Digestion: From Brain to Bowl

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Digestion: From Brain to Bowl | stephgaudreau.com guts.png

Steph’s note: Please welcome my guest blogger Heather from Just Love Your Guts. Heather’s a true personification of a healthy, balanced lifestyle and she blogs about nutrient-dense recipes and wellness. She’s got a positive outlook and infectious enthusiasm. In addition, Heather’s a wellness coach, personal trainer and is currently studying for her Nutritional Therapy certification. I know you’ll find her post super-informative and entertaining, too. Take it away, Heather!

“Digestion is the breakdown of food into smaller components that can be more easily absorbed and assimilated by the body.” —from the all-knowing Wikipedia

Well, that’s a pretty succinct definition of digestion, don’t you think? But how does it work?  Why does it matter? What can we do to avoid digestive dysfunction?

Let’s take a walk down the digestive road, and I’ll try to break it down for you. (Get it??)

How does it work?

Think About It!

Digestion starts at the top and works its way down. Literally. The process actually begins in your brain, as soon as you even think about food. When the thought of food enters your mind, or you see it, smell it, taste it, your salivary glands kick into action and your stomach gets the signal to prepare for some serious nommage.

Chew Before You Swallow!

So, your salivary glands are now pumping out saliva. Saliva serves a huge purpose. (It’s not just for spit wads.) 99.5% of it is water and from the first bite, it moistens the food and lubricates the esophagus—the tube that leads food from your mouth to your belly—making it easy to swallow and transport food to the stomach. The other 0.5% contains enzymes that begin to chemically breakdown food—specifically carbohydrates—while it’s still in your mouth, before you even swallow it. (Am I a nerd because I think that’s totally cool? Maybe, but I’m alright with that. (Steph’s note: No Heather, you’re not a nerd. It’s amazing.) That initial breakdown of food in the mouth is a pretty crucial step, which is why it’s so important to adequately chew your food!  Chewing your food 20 to 30 times per bite not only begins the mechanical breakdown process, but it gives those enzymes sufficient time to start the breakdown on a chemical level. That way, when when the food is swallowed and travels to the stomach, it is prepped and ready for the next stage.

Down The Hatch!

You’ve chewed and swallowed your food. Now, you’ve got a pretty awesome blob of mush traveling down your esophagus where it will pass through the lower esophageal sphincter (LES) and into the stomach. The LES has a really important job. (Okay, every job in the digestive process is important.) The LES lets food pass into the stomach, and it’s designed to be a one-way valve. The everyday responsibility of the LES is to allow food into the stomach and not let anything back up into the esophagus. There are exceptions of course, like when something enters your stomach that your body wants OUT. Then it becomes somewhat of an “emergency exit” and can be forced open to allow food back up & out (a.k.a. hurling). For now, we’ll assume you ate some awesome grass-fed, organic, nutrient-dense food that your belly is happily accepting.

Your Stomach:  It’s SUPPOSED to be Acidic!

So now this awesome grass-fed organic mushy blob has made it to your stomach. (As much as I love my name for it, that blob of food is called a bolus.) When the bolus arrives in the stomach, the ideal environment should be VERY acidic. Having the proper level of acidity (pH) in the stomach is crucial for a host of different reasons; here’s just a few:

  • Stomach acid (hydrochloric acid) disinfects the bolus and any bad bacteria or contaminants that may have been in or on your food, thus reducing your chance of food poisoning or bacterial infections.
  • Proper stomach acid levels, along with churning actions of the stomach muscles, are necessary for the further breakdown of the bolus, turning it into an even more liquidy mushy blob called chyme.
  • The pH of the chyme determines when it will be allowed to leave the stomach and enter the small intestine. If the environment is not acidic enough, it will sit in your stomach for too long and become a veritable breeding ground for bacteria. As bacteria feed on the poorly digested food, they can give off gas and create upward pressure on the LES. If the LES is forced open by this pressure and stomach acid (even a teeny tiny bit) is allowed to creep up into the esophagus, you get the burning sensation associated with heartburn or indigestion. See, the stomach is supposed to be an acidic environment, but the esophagus?  Not so much. Heartburn is a case of a little bit of acid in the wrong place, not too much acid in general—despite what the antacid commercials claim.

Assuming we are dealing with a healthy acidic stomach environment, let’s move on down the digestive road. When the pH of the chyme is right, a valve at the bottom of the stomach, called the pyloric valve, allows the chyme to slowly enter the small intestine. Upon initial entry, the acidic chyme triggers the release of multiple digestive juices. The liver and gallbladder produce and release bile, a substance that emulsifies fats. The pancreas releases digestive enzymes that begin to break down the food into nutrients we can actually absorb and use. It also releases sodium bicarbonate, which raises the pH of the chyme to a more neutral level for its trip to the small intestine.

