The Gut-Brain Connection: How To Feed Your Brain
If there was ever a call for "digestive health," this is it!
Yes, it's true. Your gut is considered your "second brain."
There is no denying it anymore.
And because of the new scientific discoveries about the vagus nerve, the enteric nervous system, and the amazing influence your gut microbes can have on all aspects of your health (including that of your brain), it's no wonder that what you eat feeds not only your body but can directly affect your brain.
What exactly is the "gut-brain connection?”
The gut-brain connection is a very complex system or network that allows direct communication between our gut and brain. And to be honest, we still have a lot more to learn about it.
But here’s what we do know. There seem to be multiple components that work together to create the health of our gut and brain. These components include:
The vagus nerve that links the gut directly to the brain
The “enteric nervous system” (A.K.A. “second brain”) that helps the complex intricacies of digestion flow with little to no involvement from the actual brain
The massive amount of neurotransmitters produced by the gut
The huge part of the immune system that is in the gut, but can travel throughout the body, and
The interactions and messages sent by the gut microbes.
In short, it is a complex and complicated web - and utterly amazing, if you ask me.
Let’s take a closer look at each of these areas.
The Vagus nerve
There is a special nerve that runs directly from the gut to the brain. It happens to be the longest nerve in the human body, and is referred to as the “vagus nerve,” the “tenth cranial nerve” or “wandering nerve.”
Why “wandering?” Because it meanders throughout your body, connecting all organs to the master network of the brain. It acts as a communication superhighway, transmitting messages between your gut and brain through its “neuro-endocrino-immunological” connections.
Translation? The vagus nerve links the gastrointestinal tract and the brain.
It can also be thought of as the gut-brain axis. As such, it has many important functions, including regulating gut health and balancing energy within the body.
It is also a unique nerve, as messages can be sent along this superhighway in either direction. But can you guess which direction 90% of the transmission is sent?
Not from your brain to your gut (which is what we used to think), but from your gut up to your brain!
That means the health of your gut plays a greater role in the health of your brain than we realized. So, to feed your brain right, you must first start by feeding your gut!
The enteric nervous system and neurotransmitters
Would you believe me if I told you that your gut has more neurons than your spinal cord?
I knew you would! This is why your gut is also referred to as your "second brain” - the enteric nervous system.
If you think about it for a moment, controlling the complex process of digestion (including the breaking down of food, absorption of nutrients, and the expulsion of wastes) should probably be done pretty “smartly”- don't you think?
The nerves in the gut are so smart, in fact, that they can control gut behaviour on their own. This means our actual brain does not need to get involved in the process of digestion - the brain in gut takes care of it instead.
And guess how the nerves in the gut speak to each other, and to other cells? By chemical messengers called "neurotransmitters."
Yes - these are the same type of neurotransmitters that work in the brain. In fact, many of the neurotransmitters that have a strong effect on our mood are made in the gut! Case in point? A whopping 90-95% of serotonin is made in your gut, not in your brain!
Many of you may recognize serotonin as the “happy” neurotransmitter - that regulates mood, sleep, and appetite. But other neurotransmitters that are part of the enteric nervous system like dopamine, epinephrine and norepinephrine also play a big role in gut and brain health. They work to regulate and control blood flow, nutrient absorption, gut motility, and the microbiome.
When levels of these neurotransmitters become dysregulated, as in IBD and Parkinson’s Disease, gastrointestinal problems are the result.
But the second brain is responsible for much more than digestion - as it influences our emotions, moods, and mental health, as well.
The immune system of the gut
Because eating and drinking is a huge portal where disease-causing critters can get into your body, it makes total sense that much of our defence system would be located there too, right? Seventy-five percent of our immune system is in our gut!
And you know that immune cells can move throughout the entire body and cause inflammation just about anywhere, right?
Well, if they’re “activated” by something in the gut, they can potentially wreak havoc anywhere in the body. Including the potential to cause inflammation in the brain.
It is believed, and backed by science, that there are trillions of microbes living in our gastrointestinal tracts. The collection of these microbes is commonly called our “gut microbiotia” or “gut microbiome.” Collectively, these microbes play a significant, though mysterious, role in many aspects of our mental health, from neuropsychiatric disorders to psychological resilience.
You can think of these microbes as your friendly neighbourhood gut residents. And yes, you have billions or trillions of these little guys happily living in your gut. But don’t be alarmed - they do amazing things for you! They help you digest certain foods, make certain vitamins, and even help regulate inflammation!
But more and more evidence is showing that changes in your gut microbiota can impact your mood, memory, cognition, and other, more serious, mental health issues.
How do these all work together for brain health?
The honest answer to how these things all work together is that we really don't know just yet. More and more studies are being done to learn more.
But one thing is becoming clear. A healthy gut goes hand-in-hand with a healthy brain! [quote]
So, how do you feed your brain?
Of course, a variety of minimally-processed, nutrient-dense foods is required, because no nutrient works in isolation. Other nutritional tools that can improve the health of your gut microbiome include the addition of probiotics and prebiotics to your diet.
In addition, two things that you many consider eating more of are fibre and omega-3 fats. Fibre (in fruits, vegetables, nuts & seeds) help to feed your awesome gut microbes. And omega-3 fats (in fatty fish, walnuts, algae, and seeds like flax, chia, and hemp) are well-know inflammation-lowering brain boosters.
Of course, if you’d like more information about what and how to feed your brain (or gut), feel free to contact me. I’d be happy to help.
And as always, I’d love to hear what you think. Drop me a line, or comment below with your thoughts.
And be sure to stay tuned to learn more about my upcoming workshop on how to “Eat your way to a happier day” with my friends at ahhYaY Wellness Cafe in Kamloops. Check out the dates and times on my Facebook page and Instagram account @thenutritionalnerd. Hope to see you there!