Trust Your Gut (literally)
You, the Physician
When you improve your digestion, you improve your health, immune function, physique, and feelings of wellness and lightness. You’re also taking an active role in preventing disease.
Āyurveda, the ancient healing system of India, lends its 5,000 years’ wisdom to us where it comes to leading a healthy, vibrant, long life. In this system, based on the five elements in nature, agni[1]—the fire element—governs digestion and metabolism. It is because of agni that our bodies transform food, aka life energy, into absorbable material that it can use. A robust agni is responsible for good digestion, heightened immunity, and an overall feeling of wellness. But low agni, a diminished digestive fire, is the root cause of all disease (see āma discussion below). That may sound like a wild claim, but think about it: how many diseases in the US are linked to the foods we eat? The CDC names our top killers, and a number of those making up the top-10 are food- and diet-related. Think about how you feel after you eat a bunch of processed food: probably heavy, lethargic, gassy, bloated. Maybe your skin breaks out after eating certain foods. Maybe you feel irritated or depressed. Maybe you’re dealing with high cholesterol or hypoglycemia.
It's easy for people to overlook the mundane, those little choices we make every single day, and discount the effect that food has on our health. We’ve been trained by society and big pharma to look outside ourselves for good health. We’re taught to go to the doctor when we don’t feel well (because the doctor will fix us with a pill) or to do what the billboards suggest (“milk, it does the body good” must be right because the message is everywhere) or just excuse it as a symptom of aging, instead of checking in with our bodies. If we get bloated or experience acid indigestion after a meal, we’ll go to the doctor for a prescription or pharmacy for an antacid instead of looking at what’s causing the problem and nipping it in the bud. Get bloated or congested after dairy? Try a non-dairy alternative. Have indigestion? Perhaps take out the coffee, red wine, and spicy food for a bit and see if that fixes things. If we address the signs our bodies are showing us early enough, it’s quite possible we can prevent serious disease from developing.
Our incredible bodies digest food for us all day, every day, yet so many of us are clueless as to how it all works. This disconnect leads us to ignore the subtle—or glaring signs—our bodies give us about how it’s going in there. Most of us know a lot about a lot of things, but so many have no idea about what’s happening within our bodies—the most intimate relationship we can have! Recently, I was speaking to a woman whose GI doctor had ordered a colonoscopy and reported back some concerns. When I spoke to her about her diet and digestion, she laughed me off: “It’s my colon, not my digestive tract! It has nothing to do with food!” Um… I believe this is a good place to start…
Note: this is a long one, so if you want to jump over biology and get straight to what you can do about your own digestion, scroll down past the diagram.
The Digestive System
We were taught about the digestive system early in our school days, but let’s take a refresher course. The digestive system begins in the mouth, then twists and turns through, and interacts with, numerous organs and canals (i.e., esophagus, stomach, pancreas, liver, gallbladder, intestines, colon) until it ends at the anus. The entire digestive tract is roughly 30 feet long and has its own nervous system (called the enteric nervous system) that controls digestion without us ever having to think about it. The GI system is truly a marvel of biology and has a mind of its own! Let’s take a look at how it all works:
Stages of Digestion
Depending on who’s teaching, the digestive process can be broken down into 3 to 7 stages. Essentially, we’re all saying the same thing, just taking different approaches to describing the same process. Āyurveda states that there are 6 stages of digestion, from the mechanical process that starts in the mouth through the absorption process in the small intestine. Since this was my introduction to medicine and the model I studied, I’ll take that approach. A more Western description can be found here.
Our digestive process actually begins before we ingest any food. When we smell the aroma of food, our mouths start salivating, preparing for what’s to come. The length of time a meal takes to digest will vary, depending on the person and the makeup of the meal, but it takes roughly 6 hours for a meal to move from the mouth down through the small intestine, where the smaller molecules are absorbed through the intestinal walls and into the bloodstream. Food moves through the large intestine more slowly, usually taking another 16-36 hours, where the last absorption of minerals and water occurs and feces begins to accumulate. Finally, any undigested food particles are stored in the rectum as feces, until it’s time for elimination. Depending on the source (and a whole host of personal factors) the entire process of digesting a meal—from mouth to anus—can take anywhere from 10-73 hours. For most of us, that’s an average of about 2 days transit time. Want to test this out? Eat a bunch of red beets and wait and see what happens!
