Gut Instinct: Nurturing the Brain-Gut Connection for Optimal Well-being
As we enter the New Year, many of us may be thinking about setting new health or lifestyle goals. A focus on nutritious eating is commonly considered when setting health goals, and it is not without merit: nutritious eating has benefits for our mental health, in addition to benefiting our physical health.
Maybe you’ve noticed how consuming some foods leave you feeling energized and uplifted, while other foods contribute to low mood? These experiences are not coincidental, and are a manifestation of the complex relationship between your brain and digestive system. In this blog post, we discuss the gut-brain connection and the intricate relationship between the food on your plate, digestive health, and mental well-being.
The Gut-Brain Connection
The ‘brain-gut connection’ is a common phrase that is becoming increasingly popular; it generally refers to the communication system between our brain and digestive system. The gut is sometimes called the 'second brain’ because it essentially has its own network of neurons that work independently from the main brain[1] – but communicates and sends signals to the brain through certain pathways in the body. However, this brain-gut connection is much more than a simple connection, it is a complicated network that also includes various endocrine, metabolic, and immune communication pathways, which all interact with our brain[1,2].
The gut communicates with the brain through unique pathways that are not used by any other bodily system, highlighting the significance of the dynamic interplay between the brain and the gut[2]. Importantly, the communication between the brain and gut is bi-directional, meaning that the brain influences the gut, and, the gut also has a profound impact on the brain[1]. The vagus nerve, the longest and most widely distributed nerve in the body, is responsible for transmitting signals from the gut to the brain and vice versa[3,4].
However, the signals between the gut and the brain can be influenced by various factors, including the gut microbiota. The gut microbiota refers to the community of microorganisms, including bacteria, yeasts, and viruses, that live in the human gut[3]. The vagus nerve can sense the signals generated by the gut microbiota and transfer this information to the central nervous system (the brain and spinal cord), where it is processed and an appropriate response is generated[4].
Impact on Mental Health
Although the brain-gut connection has been evident to scientists since the 19th century[1], research on its relationship with mental health was limited until more recently. Emerging evidence suggests that the brain-gut connection plays a role in mood and psychiatric disorders, meaning gut health may be critical for mental health and well-being[1,3].
For example, a multi-step process occurs when we are stressed[5] which results in the release of cortisol - the primary stress hormone in our bodies. Interestingly, substances produced by our gut microbiota can enter the bloodstream and signal to the brain via the vagus nerve, which in turn, can influence processes in our body such as inducing our stress response (fight or flight response)[2]. In other words, the composition of the gut microbiome can trigger or influence the activity of our stress response system, thereby influencing how we experience stress.
Additionally, inflammation of the gut or alterations in the gut microbiome have been linked to various mood and neuropsychiatric disorders[1]. For example, irritable bowel syndrome has been linked with depression and anxiety disorders[3], and symptoms of depression and anxiety are more frequent among individuals who have inflammatory bowel disease compared to people with healthy gut microbiomes[2,3]. This research demonstrates the impact of the brain-gut connection on overall wellness and emphasizes the importance of maintaining a healthy gut microbiota. So, if we want to help ensure that our gut microbiota has a positive impact on our mental health, what can we do?
How to Cultivate a Healthy Gut Microbiome
Consume a wide variety of plant-based foods
Interestingly, the more diverse your diet, the better your microbiome. Research shows that individuals who consume 30 different plant foods a week supports a more diverse microbiome[6]. In addition, people who consumed more than 30 different plant foods a week had less antibiotic resistance genes, compared to those who consumed less than 10. The reason for the benefit in variety is different components of different plant foods feed different bacteria.Eat mindfully when you can
Mindful eating involves being fully present when you’re eating. Most common practices include getting off of technology when you eat, and thoroughly chewing your food. Through mindful eating, the food is generally chewed more, resulting in better broken-down food, more absorbable components and a higher cognitive awareness of eating. In better breaking down the food, we can better absorb the nutrients, leading to better digestion[7].
Consume fermented foods daily
Fermented foods have anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-diabetic and anti-atherosclerotic properties[8]. Examples of fermented foods include kimchi, yogurt, sauerkraut, and kefir. What makes them so beneficial is that they contain live probiotic cultures. These ‘good’ bacteria continue to add more diversity to the gut microbiome, a benefit mentioned above. If you’re new to fermented foods, start slowly, with 1 TBSP of sauerkraut with your dinner, for example, and work your way up to 1-2 ¼ cup servings per day.
