Have you ever been nervous or excited and felt a sudden urge to run to the toilet for a bowel motion? Maybe you have gone from being ravenously hungry to completely nauseous when something upsetting happens. This is the gut and brain working together. Think of it as an extremely high functioning phone line. And this communication network is called the gut-brain axis. The two are connected both physically and biochemically in a few ways. Let’s take a look!
The connection of the Gut-Brain Axis
Up until recently, we have been giving credit or placing blame on the brain for our moods and emotions. We are seriously underestimating the health of our gut and its role. Just so you can completely understand the complexity of the gut-brain axis, let’s just have a review of the autonomic nervous system (ANS). It runs thousands of automatic functions which are steadily chugging along in the background. It controls our fight or flight reactions vital to our survival, through our sympathetic nervous system (SNS). It also influences our repair systems throughout the body with the parasympathetic nervous system (PNS) through the process of rest and digest. These signals should be even – so you feel balanced. When one dominates, you can feel stuck. Most often it’s usually the SNS, being in fight or flight mode. Feeding into this ANS is the enteric nervous system (ENS) which is a massive mesh-like network of neurons that are embedded in the wall of your gastrointestinal tract. The ENS receives signals from both your SNS and PNS. The ENS contains the vagus nerve. It is one of the most significant nerves connecting your gut and brain. Science has found gut bacteria have neurotransmitter receptors allowing them to communicate directly with the brain via neural pathways such as the vagus nerve (Carabotti, Scirocco, & Severi, 2015). It sends signals in both directions. It is quite literally a direct line of communication between your gut microbiome and your brain. The ENS is responsible for generating and moving neurotransmitters. Neurotransmitters are what control your emotions and feelings. About 95 percent of serotonin being created by nerves and microbes in the gut (Yano, et al., 2015). Serotonin contributes to feelings of happiness and helps control your body clock. Your gut microbes also produce a neurotransmitter called gamma-aminobutyric acid (GABA), which helps regulate feelings of fear and anxiety. (Foster & Neufeld, 2013). The gut-brain axis is also connected through the immune system. If your immune system is switched on for too long, it can lead to inflammation which is associated with some brain health disorders (Lucas, Rothwell, & Gibson, 2006).
How Gut microbiota imbalance may affect Mood
You understand the two are connected in a few ways. But how does the gut microbiota have such an impact? The gut contains billions of organisms called microbiota. In fact, 90-95 percent of the cells in the gut are microorganisms. A healthy balance of these microorganisms is essential for both mental and physical health. Unfortunately, aspects of modern life such as constant stress, diets high in processed food, antibiotics, and pesticides have decreased both the amount and richness of healthy gut microbiota, while increasing the level of unhealthy microorganisms. There are four primary ways your gut microbiome can contribute to mood issues such as anxiety and depression (VIOME, 2018).
1. By influencing your stress responses
Your gut microbiome modulates your stress response through the production of serotonin and helps to lower cortisol – the stress hormone.
2. Through a leaky gut
Dysbiosis (imbalance in microbiome) and inflammation of the gut have been linked to causing several mental illnesses including anxiety and depression, which are prevalent in society today (Clapp, et al., 2017). It has been found that when there is a change in the composition of the gut microbiome, it can cause problems such as a leaky gut. This is when the lining of the gut allows proteins, viruses, bacteria and other particles such as undigested food to leak out of the gastrointestinal tract and into the bloodstream. This causes the ENS and the brain, via the CNS to miscommunicate. It contributes to poor cognitive functions and inappropriate emotional responses.
3. By causing chronic inflammation
Chronic inflammation is promoted by harmful microbes. This occurs when the bad bacteria outcompete the beneficial bacteria in the gut. When this inflammation happens, it can activate the vagus nerve and lead to neuropsychological symptoms.
4. Through producing harmful peptides.
Gut peptides could be telling your brain you are stressed. Harmful bacteria can create peptides know to send stress signals to your brain. Ensuring you have a healthy composition of gut microbiome to reduce the harmful peptide concentration is critical in reducing stress signals.
So how can we use this information to improve our mood?
The most important takeaway from this information is – the gut microbiome influences our brain at least as much as the brain affects the gut. Your gut microbiome is unique, but it’s also dynamic and continually changing. Therefore, it is essential to boost beneficial microbes while decreasing the harmful ones. Your diet and lifestyle choices are the most potent tools to affect change in the gut microbiome. Making lifestyle choices to effectively decrease your flight or fight response, such as meditation, yoga and mindfulness may also go a long way in positively improving your gut health and mood. Prebiotics, which are fibres fermented by your gut bacteria, definitely affect gut health but may affect brain health. A study has found that taking a prebiotic for three weeks significantly reduced the amount of stress hormone in your body called cortisol (Schmidt, et al., 2014). Gut Performance™ is an effective prebiotic. Taking Gut Performance™ as directed in conjunction with a gut health enhancing diet and lifestyle changes, you may be able to decrease inflammation and positively influence your gut and brain health. Let us know via our Gut Performance™ Instagram page if you have tried Gut Performance™ and how it has improved your gut health and mood symptoms. We love to hear about your success in achieving greater wellbeing.
Carabotti, M., Scirocco, A., & Severi, C. (2015). The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Annals of Gastroenterology, 28(2), 203-209.
Clapp, M., Aurora, N., Herrera, L., Bhatia, M., Wilen, E., & Wakefield, S. (2017). Gut microbiota’s effect on mental health: The gut-brain axis. Clinics and Practice, 7(4), 987.
Foster, J. A., & Neufeld, K.-A. M. (2013). Gut-brain axis: how the microbiome influences anxiety and depression. Trends in Neurosciences, 36(5), 305-312. Retrieved 4 2, 2019, from https://sciencedirect.com/science/article/pii/s0166223613000088
Lucas, S., Rothwell, N., & Gibson, R. (2006). The role of inflammation in CNS injury and disease. British Journal of Pharmacology, 147(Suppl), S232-S240.
Schmidt, K., Cown, P., Harmer, C., Tzortzis, G., Errington, S., & Burnet, P. (2014). Prebiotic intake reduces the waking cortisol response and alters emotional bias in healthy volunteers. Psychopharmacology, 232(10), 1793-1801. doi:10.1007/s00213-014-3810-0 VIOME. (2018, June). https://viome.com/blot/anxiety-depression-your-gut-microbiome-blame. Retrieved March 2019, from Viome: https://viome.com
Yano, J., Yu, K., Donaldson, G., Shastri, G., Ann, P., Ma, L., & Hsiao, E. (2015). Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell, 161(1), 264-276.