* Note: I break this down into 6 stages, with one hour per stage. This is a rough estimate and will depend on a number of factors (i.e., amount and type of food, metabolism, genetics, etc.). But for ease of understanding, each stage is 1 hour here. Just know that can vary a bit from person to person.
Stage 1
The first hour of digestion begins in the mouth with chewing and tasting food. Chewing mechanically breaks down food for easier digestion and better absorption. The enzyme amylase in saliva starts breaking down complex carbohydrates while food is still in the mouth. Saliva also assists with our sense of taste. Tasting food alerts digestive organs to prepare for what’s headed their way. For example, when you eat something sweet, the pancreas gets the message to start pumping out insulin to balance the blood sugar. The bitter taste will alert the stomach to produce acids that can counter toxins (bitter taste is common with poisons, though it certainly can be attached to a healthy food as well!).
Once food is chewed and swallowed, it passes by the pharynx (the protective structure that ensures food moves toward the esophagus and air moves toward the larynx/trachea), down the esophagus, and into the stomach. Once the stomach has food, it starts the mechanical process of churning, breaking food down into a more liquid form. Simple sugars are immediately absorbed through the walls of the stomach and into the system for quick energy (why we can get a little crazy immediately after eating sugary snacks).
Stage 2
The second hour of digestion continues in the stomach. Here, hydrochloric acid (HCl) is secreted, along with gastrin and pepsin to aid in the digestion of proteins and fats. This chemical digestion further breaks food down before leaving the stomach. At this point, the chyme, or liquified foodstuff, is very acidic.
Stage 3
The third hour of digestion begins when the pyloric valve (the sphincter at the bottom of the stomach) opens and food moves into the small intestine, beginning its journey through 22-25 feet of this muscular tube. 90% of food absorption occurs in the small intestine.
Once food reaches the duodenum, the uppermost (and shortest, at 9-11”) C-shaped part of the small intestine, the hormones secretin and cholecystokinin (CCK)[2] are released to stimulate the pancreas to secrete enzymes and the liver/gallbladder to secrete bile in order to alkalinize the acidic chyme so it doesn’t corrode the small intestine. The enzymes and bile aid in further breakdown of carbohydrates (via amylase), proteins (via protease), and fats (via lipase) into glucose, amino acids, and fatty acids, respectively, so the body can better absorb nutrients.
Stage 4
The fourth hour of digestion occurs in the jejunum, the middle part of the small intestine that spans roughly 8 feet. Here, carbohydrates, proteins, and fats continue digesting and peristalsis, the wavelike contraction and relaxation of muscles throughout the GI tract, moves the chyme rapidly through the intestines. Most digestion and absorption takes place in the jejunum. Villi (tiny fingerlike projections) and microvilli (fuzzy cells on the villi) in the intestinal wall increase the surface area to aid in better absorption of nutrients into bloodstream.
*Note: there’s no hard line where the sections of the small intestine begin/end, but it helps to view them as distinct sections.
Stage 5
The fifth hour of digestion begins when the chyme enters the ilium, the lowermost—and longest (roughly 11-12 feet)—part of the small intestine. This is where the rapid absorption of vitamins, minerals, and macronutrients occurs. Peristalsis continues to move the chyme onwards towards the large intestine. The stomach begins to feel lighter, and you might notice the slight tug of an appetite coming on.
Stage 6
The sixth hour of digestion happens when the ileocecal valve (the sphincter separating the small and large intestines) opens and chyme moves into the cecum, a pouch at the top of the large intestine. The cecum is known as the “second stomach,” as food is stored here for a bit.
