The Process of the Digestive System | Dr. Ali GhaharyWhen we eat food, it digests. This is part of the process of the body’s digestive system, which is made up of the gastrointestinal tract, liver, pancreas and gallbladder. The gastrointestinal tract is made up of a series of hollow, long, twisting, tube-like organs, consisting of the mouth, esophagus, stomach, small and large intestines, and anus. The small intestine is separated into three parts: The duodenum (the beginning), the jejunum (the middle), and the ileum (the end); while the large intestine consists of four parts: The appendix (a finger-shaped pouch), the cecum (the first part of the large intestine), the colon, and the rectum (the end of the large intestine.)

When we consume food, bacteria in our gastrointestinal tract known as flora (also sometimes referred to as microbiome) aide in digestion, as do our nervous system and circulatory system. It is the nerves, hormones, bacteria, blood and organs that all work together to digest the things you eat and drink every day. It is important for the body to digest these foods so that we can get the nutrients from them, such as proteins, vitamins, minerals, fats, carbohydrates, and even water. The body breaks down these nutrients into amino acids, fatty acids, glycerol and simple sugars, and absorbs them for use for cell repair, growth, and energy.

Each part of the digestive system plays its own role. We use our mouth for chewing, which helps break down the food into smaller bits so that it can move through our GI tract more easily. As soon as you swallow the food you eat, your brain automatically signals the muscles of your esophagus which then begins something known as peristalsis – in which food and liquids are moved through the gastrointestinal tract and mixes within each organ. Once food reaches the end of your esophagus, the lower esophageal sphincter comes into play by relaxing and passing food into your stomach. Once in the stomach, food and liquids become mixed with digestive juices and the stomach contents are then emptied into your small intestine. Once in the small intestine, the foods and digestive juices travel through the pancreas and liver, and the nutrients that you are digesting get absorbed into the bloodstream. Foods that don’t digest move into the large intestine, which absorbs that waste and turns it into stool, which is what then results in a bowel movement.

As mentioned, things like the nerves and hormones work together to control the digestive process and send signals back and forth from your gastrointestinal tract to the brain. Hormones are what tell your body to create digestive juices as well as send signals to the brain to let it know if you are hungry or full. Similarly, when you see or smell food, the nerves that connect the brain and spinal cord essentially gives you that feeling of hunger and prepares you to eat. We also have something known as ENS (Enteric Nervous System) which are located within the walls of the GI tract. The ENS either speeds up or delays the movement of food, and controls your gut muscles to either contract or relax.

There are many digestive disorders that someone can be diagnosed with, including but not limited to gastroesophageal reflux disease – also known as GERD or acid reflux, which is one of the most common digestive disorders. This is a condition that causes a burning sensation in the middle of the chest (heartburn) after consuming good. While some people say it happens after eating any type of food, it is commonly triggered by spicy foods such as tomato, peppers, pasta sauce, etc. Other digestive disorders include gallstones, Celiac disease, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, diverticulitis, and even hemorrhoids.