Gimme Those Nutrients! (Or, if you’re more mature than I am, “Absorption”.)

So here we are, the chyme is movin’ on down through the small intestine. In the lining of the small intestine, there are these microscopic little finger-like things, called villi & microvilli. They’re responsible for absorbing the nutrients in our food so we can use them. Imagine this: The chyme is Justin Bieber and the intestinal lining is the red carpet. The villi are a bunch of 14-year-old girls flanking the red carpet, collecting autographs, photos, hugs and high-fives (nutrients) from the Biebs himself. (Did I seriously just use a Justin Bieber analogy to explain nutrient absorption? Yikes.) These nutrients (a.k.a. digestive Bieber hugs) then get passed on to the bloodstream where they can be used for energy and various other metabolic functions.

Solid, man.

So, what comes next? Through the gut lining, we’ve collected, absorbed and assimilated the nutrients from the food, so are we done with it? Well, it’s still liquidy chyme at this point. Key phrase there is, it’s still liquidy. How do I put this politely? I don’t know about you but in my book, if it’s still liquidy, we’re not “done with it”. It’s got one last stretch of digestive road to travel before we’re done with it.

This last stretch of road is the large intestine. Most of the large intestine is also called the colon. While most of our nutrient absorption occurs in the small intestine, the colon absorbs a significant amount of water along with any remaining available nutrients. The process of absorption in the colon is a slow process and can take anywhere from 3 to 10 hours. You may be putting this together in your head already but with all that water absorption, the chyme is now losing excess liquid and becomes the semisolid superstar we all know and love to talk about, poop.

I’m gonna guess by now, you’ve all figured out how this story ends, right? I’ll spare you the details but in the interest of landing this plane, we have made it to the bowl! (The crowd goes wild.) As long winded as I can be, this description is a pretty general explanation of what happens from the minute we think about food, eat it, get all the goodness we can out of it and eliminate the leftovers.

But, why is digestive health so important?

I’ve taken the time to describe this process from start to finish, because it is so important. It really goes beyond just having a pleasant experience in the bathroom. (Although, that is a perk). A healthy and fully functioning digestive system is foundational to overall health. When we have optimal digestive function, we are able to absorb every last possible nutrient we can get out of our food. After all, nutrients are the true prize we’re after when we eat a meal—or at least, they should be. Nutrients feed our cells, tissues, bones, muscles and organs…everything.

Without proper digestion and assimilation of nutrients, things can really start to fall apart.  We can become deficient in vitamins, minerals and essential fatty acids. These deficiencies can lead to an infinite number of conditions, many of which we’e probably never guess had anything to do with digestion such as headaches, allergies and even depression). I could write an entire post about what can go wrong when our digestion suffers, but let’s just say that if you’re suffering from any condition, exploring your digestive health could be the first step on your road to recovery.

What can you do, right this minute, to improve digestion?

There are a few simple steps to take, as soon as the next bite of food, to get digestion working more efficiently.

Chill out.

You’ve may have heard the term “fight or flight” used to describe the state our bodies go into during a response to stress. That reaction is governed by the sympathetic nervous system and is incredibly useful in times of distress. It sends signals and directs energy to our muscles (away from our digestive organs) so that we can quickly react in a stressful situation.

But what about “rest and digest”? That state is governed by the parasympathetic nervous system and is the state we need to be in before we eat. In the rest & digest state, attention is directed toward the digestive system and our bodies will focus on producing the necessary substances to adequately digest food. If we don’t slow down and allow our bodies to switch into a parasympathetic state before eating, we are sending food into bellies that aren’t prepared to receive it. This can cause digestive upset and malabsorption of nutrients.

Be thankful.

Allow yourself to feel grateful for the nourishment in front of you. Take a few deep breaths and a moment to imagine the health that your food is going to promote in your body.  That may sound like a bunch of malarkey, but I promise you, it’s not. This act of gratitude can quickly adjust our mindsets and in turn, better prepare our bodies to accept and digest food appropriately.

Chew your food.

I touched on this in the beginning and I’ll say it again because it’s that important. From my own experience, slowing down and chewing at least 20 times makes noticeable changes in digestion. Swallowing food that hasn’t been chewed properly can lead to digestive discomfort and less-than-ideal nutrient absorption.

Other ways to improve digestion include eliminating potentially irritating foods like processed grains and refined sugars, sipping a little apple cider vinegar or lemon water before meals, and/or natural supplementation. But simple steps like stressing less and chewing more might be all you need!

So I leave you with these words to sum up:  Breathe, be grateful, chew your food and just love your guts!

Connect with Heather and Just Love Your Guts on social media: Facebook, Instagram and Twitter.

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Digestion: From Brain to Bowl | stephgaudreau.com

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