No, not the part of your body that hangs over your belt. We're talking about your gastrointestinal system effecting your overall health.
Have you ever had butterflies in your stomach? This is the perfect example of the gut-brain axis, or the connection that exists between the gut and the brain.
There is a two-way communication between your gastrointestinal tract and the nervous system. This two way system means that intestinal distress can be the cause or the product of anxiety, depression or stress.
A Johns Hopkins expert referred to the gut as a second brain hidden within the walls of the digestive system. The gastrointestinal tract is lined with over 100 million nerve cells, and scientists have given it the name “the enteric nervous system”. These nerves, neurons and neurotransmitters found in the gut and brain communicate back and forth. An example of the brain and emotions affecting the gut is irritable bowel syndrome, characterized by hyperactivity of the nerves in the enteric nervous system that can be triggered by emotional shifts.
The gut-brain axis draws interest from the field of neurology, gastroenterology, psychology and nutrition. So far most of the research about this connection is based on animal studies, but human research is underway to help us understand more about the fascinating brain-gut connection.
The Gut Microbiota
Inside your gut there are about 100 trillion living bacteria that influence your health. Of these 100 trillion, there are over 1,000 different species of bacteria, both good and bad, that collectively are known as your gut microbiota. There are many different factors that influence the balance of these bacteria in your body.
Some major influencing factors are:
- Medications (especially antibiotics, which can kill both the good and bad bacteria in the gut)
What does the gut microbiota do?
The gut microbiota has a protective role in addition to other metabolism functions. The gut microbiota protects against intestinal infections such as H. Pylori and C. Diff that can cause infectious diarrhea and even ulcers. The gut microbiota also contributes to immune function. Recent research suggests that certain bacteria strains in the gut can even help protect against various cancers and heart disease. The gut’s more obvious role is to help to metabolize nutrients found in food, as well as some medications. The gut microbiota even synthesizes vitamin K.
The good bacteria of the gut microbiota keeps the pathogenic bacteria in check. When there is an imbalance and the bad bacteria outnumber the good, this is called dysbiosis. Dysbiosis of gut bacteria can negatively affect your health in many different ways and contribute to many chronic diseases including:
- Crohn’s disease
- Ulcerative colitis
The gut microbiota is its own ecosystem that plays an important role in human health. By maintaining the health of your gut, you can influence your health beyond the digestive system.
Probiotics and Prebiotics
Probiotics are defined as living microorganisms that are intended to have benefits on a person's health. These are living bacteria cultures of the good bacteria already found in your gut.
You might recognize the term probiotics from the recent trend of using probiotic supplements. Probiotics are naturally found in fermented foods like aged cheese, cultured non-dairy yogurts, kefir, kimchi, kombucha, miso, sauerkraut, tempeh and yogurt. Read food labels and look for a list of active cultures. Not all yogurts for example contains active culture, but two common ones to look for on a label are bifidobacteria and lactobacilli.
Probiotic supplements are generally recognized as safe for healthy adults, but it’s recommended to consult with your primary care provider or a Registered Dietitian if you are using probiotics for gastrointestinal issues or a weakened immune system. Some of the possible benefits of probiotic supplementation include:
- Enhanced calcium absorption
- Preventing and treating digestive disorders including:
- Gastrointestinal infections
- Irritable bowel diseases
- Irritable bowel syndrome
- Preventing and treating allergic disorders
Prebiotics promote the growth of of probiotics, also known as those good bacteria in your gut. They are non-digestible food components that are naturally found in certain foods like asparagus, bananas, garlic, lentils, nuts, onion, soybeans and whole-wheat products. These prebiotics are gut health promoters, that work with probiotics to maintain a healthy gut.
What you can do to promote gut health
Of the many factors that affect gut health, you can control most of them. Age and genetics are out of your control, but what you choose to do with the remaining factors can change your gut health for the better.
- Drink lots of water
- Eat a range of fruits and vegetables for prebiotics and fiber
- Eat whole-grains for prebiotics and fiber
- Eat fermented foods and/or dairy that contain probiotics
- Avoid things that alter the gut microflora in negative ways if you can- such as alcohol, artificial sweeteners and certain medications
- Take a probiotic supplement if you and/or health care provider deem it a beneficial part of your health routine
Probiotics: In Depth. National Center for Complementary and Integrative Health. 2016. Available at: https://nccih.nih.gov/health/probiotics/introduction.htm. Accessed January 9, 2018.
Publishing H. Can gut bacteria improve your health?. Harvard Health Publishing. 2016. Available at: https://www.health.harvard.edu/staying-healthy/can-gut-bacteria-improve-your-health. Accessed January 8, 2018.
Publishing H. Health benefits of taking probiotics. Harvard Health Publishing. 2015. Available at: https://www.health.harvard.edu/vitamins-and-supplements/health-benefits-of-taking-probiotics. Accessed January 8, 2018.
The Brain-Gut Connection. Hopkinsmedicineorg. 2017. Available at: https://www.hopkinsmedicine.org/health/healthy_aging/healthy_body/the-brain-gut-connection. Accessed January 8, 2018.
Wolfram T. Prebiotics and Probiotics: Creating a Healthier You. wwweatrightorg. 2015. Available at: http://www.eatright.org/resource/food/vitamins-and-supplements/nutrient-rich-foods/prebiotics-and-probiotics-the-dynamic-duo. Accessed January 15, 2018.
Zhang Y, Li S, Gan R, Zhou T, Xu D, Li H. Impacts of Gut Bacteria on Human Health and Diseases. International Journal of Molecular Sciences. 2015;16(4):7493-7519. doi:10.3390/ijms16047493.