Have you had butterflies or an urge to use the bathroom when you’re nervous or stressed?
These sensations are evidence of the gut-brain connection.
Here’s a quick story to illustrate how the gut and brain are connected.
Growing up I raced track and field. I remember my dad taking me to the track for races. He patiently stood with me while I warmed up.
The issue is, before races I am a nervous wreck. I’d visit the bathroom multiple times in the last 15 minutes before any race... expelling my insides.
Even directly after, I’d have butterflies and sensations that I had to urinate. The same sensations replayed before long-car rides. This made for a stressful time getting to summer camp.
In hindsight, maybe my gut-brain connection was too strong.
What is the gut-brain connection?
Research shows that your brain can communicate directly with your gut. Your gut can also talk to your brain.
This communication network is referred to as the gut-brain connection. Some go so far as to call the gut our second brain (1).
This is why anger, sadness, happiness, depression and anxiety can all produce symptoms in your gut (2).
So can the thought of eating. When you’re hungry, your gut begins to release stomach juices to prepare for incoming food.
As I mentioned above, this connection goes both ways.
When you have gut issues, it can cause anxiety, depression or stress (3).
How does this happen?
The gut and brain are connected physically through something called the vagus nerve.
What is the vagus nerve?
The vagus nerve is a spindly collection of nerves that runs from the back of your brain down to your organs and gut (4).
The vagus nerve is responsible for automatic or unconscious bodily processes like controlling your heart rate and digesting food.
It helps connect the 500 million neurons in your gut to the 100 billion neurons in your brain (5).
In case you’re wondering, neurons are cells in your gut and brain that tell your body what to do.
Studies show that people with Crohn's Disease or Irritable Bowel Syndrome suffer from a dysfunction of their vagus nerve (6).
Also, stress is shown to impair vagus nerve function to cause gut issues in animals.
The vagus nerve is the centrepiece to our gut-brain connection.
How gut bacteria affect your brain
Over 400 species, 100 trillion microbes and three pounds of bacteria make up your gut.
Science people call this system your microbiome, which is crucial to the gut brain-connection.
Your gut microbes help you digest food, regulate hormones, excrete toxins and produce vitamins that directly affect brain function (7).
Hunger is one way your gut affects your brain. Your gut does this by making short-chain fatty acids from fiber in your diet. These fatty acids reduce appetite.
Some studies show that consuming these fatty acids can reduce your desire for food (8).
That is one reason why people tell you to eat more fiber. That.. and fiber keeps your ‘regular’.
How your gut controls your mood
Did you know that 95% of your body’s serotonin resides in your gut? That’s because your gut is responsible for producing neurotransmitters (9).
Serotonin regulates mood, appetite, alertness and energy and plays a major role in depression.
GABA is another neurotransmitter crucial to healthy moods. Our gut bacteria need GABA to thrive.
At this point you may be asking: what is GABA?
GABA calms us down. It helps regulate anxiety and depression. And a lack of GABA could lead to depression (10).
It’s incredibly important to your mental health.
What I find interesting is that GABA is being used to restore gut bacteria to treat depression (11).
Ok, so now we know that a healthy gut means a happy life. How do we know if our gut isn’t healthy?
Inflammation, gut health, depression and dementia
A strong gut-brain connection is crucial for a resilient immune system.
Your gut bacteria is responsible for controlling inflammation.
There is a mucosal lining in your gut. This lining is like a bouncer or doorman in a nightclub.
Your gut lining controls which food particles go into your bloodstream and which get denied.... (and go home early... sounds like me in university).
Bad food, stress and pollution all cause wear and tear on your gut lining, making it porous.
This is referred to as Leaky Gut Syndrome.
It’s like the bouncer left and everyone can get into the club. Chaos. (12).
The problem is that your immune system gets activated when particles start leaking through your gut lining.
If you have a leaky gut, then your immune system is constantly activated, leading to inflammation.
This inflammation creates harmful toxins in your gut bacteria, which have free access to your bloodstream if your gut is leaky.
Inflammation causes many brain disorders like Alzheimer’s, depression and schizophrenia (13).
Of note for you and me, inflammation is implicated in just about every other chronic disease, including heart disease, diabetes and autoimmune conditions.
Anxiety and the gut-brain connection
Given the gut-brain connection, it makes sense that you get butterflies before a presentation. Or in my case, have to go to the bathroom before races.
Stress directly affects movements and contractions in your gut and GI (gastrointestinal) tract.
Your gut works with your brain psychology to influence these movements.
