Although GIT sounds like a British slang term, it’s actually something much more important. To kick off our series on Internal Organs, we’ll start with a discussion around the golden line that runs through each of us: The Gastro-Intestinal Tract – also known as our GI-Tract.
The simple version is that food goes in one end and something rather nasty comes out the other
– but there is actually much more to it than just that. Our GI-Tract acts both as a furnace that burns fuel to keep our bodies going as well as being a great component of our overall health. Issues such as heartburn and indigestion, as well as leaky-gut syndrome and constipation, all relate to this very important GI-Tract. Firstly, let’s get to know this “golden line”: the GI-Tract is made up of a series of hollow organs, all connected by a long, convoluted tube, right from the mouth to the anus. These organs include:
- Small intestine
- Large intestine
A great way to understand the GI-Tract and what happens to food that moves through it, is by thinking of a really bad teeny-bop movie: the beginning looks fairly promising, the middle is just confusing and filled with events that are supposed to bring about change in the lead character… but after all that change happens, it still has a really crappy ending. As a bonus, you usually feel relieved once it’s all done and dusted, and you can finally get on with your life again. But putting my puns and opinion on teenage movies aside,
the digestion and health of your GI-Tract is actually vitally important.
It is what enables your body to get, take in and use the nutrients it needs to keep you going (which includes proteins, fats, carbohydrates, vitamins and minerals) through a process of energy generation, growth and repair of your body. Each part of the GI-Tract has an important role to play in this process:
- Mouth: The mouth serves as the place where usable food is crushed into smaller pieces for swallowing. The food is then pushed to the back of the throat and into the oesophagus by
- Oesophagus: Peristaltic movements (which are wave-like contractions of your digestive muscles) move the swallowed food down towards the lower oesophageal sphincter. Peristalsis works by contracting the muscle behind the mass of food, and relaxing the muscles in front of it, ultimately pushing it through the digestive tract. Once the food has reached the lower oesophageal sphincter (which is a ring-like muscle that functions as a tightly sealed doorway), it opens to allow the food to pass into the stomach. It also closes again immediately to prevent the stomach contents from rising back up into the oesophagus.
- Stomach: Your stomach muscles (which are not your abs, by the way, but your actual stomach organ), mixes the food together with digestive juices. It is pretty much the ultimate food processer, that blends everything together and slowly empties the contents out into the small intestine.
- Small Intestine: Here, the food that has been mushed in the stomach gets mixed with special juices from the pancreas, liver and intestine and then gets pushed forward into the large
intestine, where it is further digested. The small intestine is the first “stop” on the food’s journey where water and nutrients can be absorbed, due to it being partially broken down (or digested).
- Large Intestine: In the large intestine, more water and nutrients are absorbed, and as a result, the liquid starts to change to stool, or faecal matter (which is a fancy word for poop), which is then pushed further along to the rectum, through peristaltic movements.
- Rectum: This is the tail-end of your large intestine, and it is the final stop for the digested food. Now that all the useful matter has been taken up from the food you have eaten, the leftover waste, in the form of faecal matter or stool, is pushed out through the anus during bowel movements.
In a nutshell, this is the summarised version of the magical journey from cupcake to crapcake, and all the (important) scenic pitstops your food must make in between. Now that you know how the process works, stay tuned for our next discussion on how the GI-Tract can affect your overall health if not functioning correctly, and how this impacts you on your fitness journey.