Gut Health 101
You may have heard someone refer to having a “gut feeling,” or a “punch in the gut,” but what actually is the “gut?” The answer is — our intestines! The role of our intestines is to primarily digest and absorb nutrients we obtain through dietary sources. It allows our bodies to reap the benefits from all the food we eat! Everything we eat passes through our intestines to our colon to be excreted, and each food we eat all leave their blueprint on us before they leave our body. These blueprints compromise the collection of bacteria that lie within our gut - also known as the gut microbiota. Our gut microbiota is the collection of information in our body that helps to increase our immunity, keep us happy, and most of all, keep us alive!
70% of our immune system is compromised within our intestines (Collen, 2015). So those people who have a wide blueprint, or diverse microbiota, of bacteria in their gut often have stronger immune systems than those that do not. That means you’d probably like your collection of bacteria to be strong, well-nourished, and ready to fight off disease, right? Below I will discuss how to strengthen your gut health.
Probiotics vs Prebiotics
The first thing to distinguish is that probiotics are actual living strains of bacteria that add to the diversity of our microbiota. Well, what helps to feed these to become stronger and more diverse? The answer is prebiotics. Think of prebiotics like fertilizer, and probiotics like grass. Grass and fertilizer work as a team to create a beautiful lawn just as prebiotics and probiotics work together to give you beautiful gut health.
Prebiotics are plant fiber such as fruits, vegetables, and whole grains. You can’t have a diverse microbiota without these types of foods feeding them - just like it would be pointless to throw fertilizer on asphalt! Additionally, a diet high in prebiotics (or simply speaking - dietary fiber) has been shown to increase the production of short chain fatty acids (SCFAs) (Kim, et al., 2017). Short chain fatty acids are produced in the gut by bacteria that is fermented from insoluble fiber. They are used as substrates for energy in the body and help in the metabolism of glucose and lipids. SCFAs have also been linked to reducing risk of inflammatory diseases, heart disease, and diabetes (De Fillipis, et al., 2015). By eating more plants, and more importantly a diverse array of plants, you can increase your production of SCFAs, give probiotics “fuel,” and keep your gastrointestinal tract happy and healthy. Additionally, you can obtain probiotics naturally by including fermented foods in your diet such as yogurt, kefir, kombucha, sauerkraut, and kimchi.
Research on Probiotics in Athletic Populations
Research has shown individuals who exercise on a regular basis have a much different microbiota profile than those who do not. In athletic populations, probiotics can actually enhance the absorption of some nutrients, including amino acids from dietary protein. Additionally, it’s important to note that with excessive training loads, immune function can decline to do acute inflammation, disturbed sleep, and/or inadequate recovery. Probiotics have shown to enhance immunity by reducing the severity of upper respiratory tract infections. “Preclinical and early human research has shown potential probiotic benefits relevant to an athletic population that include improved body composition and lean body mass, normalizing age-related declines in testosterone levels, reductions in cortisol levels indicating improved responses to a physical or mental stressor, reduction of exercise-induced lactate, and increased neurotransmitter synthesis, cognition and mood.” (Jäger, et al., 2019)
Research on Probiotics and Mood
Probiotic consumption can improve mood and clinical depression symptoms via a mechanism to inhibit pro-inflammatory actions in the HPA axis (Goh, et al., 2019). Our microbes also have the power to modulate endocrine responses and send neurotransmitters into the CNS. “Neurotransmitters, including serotonin, dopamine, noradrenaline, and GABA, are both indirectly regulated by the presence of certain gut bacteria, and are produced by certain bacteria” (Haas Neill and Forsythe, 2020). This is all the more reason to diversity the types of pre and probiotics we consume. There is emerging evidence in human studies showing probiotics and the blueprint of the microbiota directly can affect our stress responses, mood, and CNS.
Top 5 tips to Improve Gut Health:
1) Eat a wide variety of prebiotics and probiotics
2) Include lean protein in your diet
3) Include sources of healthy fats (specifically Omega-3s) in your diet
4) Aim to get 7-9 hours of sleep a night
5) Exercise regularly
Top 5 Hinderances to Gut Health/Factors that Cause Dysbiosis:
1) Taking antibiotics
2) Chronic stress
3) Hydrogenated oils (trans fat)
4) Processed Meat
5) Added sugar
The takeaway - our gut health is being evolved every day - either strengthened or weakened. Every meal you eat, every night’s sleep you get, stress you take on, and sickness you accrue is affecting your gut health. The next time you reach for a snack or stay up all night, consider your gut health and how you can change your unhealthy habits to benefit not only your microbiota, but also your happiness, immunity, and longevity!
References:
1. Collen, A. (2015). 10% human: How your body's microbes hold the key to health and happiness.
2. Kim, D., Zeng, M. Y., & Núñez, G. (2017). The interplay between host immune cells and gut microbiota in chronic inflammatory diseases. Experimental & molecular medicine, 49(5), e339. https://doi.org/10.1038/emm.2017.24
3. Jäger, R., Mohr, A.E., Carpenter, K.C. et al. International Society of Sports Nutrition Position Stand: Probiotics. J Int Soc Sports Nutr 16, 62 (2019). https://doi.org/10.1186/s12970-019-0329-0
3. De Filippis F, Pellegrini N, Vannini L, et al. High-level adherence to a Mediterranean diet beneficially impacts the gut microbiota and associated metabolome. Gut 2016;65:1812-1821.
4. Goh KK, Liu YW, Kuo PH, Chung YE, Lu ML, Chen CH. Effect of probiotics on depressive symptoms: A meta-analysis of human studies. Psychiatry Res. 2019 Dec;282:112568. doi: 10.1016/j.psychres.2019.112568. Epub 2019 Sep 17. PMID: 31563280.
5. Haas-Neill, S., & Forsythe, P. (2020). A Budding Relationship: Bacterial Extracellular Vesicles in the Microbiota-Gut-Brain Axis. International journal of molecular sciences, 21(23), 8899. https://doi.org/10.3390/ijms21238899
