Updated: Jun 17
The Gut-Brain Connection - How your gut and brain talk to each other.
If you’ve ever had the so-called “Gut feeling” or “Butterflies in your stomach”, you are likely getting signals from an unexpected source: Your Second Brain. Yes, your brain and gut are actually connected and scientists call this bi-directional communication the gut-brain axis (GBA).
Recent studies show that your brain affects your gut health and your gut may even affect your brain health.
How are the gut and brain connected?
Your gut is home to trillions of bacteria and other microbes and they are physically connected to the brain via the vagus nerve and this is also called the enteric nervous system (ENS).
Your gut and brain are also connected through chemicals called neurotransmitters. Neurotransmitters control your feelings and emotions. Your gut microbiome communicates by creating and consuming the majority of your body’s neurotransmitters. 90% of your “happy” neurotransmitter-serotonin is made by your gut microbiome. Your gut microbes also produce a neurotransmitter called gamma-aminobutyric acid (GABA), which helps control feelings of fear and anxiety. Studies in laboratory mice have shown that certain probiotics can increase the production of GABA and reduce anxiety and depression-like behavior.
Your gut microbes also make other chemicals that affect the brain called short-chain fatty acids (SCFAs) such as butyrate, propionate, and acetate. They make SCFA by digesting fiber. SCFAs affect brain function in a number of ways, such as reducing appetite, promoting healthy intestinal and blood brain barrier.
Therefore, a change in the composition of your gut microbes has been shown to significantly affect:
Your pain tolerance
Your cognitive performance
Your mental health
It’s found that when the gut ecosystem is out of balance it can cause brain fog, depression, and even dementia. In fact, new areas of neuroscience are looking from the bottom-up and focusing on how the gut impacts the brain. All of these findings and more have earned your gut microbiome the nickname – the second brain. Your second brain has significant effects on every function in your body. The composition of the microbiome and its activities are involved in most, if not all, of the biological processes that constitute human health and disease. So, when it comes to improving brain health, a great way to start is by paying attention to the health of your gut.
Healthy gut, Healthy brain
What you eat is one of the most important factors influencing your health. The foods you eat are broken down and transformed by your gut microbiome to nourish the rest of your body.
You are what you eat – and if you aren’t eating the right foods for a healthy brain (and second brain) then you’re going to feel it. We’ve all experienced times where we felt as though we couldn’t access the full capacity of our brain – this can often be due to the gut-brain connection.
Depending on what microbes are inhabiting your gut right now, they can take the food you eat and metabolize it into beneficial nutrients or harmful metabolites.
For example, neurotransmitter production in the brain is dependent on specific proteins, vitamins, and minerals. Your brain needs a balanced intake of complex carbohydrates, proteins, and vitamins to keep you at your best. Folic acid, for instance, is critical for brain function and cognition. Your microbes are responsible for metabolizing your food to keep a steady supply of folic acid flowing to the brain. If microbes aren’t fed properly, their ability to create specific vitamins, like folate, decreases and impacts neurotransmitter synthesis. This leaves your brain struggling to communicate and the “brain fog” sets in.
Probiotics & the Gut-Brain Axis
Gut bacteria affect brain health, so changing your gut bacteria may improve your brain health. The birth of probiotics was a direct result of the science behind the gut microbiome. Probiotics are live bacteria that impart health benefits if eaten. However, not all probiotics are the same. Probiotics that affect the brain are often referred to as “psychobiotics”. There are specific strains of probiotics that have been shown to improve symptoms of stress, anxiety, and depression.
More research is needed to really understand which microbes, and which combination of microbes, will be most beneficial for your gut-brain connection.
Until then, it’s all about feeding the right microbes the right foods, so they can thrive in the complex ecosystem of your gut. When you’re eating the right nutrients for your microbiome, the health benefits are passed on to your brain.
Food that helps in Gut-Brain Axis
1. Omega 3 fats - Increases good bacteria in the gut and also reduces inflammation in the body, helps to reduce the risk of brain disorders.
2. Fermented foods - Kimchi, tempeh, sauerkraut, kefir, and kombucha all contain healthy microbes that may alter brain activity.