, cannot be digested in this manner. These pass into the large intestine, which forms feces for excretion.[2]
Digestive Disorders
With such a vast and complex system of organs, enzymes, and functions, along with the overall quality of the foods we ingest getting lower over time, digestive disorders rank among the top health issues people experience.
Some common digestive issues include:[3]
Heartburn: Usually caused by stomach contents backing up into the esophagus
Colitis: Inflammation of the bowel
Ulcers: Tears in the mucus membrane of either the stomach or duodenum (part of the small intestine)
Irritable bowel syndrome (IBS): A disorder thought to be caused by a sensitive colon or immune system.
Inflammatory bowel disease (IBD): A group of disorders that cause chronic inflammation in the intestines
Gastroenteritis: Also known by its colloquial name “stomach flu,” it is the inflammation of the stomach and intestinal lining
Symptoms of digestive issues can include constipation, diarrhea, nausea, vomiting, persistent heartburn, bloating, and abdominal pain. Please see your doctor if you experience any of these if they are ongoing.
Taking Care
There are some lifestyle-centered methods to ensure that your digestive system (as well as your whole body) functions well for a lifetime.
- Eat a healthy, balanced diet that includes lots of fiber
- Drink lots of water (get 8-10 glasses of water per day)
- Don’t smoke
- Reduce stress – the digestive system is especially prone, so try to learn ways to relax and unwind from life’s challenges
- Exercise – nothing keeps things moving well in the body than getting physical activity – aim for 30 minutes per day
If you try to manage your digestive issues through lifestyle measures and are unsuccessful, talk to your doctor. You may have an undiagnosed condition that requires medical attention.
References:
- Ogobuiro, I., Gonzales, J., & Tuma, F. (2022). Physiology, Gastrointestinal. In StatPearls. StatPearls Publishing.
- Patricia, J. J., & Dhamoon, A. S. (2022). Physiology, Digestion. In StatPearls. StatPearls Publishing.
- Greenwood-Van Meerveld, B., Johnson, A. C., & Grundy, D. (2017). Gastrointestinal Physiology and Function. Handbook of experimental pharmacology, 239, 1–16. https://doi.org/10.1007/164_2016_118