Interestingly, people with GI conditions like crohn’s or colitis are more sensitive to pain. This is because their brains are hyper-aware of all signals coming from their gut.
In other words, stress can make your pain feel worse.
The good news is that you can treat GI conditions and improve your gut health by using techniques for anxiety and depression.
The gut-brain connection can help us rebuild our gut health. It starts with managing your stress.
Can probiotics help your gut-brain connection?
We know that gut bacteria affects brain health. How do probiotics fit into the equation and what are psychobiotics? Read below, my friend.
Probiotic and prebiotic foods have a protective effect on your gut.
Prebiotics, the less known cousin to probiotics, are soluble fibers that feed good bacteria in your gut.
Prebiotics reduce the nasty stress hormone: cortisol.
Probiotics are good bacteria already living in your large intestine. They feed on prebiotics to flourish and grow.
Prebiotic foods include:
- Artichoke hearts
- Chicory root
Probiotic foods that can complement your existing gut bacteria include:
- Pickled foods
Read your labels carefully. You want to avoid buying anything with added sugar or preservatives.
Yogurt in particular is full of sugar. Opt for full fat yogurt that is plain or unsweetened. You can add your own sweetener like maple syrup, cinnamon or berries.
Psychobiotics: the new probiotic
There is a new class of probiotics referred to as psychobiotics which are specifically used to optimize the gut-brain connection.
Early research suggests that psychobiotics can help to treat depression, chronic fatigue syndrome and irritable bowel syndrome (14).
Other studies use different psychobiotics to treat stress, anxiety and depression (15).
In other words, food is medicine.
Food can directly improve your mood (16).
How cool is that?
The specific strain of psychobiotic used is Bifidobacterium longum NCC3001 taken for 6 weeks.
Foods to strengthen your gut-brain connection
Now you probably skipped the whole article to get this food list.
Before you add foods, make sure you should avoid inflammatory foods or else your efforts will be useless.
You should also avoid processed foods as they kill your gut bacteria.
The Mediterranean Diet is a great starting point to optimize your gut-brain connection. It’s shown to be protective against depression (17).
The Mediterranean Diet focuses on whole grains, seafood and poultry, beans, legumes, fruit and vegetables (leafy greens, cruciferous vegetables) along with nuts and olive oil for cooking.
If we dig a little deeper, we can find more specific foods for your gut-brain axis.
Omega-3s are found in oily fish and algae. They are also highly concentrated in your brain. Omega-3s help reduce the dangerous inflammation that is responsible for many chronic diseases.
Read my report on Omega-3s here.
As I mentioned above, probiotic rich foods nourish your gut with good bacteria so it can thrive.
A healthy gut-brain connection protects your immune system and keeps you healthy.
Kefir, sauerkraut, kimchi, yogurt and kombucha are all great natural sources of probiotics.
Prebiotics are a soluble fiber that your gut bacteria feeds on. Prebiotics reduce cortisol and help your gut function properly (19).
Natural sources of prebiotics include: asparagus, artichoke hearts, leeks, onions and garlic.
Shiitake mushrooms are naturally high in vitamin B-6. B-6 is crucial to the production of serotonin in your gut (20).
90% of the serotonin is made in your gut. It then travels up your vagus nerve to your brain.
Polyphenols are plant compounds that improve your brain health, memory and healthy gut bacteria (21). They’re important to your nervous system in the gut-brain connection.
Polyphenols are found in green tea, coffee, cocoa and olive oil.
Glycine also helps your digestion by decreasing inflammation and healing damaged tissues in your gut (23).
One cup of Bluebird Provisions bone broth has the 3 g of glycine needed for the gut-brain connection health benefits.
Sesame seeds are rich in tyrosine, an amino acid that increases dopamine in your brain (24). Dopamine helps you feel motivated, and is important to the gut-brain connection.
- Your gut and your brain are physically and chemically connected through your vagus nerve.
- Many of the neurotransmitters in your brain are made first in your gut.
- Healthy gut bacteria directly affects your brain health and function.
- You can improve your brain health, reduce stress and anxiety by changing your gut bacteria.
- There are many foods you can eat to boost your gut-brain connection, these include: omega-3s, probiotics, bone broth, polyphenols, mushrooms, prebiotics and sesame seeds.
Do you get butterflies or feel sick when you’re stressed? Leave a comment and let me know.
Image credit: wildpixel getty images, Science Pictures Online, Tero Getty Images, Tema_kud Getty Images.