The Gut Brain Connection

diagram of the human intestinal tract


Most people are surprised to hear that almost 30% of the US population will experience significant periods of anxiety or depression in their lifetime.  What’s also not commonly known is the fact one’s gut health can significantly impact symptoms of anxiety and depression!

The gut microbiome contains 10 to 100 trillion microorganisms (microbes) in the human digestive tract.  These microbes secrete a profound amount of chemical messengers in the body, some of which, called neurotransmitters, are the same chemicals that regulate your brain activity and mood.  Research even suggests that these microbes secrete more neurotransmitters than our brain, suggesting that taking steps to promote a healthy gut microbiome can have a profound impact on mood regulation.

Below are 3 ways you can help nourish your gut microbiome to support better mood and mental health.

1. Eat a variety of fermented foods.

Fermented foods, such as sauerkraut, kombucha, sourdough, cultured dairy, and tempeh each contain their own unique blend of microbes.  Adding a couple of tablespoons per day of at least two different sources is best.  Helpful Tip: When purchasing fermented foods, make sure that the label states that the product is ‘unpasteurized.’ Pasteurization can kill the bacteria in the food.

2. Consume a daily source of prebiotics, like raw garlic, onion, and banana.

Prebiotics, or fibrous carbohydrates that our gut bacteria digest, can decrease the amount of the stress hormone, cortisol, that our bodies create!  Helpful tip: Check out the Bastyr Nutrition Pinterest site (BCNH Nutrition) at to get some prebiotic-full recipes for pesto, guacamole, smoothies, and more!

3. Consider taking a probiotic supplement.  

Particularly after antibiotic use that can kill many of our healthy gut microbes, our gut may need help repopulating.  Probiotic supplements full of active microbes can help this process.  Helpful tip: Quality is key; look for a supplement that has several strains of bacteria and at least 15 billion CFUs.

The significance of gut health has been the topic of much research lately.  Mental health is just one more reason to nourish your gut microbes along with optimal digestion, immunity, decreased inflammation, and more!  

By Alison Kouba, MS, Bastyr University, Dietetic Intern