CrossFit South Bend

Today we’re going to talk about a basic intro to your digestive system, and how it actually works. You don’t need to be going into the medical field to know that this stuff is important. You should have just a basic understanding of how this stuff works, because it ends up being overall important. Not just for your digestive health, but for your overall health. So, let’s talk about how things work when you actually eat food. What happens in between when the food enters your body, and then when it exits out the backend.

First thing, your mouth. When you start eating food, your body produces saliva to basically coat that food. And, there are certain enzymes in your mouth, typically salivary amylase, which helps break down certain starches and sugars from the food that you’re eating. And then of course, chewing is going to be a huge part of that start of the digestive process. You’re basically taking whatever it is, whether it’s a steak, or roasted vegetables or something like that. Which, by itself, if you just put it into your small intestine, wouldn’t be very digestible, or absorbable in terms of extracting the nutrients out until you start this process.

So, again with your saliva. You’re kind of lubricating it essentially. And then with your teeth, you’re basically grinding it up. Then with those enzymes, and the salivary amylase, you are basically getting it ready for future things down the line. And, that active chewing starts to activate that parasympathetic nervous system. Now, technically even though I started with the mouth. Technically, even before that there’s going to be your brain. When your brain knows that you’re going to eat, it starts to secrete digestive enzymes, it starts to anticipate the food. Things like smelling your food, or anticipating your food can kind of help start that digestive process. But technically, physically, it’s going to start with the mouth.

Once we get past the mouth, the food basically goes down your esophagus, and then it gets to your stomach. A very common misconception is that digestion takes place in the stomach. That is not the case. Really what takes place in the stomach is preparation for digestion, if by digestion we mean absorption of nutrients, which actually takes place in the small intestine. What happens in the stomach? Well, that stuff that you just chewed up basically gets down there, and then assuming that your stomach acid is sufficiently acidic, which it should be. It’s typically about a PH of two, which is very acidic. Water is a seven. So, once it gets down there, that acid basically breaks a lot of that stuff down, and prepares it to be absorbed in the small intestine.

Now, another thing to realize about the stomach is that, there really isn’t that much in the way of bacteria in the stomach. We talk a lot about probiotics and stuff like that. That’s going to be much more located in things like the small intestine, and to an even greater degree, the large intestine. Isn’t to say that there isn’t some bacteria in the stomach, but it’s going to be a very, very small quantity ’cause it’s obviously a super acidic environment.

Okay, next point is really going to be the heart and soul of digestion. This is the small intestine. When we talk about leaky gut, or when we talk about a healthy gut, or we talk about are you absorbing your food. This is where the action takes place. So, your small intestine is basically where that food that you chewed up, and then was broken down by your stomach gets absorbed. And, if the acid from your stomach isn’t sufficiently acidic, then your pancreas isn’t going to release digestive enzymes to properly break down your food in your stomach. So, this whole chain is very important.

n your small intestine, there is a lining basically of single cells called, “enterocytes,” that help your body absorb nutrients from the food that you’re eating, but also keep bad stuff out. This lining is incredibly, incredibly important. It’s what allows good stuff into your body, and it’s what keeps bad stuff out.

Now again, going back to this notion of bacteria. We said that there’s a very small amount in the stomach. There’s definitely a bit more in the small intestine. But, you don’t want too much there, because then that’s going to interfere with digestion. Really where the vast majority of the bacteria is going to be, is in your large intestine. When we talk about probiotics, and healthy bacteria in the microbiome, that’s really in your large intestine. Your large intestine is basically where three main things happen. You absorb water, a lot of the compounds that your body can actually absorb like fiber and other compounds get broken down by your bacteria in your large intestine. And then, you basically, you’re preparing things to essentially exit your body.

When we talk about probiotics, healthy bacteria, there’s something like a trillion bacteria in your large intestine, and that’s where you want bacteria to be. So, it’s so important that all of these things are working together in harmony. And, if one thing is off, like if you have too much bad bacteria in your large intestine, or insufficient stomach acid in your stomach, or you’re not chewing your food in your mouth. Any one of those things can mess up digestion. And, as we’ve talked about, digestion is incredibly important for the health of your overall body.

I hope now you have a good sense of how digestion works, just a basic sense. And, in the next few videos we’ll talk even more in depth about how this stuff works. All right guys, thanks so much for tuning in. We’ll see you next time.