Digestion Basics
You can see that the GI tract is the cornerstone of good physical and mental health. There are many moving parts and it’s impossible to give a one-size-fits-all approach to remedy all of the potential things that can go wrong. However, there are things you can focus on to help optimize your gut function.
In order to fix your gut you must fix your digestion. The health of your gut is dependent on your body’s ability to properly digest the food and nutrients you ingest every day.
Have you ever wondered why when you eat a sandwich you don’t poop a sandwich? It’s because there is a lot that goes into the process of digestion. This is why so much disease happens between your mouth and your anus. If even just one part of the process breaks down, then it will have a cascading effect not just in your gut but also in other parts of your body. If food isn’t properly broken down in your stomach, then by the time it gets to your large intestine it may leak out of your GI tract and into your blood, causing inflammation, autoimmune disorders, disease, and mental health issues.
This is a process that will absolutely require patience. Your gut problems didn’t start in a day and cannot be fixed in a day. But there are simple things you can do every day that will add up over time to help improve your situation. Remember: proper digestion is essential for good health.
Digestion Is a North-to-South Process
Food goes in your mouth and exits through the anus. Between those two points is where all of your gut problems happen.
It Starts in the Brain
Digestion starts even further north than the mouth — it actually starts in the brain. Digestion is an orchestrated process that requires harmony across the autonomic nervous system (ANS). The ANS works in two divisions: sympathetic and parasympathetic.
The Sympathetic Nervous System is your body’s built-in emergency response system, commonly known as fight or flight. This comes from stress. In sympathetic mode, the body is ready for action: heart rate increases, blood flow increases to the muscles, metabolism increases, breathing becomes shallow and more frequent, blood glucose rises, the immune system is suppressed, and your eyes allow more light so vision increases.
In the stomach and intestines, overall digestion and GI motility slows down to divert energy to other parts of the body. In other words, your body can’t break down food and move it through you. If food can’t be properly digested and moved out of you, then you start to experience problems like disease, inflammation, and of course mental problems.
The Parasympathetic Nervous System is otherwise known as “rest and digest.” This is where the organs of your autonomic nervous system can operate to maintain homeostasis within your body. Parasympathetic is a calming place — relaxation, peacefulness. It brings a decrease in heart rate, increased gut motility, slower and deeper breathing, proper blood glucose metabolism, better function of the sex organs, and proper activation of the immune system.
Being in the parasympathetic nervous system is essential for proper digestion, lowering stress, and controlling your hormones. Living in parasympathetic and avoiding sympathetic nervous system as much as possible is essential for good health and longevity.
This all comes down to mentally and emotionally staying in a calm, relaxed state while eating.
The Mouth
Further down from the brain is the mouth. Thoroughly chewing food is one of the most effective, affordable ways to improve digestion. Many gut problems come from poor digestion stemming from food not being properly broken down before it even gets to your stomach.
In today’s modern world many people eat fast. We eat on the go, eat in the car, eat while arguing on social media, eat while watching TV — and the whole time chewing is not fully happening. If food gets into your esophagus without being thoroughly broken down, you begin to experience problems in the stomach.
The other big reason for needing to thoroughly chew is for your mouth to release salivary amylase. This enzyme lives in your saliva and breaks down carbohydrates to be more digestible in the stomach. You want to simplify the job of the stomach as much as possible. The more digested food is before it gets to your stomach, then the easier it is for your stomach to completely break down food.
The Stomach
Once food is in your stomach, it’s broken down by stomach acid. It cannot be overstated how important stomach acid is to your health. Most people don’t think about stomach acid until they are dealing with issues like acid reflux and GERD, and then they turn to pharmaceuticals like antacids, PPIs, and histamine blockers.
In fact, much GERD and heartburn can be attributed to a lack of stomach acid. Low stomach acid leads to a breakdown of the door that stands between your esophagus and stomach, called the esophageal sphincter. This sphincter is supposed to stay closed to keep stomach acid in your stomach. Over time its function can break down because of things like overeating, eating highly processed foods, stress, drugs, caffeine, and low stomach acid. If the sphincter stays open, stomach acid leaks out and creates the feeling of heartburn.
In western medicine, doctors are taught to remedy this with acid-lowering drugs like proton pump inhibitors, but in reality this only makes the problems worse. Food needs to be properly broken down by stomach acid, and if there’s not enough stomach acid then the undigested food causes problems.
Remember what stomach acid is — this is hydrochloric acid, one of the most acidic substances on the planet. If you had a glass of hydrochloric acid and dumped it onto the floor, it would burn a hole through the floor. For many people, this is the sensation you feel in your esophagus and why you turn to medications.
Chyme and the Duodenum
At this point, food has been eaten, chewed, and if you ate in a calm parasympathetic state, your stomach had enough stomach acid to properly break down the food and turn it into chyme. Chyme is the scientific name for this substance that is no longer food but more a product of the stomach’s digestive process.
The chyme is now drenched in stomach acid and is very acidic. You need the chyme to be at a very specific pH level that is acidic enough for its release through the pyloric sphincter into the top part of the small intestine called the duodenum.
In the duodenum, a lot of important things begin to happen. Your duodenum senses the acidity of the chyme and then releases enzymes that not only help further break down the chyme, but also alkalize it and prepare it to be sent down the rest of your GI tract. These enzymes include a host of pancreatic enzymes, bicarbonate, and our friend CCK.
If this process doesn’t happen, you get highly acidic chyme moving through your GI tract, which you will feel as a burning. Many people know this as an ulcer — and again it happens because something broke down up top that didn’t allow the full process to occur that would cool down that digested chyme and make it ready for the rest of your gut.
The Gallbladder and Bile
CCK is especially important because it will trigger the gallbladder to release bile. The bile helps break down fat in the chyme. If you’ve ever noticed your stool floating, or had issues with foul-smelling stools, excessive gas, or cramping, then you may not be fully breaking down fat in your stool, which could mean your gallbladder isn’t emptying.
Not emptying the gallbladder could lead to complications like gallstones and general gallbladder discomfort. For some people, this can be so severe that they get their gallbladder removed. Gallbladder removal surgery is one of the most common outpatient surgeries in America.
As mentioned earlier, the production of CCK is triggered by fat in the diet. This is one of the major reasons that fat is not as bad as it has been marketed. You need it for a major part of your digestive process. Is it any surprise that so many people avoid fat in their diet and gallbladder surgery is such a popular surgery?
Bile is also where all of the toxins go that are filtered from your liver. They go from the liver to the gallbladder to the stool. If you don’t release bile, then you are not getting toxic substances that were cleaned by your liver out of you.
The main thing to understand is the importance of getting it right up top so that things can go right down below. As things go right down below, proper nutrient absorption happens and your body becomes properly primed for nootropic and supplement absorption.