Dysbiosis: Finding the Right Balance and Benefits

We know that everything in our bodies is connected in one way or another. The gut and the central nervous system (CNS) are one of these connections. The communication between these two is called the gut-brain axis (GBA), and it has been recently discovered that inflammation in the gut can have an impact on our CNS, causing or worsening mental health disorders and symptoms. The inflammation in the gut can be caused by dysbiosis. Dysbiosis is an imbalance of bacteria in the gut, also known as microbiota. What does this communication look like? What kind of disorders can be improved? What can we do to help?

The gut-brain axis pathway. Image created by Megan Clapp and Emily Wilen

The gut releases chemicals that play a vital role in communication with the CNS, like hormones and neurotransmitters, as signals for the brain. When the gut is inflamed, the type of hormones and neurotransmitters changes, and the communication changes. This gut inflammation is often caused by...you guessed it...dysbiosis. Now, this communication begins early in life during pregnancy and birth. There is microbiome transmission through the placenta, amniotic fluid, and in some cases, meconium (first baby poop inside mommy). There has also been a correlation between the amount of bacteria passed to the fetus and the type of birth. As expected, babies born vaginally have a higher concentration of bacteria in their bodies compared to those born by C-section. This, along with breast milk, continues to provide the right kind of bacteria and reduces the likelihood of gastroenteritis (inflammation of the stomach and intestines).

Inflammation of the gut puts stress on the microbiome (microorganisms in the body, not just the gut) and causes it to release other chemicals that "influence brain function, leading to anxiety, depression, and memory loss." Chemical dysfunction in the brain is one of the causes of depressive disorders. Dysbiosis also causes intestinal permeability (leaky gut) that can have effects on the immune system, which is present in diseases like inflammatory bowel disease, asthma, diabetes, and psychiatric disorders like anxiety and autism. Brain-derived neurotrophic factor (BDNF) supports the development of new neurons and pathways in the brain and is also affected by the decrease in microbiota. Studies have found that this can be corrected by recolonization with Bifidobacteria species.

Probiotics contain numerous kinds and numbers of bacteria to help with microbiota regulation. There was a study performed for 30 days where 30 volunteers were either treated with antidepressants or probiotics. Results showed that subjects taking probiotics had decreased cortisol levels (stress hormone) and improvement in physiological symptoms like those being treated with diazepam or citalopram (medication sometimes used for anxiety). Not all subjects had this effect, and it is one of the reasons there are ongoing studies on the benefits noticed in others. Probiotics cannot be a substitute for medication prescribed for mental disorders, but GBA is real and established. It is also clear that improved microbiota plays a vital role in gastrointestinal function and symptom relief.

Another way to help maintain a healthy microbiota is through our food. The "diet" story is long and is influenced by many things, including cultural background and beliefs. What is known is that a wide variety of foods that include fresh vegetables, fruits, lean meats, whole grains, and healthy fats can influence gut microbiota. There should also be good fiber intake, and the consumption of processed foods and added sugars should be limited. Antibiotic use should also be avoided as much as possible, since it can "wipe out" your hard labor in building gut microbiota. Natural probiotic foods include yogurt, kefir, kimchi, sauerkraut, and other fermented foods like pickles. Prebiotics feed the good bacteria in your gut and are present in foods like garlic, onions, bananas, and asparagus.

Find your own style and get the right balance for your gut to keep the right spark in your brain. Make it fun by finding new ways to experiment with food. Food for me, and I know for many others, is one of the most beautiful pleasures in life. It is also a huge debate, thinking that we are "missing out" when we have to "diet." Change the way you think about food and don't follow a "diet." Follow a lifestyle that keeps you healthy, feeling happy, and also a little adventurous when you add a new food that you may find pleasure and benefit in. As Pocahontas would say: "Eat from all the colors of the wind"... or something like that.

References:

Clapp M, Aurora N, Herrera L, Bhatia M, Wilen E, Wakefield S. Gut microbiota's effect on mental health: The gut-brain axis. Clin Pract. 2017 Sep 15;7(4):987. doi: 10.4081/cp.2017.987. PMID: 29071061; PMCID: PMC5641835.

Aziz T, Hussain N, Hameed Z, Lin L. Elucidating the role of diet in maintaining gut health to reduce the risk of obesity, cardiovascular and other age-related inflammatory diseases: recent challenges and future recommendations. Gut Microbes. 2024 Jan-Dec;16(1):2297864. doi: 10.1080/19490976.2023.2297864. Epub 2024 Jan 4. PMID: 38174551; PMCID: PMC10773664.