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The Gut-Brain Axis: Nourishing a Path to Better Mental Health

There is a two-way communication system between our gut and our brain. If we don't have an optimal gut environment, then our mental health may suffer!

Image of healthy digestive tract without leaky gut

You have probably experienced the gut-brain connection at some point in your life. Have you ever been nervous about something and felt a flutter or pain in your stomach? That's the brain affecting the gut.

On the other hand, if you have gut health problems such as Irritable Bowel Syndrome (IBS), then you are three times more likely to have either anxiety or depression. This is an example of how the gut affects the brain. It is estimated that 50-90% of IBS sufferers have a mental health disorder of which anxiety or depression is the most prevalent.

Current data indicates that 21 percent of Americans have a mental illness, which equates to approximately 50 million people. Anxiety and depression are two of the most prevalent mental health problems and tend to be underreported. As research continues to provide a better understanding of the gut-brain connection, we are learning that improving gut health can not only improve digestion, but may also have a positive effect on our mental health.

What is the gut-brain axis?

The gut-brain axis is a symbiotic relationship between our gastrointestinal tract and our brain. This intricate network of communication involves neurons, hormones, and biochemical signaling pathways, which enables constant talking between these two organs. Trillions of microbes, known as the microbiota, play a role in this communication and have a significant influence on our mental wellbeing and general health.

Gut Health and Mental Wellness

Serotonin is a neurotransmitter responsible for regulating mood and happiness. It was once thought that the majority of the body's serotonin is produced in the brain. However, current research has shown that approximately 95 percent of serotonin is produced in the gut with certain bacteria playing a key role in its production. The risk for depression increases when a person has an imbalance in gut bacteria with low amounts of the microbes required to produce sufficient serotonin.

Another neurotransmitter called GABA (gamma aminobutyric acid) regulates mood by promoting a calm feeling and is also produced in the gut. Research has shown when there is an imbalance of gut bacteria, GABA production may be low and contribute to anxiety.

Nutrition: The Key to Nurturing the Gut-Brain Axis

The foods we choose to eat hold significant power in shaping our gut microbiota, and therefore our mental health. By following an eating pattern that supports the gut-brain axis, we can create a positive influence on the balance of our gut bacteria and optimize our mental health and wellbeing. Here are key dietary principles to promote a thriving gut-brain axis:

  1. Embrace a Mediterranean-style Diet: The Mediterranean diet, known for its numerous health benefits, has been consistently linked to lower rates of depression, heart disease, diabetes, and certain cancers. It is rich in vegetables, fruits, whole grains, legumes, nuts, fish, and olive oil while limiting red meat consumption. Moderate amounts of fermented dairy foods, such as yogurt and cheese, may also me included. This dietary pattern supports both gut health and mental wellbeing.

  2. Prioritize Gut-Friendly Foods: The foods that make up the Mediterranean diet, including vegetables, fruits, whole grains, legumes, nuts, fish, and olive oil, are known to support a healthy gut and microbiome. These nutrient-rich choices also nourish brain function and mental health by providing essential vitamins, minerals, and phytonutrients.

  3. Support a Balanced Microbiome: Maintaining a healthy balance of gut microbes is crucial for mental health. The presence of "good" bacteria in abundance and a limited number of "bad" bacteria promote optimal digestion, strong immune function, and mental health balance. Including gut-friendly probiotics (healthy bacteria) and prebiotics (food for gut microbes) in your diet can help restore and maintain a balanced microbiome.

  4. Ensure Adequate Nutrient Intake: Deficiencies of certain nutrients have been linked to an increased risk of depression and anxiety. Make sure your diet includes essential nutrients such as vitamin D, vitamin B6, vitamin B12, folate, magnesium, selenium, zinc, iron, omega-3 fatty acids, and amino acids. If you exclude specific food groups, consider taking a high-quality multivitamin/multimineral supplement to prevent nutrient deficiencies. Consult a Registered Dietitian Nutritionist for a dietary nutrient evaluation if you are unsure whether or not your diet is providing sufficient amounts of these essential nutrients.

  5. Hydration and Lifestyle Factors: Stay hydrated by consuming at least 8-10 cups of water daily to support a healthy intestinal environment. Dehydration can lead to constipation which over time may promote gut microbial imbalances. Additionally, incorporate stress management techniques into your daily routine, engage in regular physical activity, and spend time outdoors to further nurture a balanced gut-brain axis.

The Bottom Line

If you experience symptoms of depression or anxiety, seeking proper healthcare advice from your physician is essential for diagnosis and treatment. Alongside professional guidance, making conscious choices about your diet can significantly contribute to better mood balance and overall health. By following a Mediterranean-style diet and incorporating foods that support gut health, you may reduce symptoms of depression and anxiety while potentially preventing these mental health disorders from occurring.

If you need help with incorporating diet and lifestyle strategies to support mood balance, consult a Registered Dietitian Nutritionist who is familiar with this area of research. You may also book an Introductory Call with Kirkman Nutrition to see if our programs/services can help you.


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