To maintain a healthy brain, we need a healthy gut, and to maintain a healthy gut, we need a healthy brain!

Q: From a functional medicine perspective, there is big emphasis on the gut-brain connection, and I'm wondering, where do you begin that conversation with your patients when they first come to you?

Yeah, it's challenging, right, because people come in with a gut problem and they're like, “I'm not coming in for my brain. Why are you looking at my brain?” 

Well the last 10 years, probably the biggest area of research is the gut-brain access or the brain-gut access.  Whatever you look at; your brain usually has some sort of influence over it. So, when you look at The Brainstem: the brainstem out in the middle and the lower part of it is where the nucleus lies that controls what's called your Vagus Nerve. Okay, the Vagus nerve, Vagus in Latin means “the wanderer,” the Vagabond, means it goes everywhere. Vagus nerve is a rest and digest, a parasympathetic nerve. It goes into your heart to control and kind of calm down your heartbeat when you're in the fight-or-flight stage. Fight-or-flight tips the scale, you might have a higher heart rate. Parasympathetic is the rest and digest, which, Vagus nerve is a rest and digest, a parasympathetic nerve. 

It can aid in proper digestion it can calm things down this is where deep breathing, meditation, Pilates, yoga, doing the things you enjoy to do, taking time at the dinner table, not being in a hurry, all those things are very parasympathetic things, right, very healing, very restful things that can really, really do a lot of good things and just making us, you know, heal a little bit quicker. The Vagus controls a lot of those functions and when the Vagus works correctly, 

one: it increases your digestive enzyme production naturally, 

two: it moves blood flow to the area, right, to promote healing and to absorb the nutrients and all that kind of stuff, 

three: it will also increase motility, so in the constipated patients, like, if you don't get that nerve signal to the smooth muscle, the gut, it can't contract the gut and squeeze behind that, you know, fecal matter and move that bowel movement along.

Another one is also increasing gall bladder contraction to squeeze out that bile to break down your fats. It will even go into the gut lining and basically make those tight junctions be less vulnerable to leaky gut. 

The last one is the ileocecal valve. Ileocecal valve is where the last part of the small intestine joins the first part of the large intestine, that transition segment. There's a valve there and most of the research shows that the Vagus nerve goes right into that valve to keep it nice and firm and taut and toned. And the reason why is because when you look at conditions like SIBO, Small Intestinal Bacterial Overgrowth, okay, it's more of a translocation, or movement, of the bacteria that's supposed to stay in the colon, the large intestine, and it ends up getting through that valve and traveling up into the small intestine, and then when the bacteria is there where it's not supposed to be, then it starts to gobble away at your food that's not digested yet and it releases a gas as a consequence. Gas has nowhere to go and then it distends or bloats your gut. Okay, so the Vagus controls a lot of those functions and when the Vagus works correctly and it goes into the proximal 2/3 of the gut, which means the stomach, the small intestine, even parts of the large intestines, the beginning parts, and when it works properly it does a bunch of really good things in just making us you know a little bit quicker. 

If someone had a concussion, a traumatic brain injury, things like that, could that influence gut? And we know that's true because they've done studies on giving rats concussions, sounds kind of mean, but they study a lot of these things on rats and they gave them a concussion. They measured what happens at the lining of the gut, the level of the gut, and all the rats got leaky gut after the concussion. I can't remember how many hours, but within a certain amount of hours they got leaky gut. And then what they did is they take the same parameters, they gave the same amount of force and everything with a different population of rats, and then they measured the gut, but the only difference is they put a little electrode on the Vagus nerve and they kept the Vagus nerve firing the whole time, even after the concussion, and they ended the study because there was no leaky gut. So, it shows you that the brain has a tremendous influence over gut function.

That’s fascinating. If the parasympathetic system isn't triggered the right way, then definitely there will be issues and multiple issues that we’ll experience. 

Q: The thing that I still need clarification on is, if my gut is imbalanced, if there is dysbiosis in the gut, how does that slow my parasympathetic system down? Why does it affect my brain?

Yeah so there’s communication from the brain to the gut and the gut to the brain, the brain to the gut, the gut to the brain, right, back and forth, back and forth. So, if I have dysbiosis in my gut, which is likely to produce some sort of inflammatory type of mechanism. When you look at, like, the world of Parkinson's research, I think it was the Michael J. Fox Institute or Foundation, they found, man Parkinson's patients, they have this certain strain of bacteria in the GI tract that travels up into the brain stem and then causes a problem. Now, one characteristic of a lot of Parkinson's patients is they have constipation for a long time prior to the diagnosis. Okay, so you start to look at that as like the brain-gut kind of connection there.

Calprotectin is the measure that they use in the stool test to look at just inflammation. It goes really, really high, you get more suspicious of, like, inflammatory bowel diseases like Crohn's, Ulcerative Colitis, things like that. There's other things that are more sub-clinical, meaning the patient could have normal calprotectin but maybe they have this huge dysbiosis, right, where they have way too many of the opportunistic bad bacteria and they don't have enough of the beneficial bacteria and they have this huge, you know, ratio problem. And so, when you look at that, if that creates some sort of inflammation, that can travel up and cause, you know, a barrier breach in the blood-brain barrier, right, same lining is the gastrointestinal barrier. When you have, like, a neurological consequence to it, okay, then that can then affect the gut more negatively, right? It's just like, this perpetual cycle that just goes on and on and on. Sometimes, you know, the gut causes the brain problem, brain causes the gut problem, things like that too. But you have to look at both of them and figure out, kind of, like, how one can negatively affect the other and what one might be primary, what one might be secondary as a result. 

Bottom Line: 

To maintain a healthy brain, we need a healthy gut, and to maintain a healthy gut, we need a healthy brain!