Once the initial 6 stages of digestion are complete, the remaining food moves into the large intestine, where the final absorption of minerals and fluids occurs. Here, feces is formed and moves toward the rectum via peristalsis until it’s time to evacuate, a process that can take around 16-36 hours. The large intestine is roughly 5 feet long.
Mouth, chewing
Stomach, churning, enzymes, acids
Duodenum, enzymes, bile
Jejunum, absorption
Ilium, more absorption
Cecum, then large intestine to rectum
The journey of food through the GI tract.
It takes, on average, 2 days from end-to-end.
Signs Your Digestive System Needs Some TLC
It amazes me when people tell me that digestive symptoms are “normal,” and that they’ve just learned to live with them. Indigestion is not normal. We should feel energized, light, and comfortable after our meals—anything else is the body’s reaction to what we’re feeding it. We should be having regular bowel movements—at least one per day. These signs are here for us to pay attention to and start an inquiry into our digestion… and overall health.
This can be approached by considering the five elements in nature. Oftentimes a person’s issues will be more closely relate to a specific element-combination than others. That is, related to their individual constitution, or dosha. For example, one person might be prone to more airy symptoms: gas, bloating, or constipation (ether-air) after eating, while another might experience the fiery symptoms of GERD, heartburn, acid indigestion, or colitis (fire-water), and yet another could experience the watery symptoms of congestion, edema, or a sense of heaviness after meals (water-earth). See if you can recognize your digestive type:
Vāta (Ether-Air)
Irregular, erratic digestion.
Qualities: Cold, dry, light, mobile, subtle
Constipation
Variable appetite: strong at times, absent at others
Gas
Bloating
Gut gurgling
Colicky pain
IBS (constipation <-> diarrhea)
Pitta (Fire-Water)
Sharp, burning digestion.
Qualities: Hot, sharp, liquid, oily
Diarrhea or loose stools
Sharp appetite (“hangry”)
Burning sensations
Acid indigestion
GERD
Inflammation
Colitis
Hot flashes
Kapha (Water-Earth)
Slow, dull digestion.
Qualities: heavy, slow, cold, sticky
Stinky bowel movements that sink and streak the toilet
No or very little appetite
Heavy stomach
White coating on the tongue
Symptoms of cold
Congestion
Allergies
Excess mucous
A Note on Indigestion/Āma:
If the colon is coated with undigested, unabsorbed foodstuff, it affects what nutrients might pass through and be absorbed by the body. Āyurveda calls this coating āma—undigested food (aka unmetabolized chyle, in Western terms) when, not metabolized or eliminated, creates a sticky toxic substance that accumulates in the colon. Āyurveda considers āma the root cause of disease, which is why food and healthy digestion is given so much consideration in this healing system.
How do you know if you have āma? Stick out your tongue. Is there a gross white coating on it (grab a spoon or tongue scraper and make a couple passes across your tongue and see what comes off)? That’s a sign of āma. Feeling sluggish, have stinky-sticky-sinking poop, lack true appetite, or have horrible smelling breath? Āma. If your system’s bogged down and you’re suffering for it, popping vitamins and supplements isn’t going to do the trick—there’s a good chance they won’t be absorbed, no matter what you ingest.[3] There is no substitute, no pill, that can take the place of a good diet and solid eating habits. Āma is best addressed by cleaning up your food intake, stimulating your appetite, and addressing those eating habits. Your system can further be supported with certain spices and herbs once you’ve first addressed the diet.
There is no substitute, no pill, that can take the place of a good diet and solid eating habits.
