What Really Goes on During Digestion?
To live a life full of health and vitality, the most crucial human need is nourishment! Without proper digestion, it’d be difficult to receive enough macronutrients to give us the energy we need to survive. Nor would we get adequate nutritional benefits from water, vitamins, minerals, and phytonutrients, that are necessary to keep our body functioning optimally. Which means, increased risk of chronic disease, nutritional deficiencies, and less than optimal health!
As if nourishment wasn’t an important enough human need, we also have our immune system that relies on the health of our digestion. Our immune system is our body’s line of defense that security checks everything that comes in through our gastrointestinal tract. What our body absorbs for nourishment, or gets discarded as waste, gets decided right at the lining between our gut and bloodstream. It is THE contact point between the external world and our body.
Healthy digestion is only possible if our gut lining is functioning optimally. Because if not, a dysfunctional gut lining means our immune system won’t be able to properly defend against pathogens, allergens, harmful bacteria, viruses, or properly break down and absorb essential nutrients.
What immune system defenses are housed in our gastrointestinal lining?
Our gastrointestinal lining houses 3 main levels of defense that make up our immune system – functions as a physical barrier of protection, is the site of innate immune responses, and adaptive immune responses. Our innate immune response is the one we were born with – our body is built to recognize what is innately dangerous to our health and acts to destroy it without having to evaluate what it is first. Our adaptive immune response goes through an evaluation process, learning what is being digested, whether it’s to be recognized as safe, flagged as safe, and let through. Or what is dangerous, then flagged as dangerous for future encounters, then destroyed. All three of those levels work together to keep us healthy and start in our gut!
What digestive components are necessary for optimal immune system function?
The most important functions of our gastrointestinal tract that serve to support our immune system are – our stomach acid & enzymes, our intestinal wall itself, the mucosal layer of our intestinal wall, and our gut microbiome. The first step of digestion begins with chewing and starts the process of breaking down proteins. The next step of digestion is in the stomach with hydrochloric acid (HCL), and an enzyme called pepsin (enzymes function to speed up a chemical process). This strong acid and enzyme work together to break down the proteins you consumed, into smaller polypeptides. HCL and pepsin also fight off pathogens at our stomach lining, while also disarming other pathogens before they reach our small intestine.
You all know how important healthy gut bacteria is, right? If we don’t have enough HCL or pepsin being produced in the stomach (which can be caused by zinc or B-vitamin deficiencies from poor diet, stress, or certain medications), there will be an increase in harmful bacteria entering our gut microbiome. Too many bad bacteria will create imbalance and result in a cascade of inflammatory responses starting in our gut-associated lymphoid tissue (GALT), just outside the lining of our intestinal wall.
That inflammatory response can not only weaken our immune system defenses, but also weaken the tight junctions that keep our intestinal lining strong and secure. This creates a leaky gut! Which in turn, will allow larger pieces of food particles to squeeze through the physical barrier of our intestinal lining, into our bloodstream, causing our adaptive immune system to go haywire, and exacerbating our inflammatory immune response even further.
Lastly, our intestinal lining has a protective mucus to also keep harmful microbes from invading our body. Just like our nasal cavity and mucus membranes, if there isn’t a healthy layer of mucous catching the “bad” stuff, infection can set in, and we get sick! This mucus layer in our gut also serves to create fuel for our epithelial cells which are what make up our very intricate and complicated intestinal wall.
Woo, that’s a lot to “digest” isn’t it? That’s hardly even scratching the surface believe it or not! But not to worry though, although the science of how our digestive system and immune system work is extremely complicated, you at least now have a basic understanding, and I’ll give you some simple steps for how you can help keep these systems running optimally!
3 Best things you can do for your gut health and immune system –
- Probiotics – whether through your diet by eating fermented foods, or a supplement, ensuring you consume probiotics that feed your healthy gut bacteria will help to keep digestion going well, and your immune system balanced.
- Chewing – when we eat too fast, and don’t chew enough, it’s harder for our stomach to break down those bigger fragments of protein. Which means there is a higher chance of larger proteins entering our small intestine and causing inflammation. So, slowing down, and chewing your food not only physically helps your body break up your food, but also releases more enzymes to help the digestive process even further. So, chew, chew, chew!
- Eat the rainbow – eating a diet high in vibrant whole foods will ensure you’re getting a variety of vitamins, minerals, and phytonutrients, while also decreasing your chances of nutrient deficiencies that can lead to low stomach acid production.
At STRONGLIFE Functional Medicine in Lithia, FL, Dr. Justin Scott can help you address any underlying issues, whether you realize they’re there or not, and improve your overall health.
“I hope that you found this as valuable as my patients have over the years. If you’re interested in a patient-centered process that takes into account all aspects that affect your health, then I would encourage to visit our website at www.stronglifefunctionalmedicine.com to see how we help our patients improve their health and to find if you are a good candidate for a Functional Medicine approach.”
