Aug. 28. 2015
McKel Hill

McKel Hill

MS, RDN, LDN, Dietitian

It’s been awhile since I’ve added to The Basics and I’m glad it’s making a comeback with this topic, Digestion! Digestion is one of my absolute favorite topics to talk about yet it’s also incredibly dense and I could probably go on for 10 blog posts or more. Hence why writing these in The Basics gets tricky for me, knowing how to make it easy for you to understand and take home points that you can actually utilize in your life. Okay, let’s break this down!

 It’s all about, gut health.

In a perfect world, we would eat our food, it would digest well with little to no side effects like bloating, diarrhea, constipation, cramps, etc.; and our bodies would be able to pull out all the nutrients from the food and utilize it as intended. But unfortunately, it’s not a perfect world and our digestive systems go through so much “wear and tear” over the years that it affects how efficient our digestive system operates and how our bodies absorb key nutrients from our delicious and healthy food. Things like hormonal shifts, stress in our life (oh goodness I could write an entire blog post about how stress affects our digestion!), activity, genetics, food intolerances (if any), vitamin and mineral status, metabolism, thyroid health, chronic diseases/any illness, medication use, supplement use, sleep, environmental toxins/everyday exposure, antibiotic use as infants, and of course what we put in our bodies with food; all of these factors have an impact on our digestion. Before we cover things we can control and ways to make our digestion better, we need to understand the nitty-gritty of digestion.

What is the digestive system and what organs make it up? Digestion is the act of consuming food, breaking down food, processing, and utilizing it for energy. There are a couple ways food is digestion, one by mechanical digestion (think of when you chew your food where it’s physically being broken up into tiny little pieces); secondly by chemical digestion where food is broken down into even smaller molecules with the help of digestive enzymes. Hooray for enzymes! Enzymes actually start at the first site of digestion, our mouth, with saliva. Saliva contains an enzyme called Amylase which helps start the chemical process of breaking down the food while our teeth start the mechanical. I’m going to stop us right here- this friends, is why chewing your food well is VITAL for good digestion. The quicker we eat, the larger food particles enter our stomachs, the more digestive enzymes and energy is required for our bodies to break the food down; so why not help optimize this at the first line and first step? Right!

Next, food goes through your esophagus then reaches our stomachs where chemical digestion, gastric juices, start to breakdown our food- mostly the gastric juice is made up of pepsin and hydrochloric acid. I know, acid in our gut sounds scary right, but it’s a good thing! Our bodies must have enough acid to help breakdown food and proteins in our digestive system; actually those who suffer from low HCL level can actually experience higher incidences of GERD or reflux issues. Fun fact, our bodies can secret about 2 liters of HCL a day! Our body is incredibly smart though, we have enough mucus lining out stomach to protect that same acid we need, from damaging our own organs- it’s genius! So, while we have acid working on breaking down the food, we also still have mechanical digestion happening through a process called peristalsis (perry-stall-sis) which makes the muscles in the stomach wall contract and release to mix up the food and enzymes. Here’s a little video about how it works. After the food has been chemically and mechanically broken down, which can vary in time depending on how much food you eat and the variety but around 1-2 hours, it goes into the small intestine. The small intestine again, breaks down the food and also is a time where many vital nutrients are absorbed, little finger-like projections called villi and microvilli provide a HUGE surface area for our bodies to absorb these molecules from food and get into our blood vessels of the intestinal wall. This is how awesome the small intestine is: it’s about 22 feet long and 1 inch in diameter, and the surface area is about the size of a 2700 square foot tennis court! This is possible because the small intestine not only has folds, but on those folds are villi, and on those little villi are microvilli. Layers on layers on layers all to help you absorb food.

Our liver and pancreas get in on a little digestion action too- the liver produces bile, which is carried into the small intestine by a bile duct, then the pancreas secretes pancreatic juices and enzymes that aid in digestion as well. Lastly, after the food has been broken down and passed through the small intestine, the large intestine absorbs all remaining nutrients and mostly water; this is how stool is formed and then it passes out of our bodies.

  1. Carbohydrates: require amylase enzymes — broken down into simple sugars, glucose molecules
  2. Fats: require lipase enzymes — broken down into monoglycerides and fatty acids that involve emulsification, micelles, and chylomicrons
  3. Proteins: require pepsin enzymes — broken down into amino acids

I’m a visual learner and have a hunch many of you would enjoy “seeing” digestion in full action, so here’s an easy-to-navigate iconographic below to help you visualize how it all works, above. Basically the route of digestion is: mouth → esophagus → stomach → small intestine (pancreas and gallbladder are involved here as well) → large intestine → colon

There’s a saying I always teach and also practice myself as much as possible “Chew your liquids and swallow your solids”; meaning chew your food thoroughly enough that it’s to a puree texture and then swallow and swish around liquids in your mouth so you’re not just guzzling smoothies, juices, even water without activating the first part of digestion in the mouth from your saliva. Now that you understand both mechanical and chemical digestion with digestive enzymes, this makes sense, right?! I say this often to clients, you could eat the healthiest diet, have everything in your health “aligned”, yet if your digestive system is under stress and isn’t functioning properly- unfortunately you won’t be able to utilize and get the optimal/most out of what you just ate. So how do you optimize your digestion? It takes a lot of time, patience, and playing guinea pig to get to the bottom of exactly how your digestive system is, what helps and what “hurts’ it + some specific protocol I share with my clients. I’ll be sharing some of the tips in part II or if you have immediate questions you can always contact me for a consult here and we’ll get started.


Do I need to take digestive enzymes? 


Digestive enzymes in the form of a supplement can be quite helpful for those of you who need a little boost. For example, many can’t digest beans and legumes very well and there are many supplements on the market that help break down polysaccharides. Fun fact, there are some foods that contain natural digestive enzymes that are more “powerful” than most other whole foods like pineapple and papaya! Do you need to take digestive enzymes, no; but some cases it can help alleviate gas and bloating. Always check with your doc.

Other ‘Basics’ you may enjoy reading and learning about:

Part II will cover ways to improve your digestion, how to eliminate foods that irritate your stomach/digestive system, and any other questions that you all leave in the comment section below!
xx McKel

Resources: good ole’ textbooks from school or otherwise linked.