Consume high fiber foods
When you have the beneficial bacteria in your gut, dietary fiber is fermented by these bacteria into something called short-chain fatty acids, which also have anti-inflammatory effects. The dietary fiber is essentially food for the beneficial bacteria in your gut, keeping the microbiome balanced. The rough guidelines is a minimum of 25g/fiber per day for women and 38g/day for men.
As the gut and brain are intricately connected and communicate with one another, taking consistent steps toward mindful nutrition, stress management, and other positive lifestyle choices is a fundamental investment in not only your gut health, but your mental health and wellbeing too.
This blog post was written in collaboration with HEAL Wellness, an organization providing customized, done-for-you workplace wellness programs that improve the health, happiness, and engagement of employees. Specific services they offer include lunch and learns, wellness challenges, and a wellness platform (app), among others. These programs address various dimensions of well-being, including nutrition, movement and mental health. If you’re interested in providing holistic and comprehensive support to your employees, visit their website here!
At WellIntel Talks, we aim to ensure that the community has access to evidence-based, high-quality mental health and wellness information. Our qualified and diverse experts in the field of mental health and wellbeing are available for corporate events, lunch and learn sessions, or training sessions. Our wellness speakers can cover everything from mental wellbeing to harnessing motivation to positive body image to optimizing brain health! To view our wide selection of different talks and topics, you can visit our website here!
Written By:
Mandy King, Holistic Nutritionist, Owner of HEAL Wellness
WellIntel Talks Team
References:
[1] Borre, Y. E., Moloney, R. D., Clarke, G., Dinan, T. G., & Cryan, J. F. (2014). The impact of microbiota on brain and behavior: Mechanisms & therapeutic potential. Advances in Experimental Medicine and Biology, 817, 373–403. https://doi.org/10.1007/978-1-4939-0897-4_17
[2] Appleton, J. (2018). The gut-brain axis: Influence of microbiota on mood and mental health. Integrative Medicine (Encinitas, Calif.), 17(4), 28–32.
[3] Lee, Y., & Kim, Y.-K. (2021). Understanding the connection between the gut–brain axis and stress/anxiety disorders. Current Psychiatry Reports, 23(5), 1–7. https://doi.org/10.1007/s11920-021-01235-x
[4] Bonaz, B., Bazin, T., & Pellissier, S. (2018). The vagus nerve at the interface of the microbiota-gut-brain axis. Frontiers in Neuroscience, 12, 49. https://doi.org/10.3389/fnins.2018.00049
[5] Misiak, B., Łoniewski, I., Marlicz, W., Frydecka, D., Szulc, A., Rudzki, L., & Samochowiec, J. (2020). The HPA axis dysregulation in severe mental illness: Can we shift the blame to gut microbiota? Progress in Neuro-Psychopharmacology and Biological Psychiatry, 102, 109951. https://doi.org/10.1016/j.pnpbp.2020.109951
[6] McDonald, D., Hyde, E., Debelius, J. W., Morton, J. T., Gonzalez, A., Ackermann, G., Aksenov, A. A., Behsaz, B., Brennan, C., Chen, Y., DeRight Goldasich, L., Dorrestein, P. C., Dunn, R. R., Fahimipour, A. K., Gaffney, J., Gilbert, J. A., Gogul, G., Green, J. L., Hugenholtz, P., … Knight, R. (2018). American Gut: an Open Platform for Citizen Science Microbiome Research. MSystems, 3(3). https://doi.org/10.1128/MSYSTEMS.00031-18
[7] Cherpak C. E. (2019). Mindful Eating: A Review Of How The Stress-Digestion-Mindfulness Triad May Modulate And Improve Gastrointestinal And Digestive Function. Integrative medicine (Encinitas, Calif.), 18(4), 48–53.
[8] Şanlier, N., Gökcen, B. B., & Sezgin, A. C. (2019). Health benefits of fermented foods. Critical reviews in food science and nutrition, 59(3), 506–527. https://doi.org/10.1080/10408398.2017.1383355