Our gut is considered our “second brain” for very good reason—after all, the phrase “trust your gut” had to come from somewhere, right?
Often referred to as the enteric nervous system, our “second brains” are comprised of neurons embedded in our gut, extending from our esophagus to our anus. There are roughly 100 million neurons found within our gut—more than both our spinal cord and the peripheral nervous system. Further, the neurons in the gut are thought to generate as much dopamine as those in our brains, and they’re responsible for producing about 90 percent of our serotonin (our feel good molecules).
Certain foods—like sugar and alcohol—can throw off the collection of microorganisms that live in our gut, impacting how we think, feel and perform every day. Let’s break down the connection:
Diet and the Brain
For the last 10 years, scientists have been examining the interactions between the gut microbiome, endocrine, immune and nervous systems and the brain. So far, the results are fascinating. Even though there are still many gaps in knowledge and research, it’s clear that diet, gut health and brain health are all connected. The key finding? The standard American diet—as well as diets that are high in refined sugars and simple carbohydrates—can be detrimental to our GI tract as well as our brains. In addition to impacting our body’s insulin response, sugar and refined carbohydrates are also pro-inflammatory and can cause oxidative stress. In the brain, inflammation can result in the expression of anxiety-inducing chemicals, resulting in depressive symptoms like lethargy, sleep interruption and even learning impediments.
Moreover, sugar and refined carbohydrates feed bad bacteria and yeast in our gut which can lead to a whole host of symptoms ranging from allergies and joint pain to major, work-sabotaging brain fog.
But wait, there’s more! Studies are now suggesting that diets high in refined sugar reduce the production of a brain chemical called brain-derived neurotrophic factor (BDNF). When we don’t have enough BDNF, our brains struggle to form new memories and commit to new information. Some research is even linking low levels of BDNF with Alzheimer’s and dementia.
Stress and the Gut-Brain Connection
At this point, we all know that stress can negatively impact our health—but what about our brains’ performance? Scientists are now discovering that there is a real link between physical and emotional stress and our gut microbiota.
In fact, there is even evidence that suggests our gut microbiome responds directly to stress-related signals: Chronic, unmanaged stress can impact your microbiome and impair your gut’s ability to produce much-needed neurotransmitters. The results? Detrimental impacts on both mood and memory.
Gut Bacteria and the Brain
So much happens in the gut that impacts the rest of our biological functions. An unhealthy gut can lead to mood swings, bad skin, foggy brain and autoimmunity. Modern studies are suggesting that mental illnesses, such as schizophrenia, are connected to gut inflammation. There’s even an emerging body of research called psychobiotics that essentially studies the gut/brain connection and the impact of good and bad bacteria on psychiatric and neurological illnesses.
Additionally, scientists and doctors have highlighted a link between certain disorders such as depression and gut health for years. Several studies have examined the gut brain link through the effects of both probiotics and antidepressants on irritable bowel syndrome (IBS). Researchers found that patients suffering from depression were twice as likely to see improvements from probiotic use than those in the control group. In summary, with improved gut health came improved mental wellbeing.
Thanks to the growing field of nutritional psychiatry as well as increased awareness of the gut microbiome and how it affects us systemically, we are increasingly aware of how what we eat impacts not only how we feel in the moment, but how we behave over time. No doubt, the effects of gut microbiota and its link to mental health will be a major area of research over the next decade and beyond.
Nationally recognized wellness expert Amina AlTai is a Nutrition and Corporate Wellness Consultant and founder of Brooklyn-based Busy Happy Healthy. With training in nutrition, fitness and meditation—and having triumphed over burnout to reclaim her own health—Amina specializes in developing meaningful lifestyle practices that enhance the whole person, not just pieces of our lives. Along with individual clients, progressive companies such as Bliss, Deloitte and HUGE have partnered with Amina for wellness coaching that breaks the mold. In addition to penning pieces for digital destinations like MindBodyGreen, Barry’s Bootcamp and Charlotte’s Book, Amina is currently in the midst of writing Busy Happy Healthy’s first book.