What you eat is only half the equation, absorbing and delivering nutrients is the other half. In other words, just because you ate something, doesn’t mean that you absorbed and extracted its nutrients and delivered them to specific parts of your body.
Digestion 101
The digestive system is 26ft long, it starts at your mouth and ends in your butt. The GI tract selectively absorbs nutrients while protecting you from toxins and pathogens. In a nutshell, the way it works is by involuntary muscular contractions that breakdown food down into small molecules, which then make their way into cells to be useful, the rest that is not useful or what your body doesn’t want to use is excreted. Amongst the many roles of the GI tract, here are a few of them:
-Process nutrients and minerals
-Acts as a barrier for chemical and physical pathogens
-Excretes waste
-Detoxifies harmful substances
-It contains the enteric nervous system, also known as “the second brain”
-Excretes hormones
-Regulates immune system
-Its involved in social engagement and emotions
Our behavior, diseases and intolerances tend to mess with digestion, which in turn makes the absorption of nutrients and nutrient delivery an uphill battle.
It all starts in our brain. Hunger activates systems in our brain that essentially makes us search for food. When we start smelling or seeing food, or body starts getting ready to start the digestion process. Digestion is controlled by the autonomic nervous system, which is divide in two sides:
-The sympathetic nervous system (SNS) or “fight or flight” mode. SNS activates through intense activity or stress. When SNS is activated, digestion shuts down via norepinephrine.
Norepinephrine actives when the sympathetic response is activated, shuts down digestive process, so more energy goes to your limbs to “ fight for flight”.
-The parasympathetic (PSNS) or “relax and digest” mode. PSNS activates through rest and relaxation, it promotes digestion.
This is the main reason why high-performers or people who are constantly internally or externally stressed have a hard time with any physiological adaptation. They are constantly interrupting the digestion process, which in turn messes with their appetite, hunger and fullness.
Once your brain got you to eat food, chewing it breaks down your food into smaller pieces. Your saliva, moistens these pieces and saturates them with digestive enzymes like lipase and amylase that help break them down once you swallow.
Once you swallow, the esophagus transports the shredded pieces into your stomach.Most carbohydrates are then broken down into glucose and exit the stomach first, most proteins follow carbohydrates and are broken down into amino acids and finally, most fats are broken down into fatty acids and are the last ones to leave the stomach.
This is good to know because someone who might need a quick energy boost without wanting a big meal might only need carbohydrates, versus someone that has a hard time with feeling hungry all the time might need meals that are higher in fat so they feel satisfied for longer.
After spending time in the stomach, a semi-fluid mass containing the partially digested food called chime, is transported into the small intestine where most of the nutrients are absorbed via the villi. A healthy villi is crucial for nutrient absorption.
I will stop here as processes like this keep unfolding until you excrete whatever your body doesn’t use. They key take away here is that digestion is a very complex system and although genetics, activity levels, microbiome, age and food allergies play a role, the main reason we mess it up is because our behaviors are sometimes messed up.
Software
The one running the show behind-the-scenes is the endocrine system. It is a system that communicates with your body via hormones.
A lot of times, people complain that they are always hungry, essentially whats happening is that their endocrine system is signaling ghrelin. Ghrelin is your “hungry” hormone - Whereas when people don’t feel hungry at all, leptin is the one to blame. Because leptin its secreted by fat cells, the more fat cells you have, the less hungry you are going to feel. On the other hand, the less body fat the more “hungry” you are going to feel.
Leptin also regulates energy balance and the amount of food you consume, affecting total calories.
Cholesterol fix
A key function of digestion is the detoxification process, which includes bile (made from cholesterol and bile salts). Our bodies recycle some bile salts and excretes others. Soluble fiber binds to this salts and helps us eliminate them. Since we need cholesterol to make bile salts, we can get rid of more salts by binding them to fiber. In other words, eating more fiber aids on lowering your cholesterol.
High cholesterol starts as a digestion condition, more than a heart/blood condition.
Last stop
Your poop is made up of many compounds like: dead bacteria, inorganic material, protein, dead cells etc. How often you poop depends on factors like stress, activity levels, what you eat etc.
The good bacteria, the one that is alive and thriving inside of you, is essential for fermentation inside your body. A couple of things its responsible for:
-Prevent yeast overgrowth
-Removing carcinogens
-Boosting immune system
-Preventing allergies
-Regulating inflammation, hormones and mood.
When digestion goes wrong
We all have been there - the occasional awkward fart in front of someone we just met, those are not bad. It becomes a problem when we fart all the time or whenever we feel that we have impaired breathing patterns. For some, it might be spinach, for others it might be that they are constantly stressed or they tasted a specific food. These might be a couple of problems some of us might be experiencing every one in a while, which isn't bad - But if it is repetitive, you got a problem.
-Food allergies (they have to do with your immune system and are life-threatening)
-Food intolerances (this one about lacking enzymes to digest particular foods)
-Smelly farts and messy bowel movements
-Vomiting
-Gallstones
-Diarrhea
-Leaky gut
-Etc
How to work around it
You don’t have to be a professional. You may want to work with a gastroenterologist if you don't respond to basic nutrition and lifestyle changes. Here are couple of things you may want to try:
1)Gather as much information as possible
When and how does it happen?
What are the specific symptoms?
2) Use a journal to monitor and track data. Look for patterns.
What foods are the ones causing symptoms?
How fast are you eating them?
Are you eating in a SNS state?
What happens when you avoid them?
3) Eat slowly and mindfully.
Chew. Chew. Chew.
4) Eat Whole Foods.
Avoid low fiber/high sugar/ high fat unprocessed foods.
5) Replenish deficiencies
Specifically fluid and electrolytes after vomiting or diarrhea.
6) Microbiome
Help your good bacteria do its job, specially after a period of sickness.
Add foods that contain healthy probiotics like yogurt, apple cider vinegar, kefir, kimchi etc.
The digestion process might be overwhelming as there are a lot of moving parts.The good news is that most of it is based on lifestyle, and you are absolutely in control of your lifestyle.
Hope all this info helps.
If you think someone’s digestion might be troubleshooting, send them here.
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The material on this blog is for informational purposes only. As each individual situation is unique, you should use proper discretion, in consultation with a health care practitioner, before undertaking the protocols, diet, exercises, techniques, training methods, or otherwise described herein. The author and publisher expressly disclaim responsibility for any adverse effects that may result from the use or application of the information contained herein.