Signs of Good Digestion
Daily, complete bowel movements (shaped like a well-formed banana, very little smell)
Previous meal has been fully digested, with no lingering feelings of indigestion
Healthy appetite is present
No burping or gas. If there is a burp, there is no taste or smell to it
Body and mind are energized after a meal
Causes of Indigestion
Eating too soon after a meal/snacking between meals
Eating when no appetite
Eating too much at one time
Emotional eating
Drinking too much liquid with food
Drinking cold drinks
Eating when feeling constipated or with other digestive issues
Eating leftovers, frozen food, fast food, or packaged food
Incompatible food combining
Stress. Body in sympathetic mode and energy goes to survival vs. digestion
Not chewing properly before swallowing/eating too quickly
Digestive Aids
There are numerous pills and tablets and herbs that can assist with better digestion—or at least mask the problem while we continue about our days. But I like Āyurveda’s approach, where we look at what and how we’re eating to identify the cause of our dis-ease. Once identified, we remove the cause. With a little time, many digestive ailments can clear up on their own. Āyurveda asks us: Can you make some improvements in your behavior and choices before heading to the pharmacy? If you’ve done all you can do and are still in need of support, then try some spices or natural herbs. Still not working? Only then resort to medication (of course, listen to your doctor and your body before taking my word for it.).
Conclusion—What to Do?
Hopefully this discussion helps you better understand the digestive process and the effects your diet and lifestyle can have on your digestion and overall health. We took a quick journey through the GI tract, the phases of digestion, and some common ailments associated with eating. Now that you have this awareness, and perhaps have identified a couple issues related to your own body, here are some ideas you can try. As always, if you have any concerns about your health, discuss those with your doctor before making any major changes—especially if medication is involved. I wouldn’t advise anyone to stop or change their medication without the guidance of a physician.
Here are some simple things to try to get your digestion back on track:
Eat only when the body sends signals of hunger.
Learn to distinguish between actual and emotional hunger. Not sure? If you feel pulled to eat, but don’t necessarily feel hungry, take a walk and some sips of water before eating. If you’re still hungry—that’s your body. If it eases, then perhaps it was emotional hunger or thirst.
Take smaller bites and focus on chewing food completely before swallowing or adding another bite. Slow down.
Don’t eat to complete fullness. Your resting stomach is roughly the size of your tightly-closed fist (but can stretch up to 75 times its empty volume!). You likely don’t need as much as you’re stuffing down the hatch.
Use good judgment when dining out and eating what’s on the plate (often, it’s 2-3 servings!). You can share a dish with a friend or portion out 1/2 or 1/3 of your meal and package up the rest. Better yet: learn to cook and minimize eating out!
Wait until a meal is fully digested before eating again (reflect back on all those enzymes and processes that kick in at each stage—there’s a time and place for them, and it’s rude to ask them to work overtime!). Pay attention to signs of hunger for guidance. If you ate a solid meal, you likely won’t need a snack between meals.
Preparation is prevention: learn to plan meals and prep food in advance
For optimal digestion, try filling your belly with: 1/3 food, 1/3 liquid, 1/3 air
Avoid certain combinations of incompatible foods, as their different qualities affect digestion times, enzymes, and acids (e.g., fruit digests almost immediately, but meat or dairy can take much longer, leaving the fruit to ferment in the stomach while it waits for the other to catch up). This may come as a shocker, since many diets and nutrition references (even doctors) combine a lot of these foods (perhaps a big contributing factor as to why digestive issues are so widespread??). A little experimentation will give you direct feedback as to whether these combinations adversely affect your digestion:
Milk with bananas
Dairy with eggs or fruit or fish
Melons with anything (best eaten on their own)
Honey with grains (avoid cooked honey entirely)
Nightshades (potatoes, tomatoes, eggplant) with dairy
Raw foods with cooked foods
There are numerous other steps that can be taken to improve your digestion, and your specific needs can be addressed in a one-on-one consultation. An important first step to better health is understanding your body and how it works, then identifying which habits you want to address to improve your health. Once you’ve increased your awareness, try removing the cause and see if that eases your symptoms. From there, you’ll set the foundation and get in the groove of listening to your body and taking charge of your health. True healing is an inside job—nobody (not even the best doctor in the world) can do it better than you.
***
[1] Fun fact: the English word “ignite” comes from the Sanskrit word “agni”: “that which ignites/fire”
[2] Fun fact: cholecystokinin (CCK) means “move the gallbladder”
[3] That is, if the supplements are of superb-quality, which are hard to find. Many, many supplements don’t contain what they say they contain—and some of what they don’t list on the label. If you’re taking supplements, be extra diligent with your research.
Resources
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