As you are reading this blog post, your gastrointestinal system, commonly referred to as your gut, is at work digesting the meal you last ate. If you had some eggs and oatmeal for breakfast, right now your gut is busy breaking it down into smaller, more absorbable constituents needed for energy.
Digestive system definition
Perhaps the scene above is what you think of when you hear the phrase “gut health”. A healthy gut will break down food into smaller pieces that can be used to produce energy molecules and other cellular material. Digestive waste is then excreted out of the gut 1. However, digestion is not the only thing your gut does, and don’t think for a moment that it does it all by itself.
Your gut has an especially important partner. An estimate of 100 trillion bacterial cells lives in your intestines in what is collectively termed the microbiota 2. More bacteria live in your gut than there are cells in your body. Let that sink in (to your gut) for a moment… The microbiota can be thought of as a complex ecosystem. Much like a rainforest, hundreds of different species of bacteria come together to create a balanced environment in your gut. While specific species of bacteria support your gut health, we are learning that the overall balance of the varying species is just as important.
When the microbiota is balanced, it is keeping pathogenic strains of bacteria at bay that would otherwise cause harm to your gut. A healthy microbiota also produces molecules that the cells of your colon use for fuel. The microbiota is not being left out of a meal either. Undigested fibers and starches in your diet get gobbled up by the bacteria and used for energy.
Other functions of gut and microbiota: immune
Other than digest food, absorb nutrients, and eliminate waste, what else does your gut do? To start, your gut is home to nearly 70% of your immune system 3. Your gut is constantly encountering the outside world. Having large amounts of immune tissue in your gut makes sure that toxins and pathogens are taken care of before having the chance to enter your body. The microbiota also supports your immune health by creating chemicals that regulate your immune system, modulate inflammation, and reduce cancer growth 4.
Other functions of gut and microbiota: neurological
Your gut is intimately connected to your brain. Running from your brain stem to the gut is a large nerve called the vagus nerve. The vagus nerve can send signals from the brain to the gut and vice versa. This nerve can respond to various gut hormones, neurotransmitters, and bacterial by-products in the gut. Evidence shows that bacteria in your gut may even alter your emotional and behavioral responses by stimulating the vagus nerve 5.
A dedicated network of neurons webs your gut called the enteric nervous system (ENS). It has been called the “second brain” because its structure is reminiscent of the brain. The ENS can operate independently from the brain. Information can be sent to the brain about what is happening in the gut. It is thought that the microbiota may be using the ENS as a middleman that picks up messages from the microbiota and sends it to the brain 5. With the help of the microbiota, 90% of serotonin is produced in the gut 5. Serotonin is needed for gut motility and influences your mood. Emerging research suggests that conditions such as autism, epilepsy, and schizophrenia may result from imbalances in the microbiota.
Gut health is more than just what is going on in your belly. It is connected to your immune health, neurological health, and overall health. How can you support not only your gut health but overall health and wellbeing? Perhaps the most important place to start is with what your gut encounters every day – food!
Foods for Gut Health
Eat Mostly Whole Foods
- With any healing protocol, the first step is to eliminate triggers of imbalance. Foods that are heavily processed can change the nature of your microbiota for the worse. Eating mostly whole foods provides your gut and the microbiota with the nutrients they need for health.
Foods Rich in Fiber
- Fiber helps promote motility of your gut and is the fuel source your microbiota needs for energy.
- nuts and seeds
- walnuts, pumpkin seeds, pecans, pistachios, almonds, etc.
- non-starchy types like cauliflower, broccoli, dark leafy greens, asparagus, mushrooms, yellow squash, zucchini, peppers, etc.
- strawberries, blueberries, raspberries, black berries, apples, pears, etc.
- nuts and seeds
- Fermented foods contain probiotics, beneficial strains of bacteria that live in the gut.
- pasture-raised, grass-fed yogurt
- sauerkraut, kimchi, or other fermented veggies
- Bone broth is rich in amino acids needed for repairing damaged cells in your gut.
- Demulcent is a term used to describe foods that are soothing to your gut. They help support your mucosal membrane, an especially important protective layer in the lining of your gut.
- chia seed
- flax meal
Keegan Abernathy MS, CNS, LDN, Functional and Integrative Nutritionist received his Master of Science in Nutrition and Integrative Health from Maryland University of Integrative Health (MUIH) and is a Certified Nutrition Specialist (CNS) and Licensed Dietitian Nutritionist (LDN). He has witnessed how nutrition has the ability to heal, empower, and enrich lives. Keegan sees eating not only as a way to optimize health but also as a practice for connecting to our food and body in compassionate ways. He believes that nutrition is an investigation into what we are eating and how we are eating. Gaining insight into these two components of eating allows for transformation, connection, and a joyous sense of well-being. After contracting clostridium difficile (commonly known as C. diff) in 2013, Keegan experienced eating as a fearful experience due to his compromised digestion. Through the power of nutrition, mindful eating, and mindfulness practice, he found a deeper connection to his body and cultivated a positive relationship with food. It is now his mission to guide others to their true nature of health and well-being. Connect with him: https://www.truenaturewellness.net/
- Marieb, E. N. (2015). Essentials of human anatomy & physiology. Glenview, IL: Pearson Education, Inc.
- Guinane, C. M., & Cotter, P. D. (2013). Role of the gut microbiota in health and chronic gastrointestinal disease: understanding a hidden metabolic organ. Therapeutic advances in gastroenterology, 6(4), 295-308.
- Vighi, G., Marcucci, F., Sensi, L., Di Cara, G., & Frati, F. (2008). Allergy and the gastrointestinal system. Clinical & Experimental Immunology, 153, 3-6.
- Cani, P. D. (2018). Human gut microbiome: hopes, threats and promises. Gut, 67(9), 1716-1725.
- Cryan, J. F., O’Riordan, K. J., Cowan, C. S., Sandhu, K. V., Bastiaanssen, T. F., Boehme, M., … & Dinan, T. G. (2019). The microbiota-gut-brain axis. Physiological reviews.