The Gut Brain Axis: How What You Eat Affects Your Mood

Do you ever listen to your gut feeling?

Your gut and your brain have a communication system called the gut-brain axis.

This communication pathway is a two way street, meaning that your gut speaks to your brain and regulates its activity just as frequently as your brain speaks to and regulates the activity within your digestive tract.

How your microbiome plays a role

While there are several different channels through which these two systems speak to one another, the bacterial colonies within the gut microbiome appear to be the primary communication director. The microbiome refers to the numerous colonies of bacteria that reside within the gut, primarily in the colon. These bacteria assist us by helping us break down otherwise indigestible carbohydrates. They also regulate many crucial systems within the body including the immune system, digestive system, and central nervous system (the central nervous system includes the brain and spinal cord). This means that if you are looking for a diet that will support lifelong physical and mental health, it’s important to eat foods that will nourish your microbiome.

Fiber feeds your microbiome

Recently low carb diets have grown in popularity, touted for their numerous health benefits including their ability to increase energy and mental clarity. And true, low carb diets do often correlate with an abundant intake of foods known to support cognitive function, such as avocados, olive oil, salmon, eggs, nuts, and seeds. Unfortunately though, a high fat, low carb diet may also be depriving your brain of certain foods needed to support emotional health.

For many years scientists have known that the intake of fiber and fermented foods supports gut health and, in particular, the health of the microbiome. It is also known that fiber is most abundant within carbohydrates such as grains, beans, and to a lesser degree within fruits and vegetables. This is why some health experts claim that carbohydrate intake is crucial for leveraging the diet as a tool to support physical, mental, and emotional health. In particular claims have been made that carbohydrate intake is necessary for the production of serotonin, one of our happy hormones. Additionally, there have also been recent claims that certain probiotics may help alleviate symptoms of anxiety and depression and improve overall mood.

An overview of the science

Here’s a closer look at the impact of diet on the microbiome and the impact of the microbiome on emotional health

  • The microbiome is affected by many different factors including diet and stress

  • Disturbances in the microbiome are increasingly being linked to the presence of allergies, auto-immune disorders, metabolic disorders and neuropsychiatric disorders including anxiety and depression

  • Research suggests that the bacteria in your gut communicate to your brain through the following different mechanisms:

  • Stimulation of the vagus nerve (a nerve responsible for down regulating our stress response)

  • Production of GABA, a hormone known to help control fear and anxiety

  • Production of serotonin, which regulates mood, memory, and sleep. In fact, 95% of serotonin is produced in your gut

  • Production of dopamine, which also helps regulates sleep, increases our attention and focus, increases motivation, supports learning, and allows us to feel pleasure

  • Excessive stress as well as diets lacking in fiber and probiotics can negatively impact the gut microbiome and cause what’s known as “dysbiosis,” an abnormal balance of bacterial communities in the gut

  • Stress can also cause the gut to become more “leaky,” allowing substances created by the gut bacteria to enter the bloodstream in abnormally high concentration. Researchers suggest that in high concentrations, these particles may exacerbate or cause symptoms of anxiety and depression

  • Certain bacterial species have been shown to effectively mediate stress responses and reduce symptoms of anxiety and depression. In particular, the following bacterial species are known to be beneficial:

  • Lactobacillus rhamnosus

  • Lactobacillus helveticus

  • Bifidobacterium infantis

  • Bifidobacterium longum

The Apeiron Life perspective

We are focused on supporting your long-term physical, mental, and emotional health. Although research regarding the microbiome is still relatively new, results strongly suggest that one of the best things you can do for your overall health is to eat a diet rich in whole grains, beans, fruits, vegetables, fermented foods, and healthy fats such as avocado, nuts, and seeds. These foods help the beneficial bacteria (mentioned above, plus others) to thrive - these plant fibers are their food sources. To incorporate these foods, aim for a Mediterranean Diet. By eating this way you will not only nourish your gut, but also provide your body with an abundance of other nutrients supportive of life long health.

Many factors influence emotional health and the manifestation of anxiety and depression. Although diet plays a role we can’t guarantee that dietary changes will make a significant difference in stress levels or emotional health. That being said, with the exception of those people with certain medical conditions such as IBD and compromised immune systems, all people can benefit from consuming a diet rich in fiber and probiotics. If you don’t enjoy fermented foods you can try taking probiotic supplements instead, which are generally recognized as safe. If you do have a condition or are taking medication that compromises the immune system make sure to speak with your doctor before consuming fermented foods or taking probiotics

Keep in mind...

The health effects of dietary changes aren’t always immediately apparent. If you are interested in utilizing diet to promote emotional well-being, we recommend gradually introducing more complex carbohydrates and fiber into your diet (introducing too much fiber too fast can cause digestive discomfort). As you make changes pay attention to how your energy, stress, anxiety and/or depression levels may vary based on dietary changes. The effect may be subtle, but through utilizing mindfulness you’ll gain a better understanding of how your body reacts to certain foods and how to best utilize diet to support your unique physiology.

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