The Gut-Brain Connection: How What You Eat Affects How You Feel

The relationship between the gut and the brain is one of the most exciting frontiers in nutritional science. Research published in journals including Nature and Cell over the past several years has fundamentally changed our understanding of the gut microbiome — the trillions of bacteria, viruses and fungi that inhabit the digestive tract — and its far-reaching effects on mental health, immune function and chronic disease risk. The gut is increasingly referred to as the ‘second brain,’ housing over 100 million neurons and producing approximately 90 percent of the body’s serotonin.

Diet is the primary driver of gut microbiome composition. A fiber-rich dietary pattern built around whole plant foods feeds beneficial gut bacteria and promotes a diverse, resilient microbiome. Studies have found that greater microbiome diversity is associated with lower rates of depression, anxiety and inflammatory conditions. Fermented foods — yogurt, kefir, sauerkraut, kimchi and kombucha — introduce beneficial live bacteria that further support microbiome health. Conversely, diets high in ultra-processed foods, refined sugars and artificial sweeteners have been shown to reduce microbial diversity and promote inflammatory species.

Practical steps to support a healthy gut this fall include increasing your intake of prebiotic foods (garlic, onions, leeks, oats, bananas) that feed beneficial bacteria, eating more fermented foods and reducing ultra-processed food consumption. Managing stress and prioritizing sleep also support gut health, as the gut-brain axis runs in both directions — meaning psychological stress directly affects gut microbiome composition. This is an area we find endlessly fascinating, and one where our NutriGreene team can offer meaningful, evidence-based guidance.

Sources

• Cryan JF, et al. The microbiota-gut-brain axis. Physiol Rev. 2019;99(4):1877-2013.

• Valles-Colomer M, et al. The neuroactive potential of the human gut microbiota in quality of life and depression. Nat Microbiol. 2019;4(4):623-632.

Ready to take the next step in your nutrition journey? Schedule an appointment at NutriGreene today. www.nutrigreene.com | (203) 429-4211 | info@nutrigreene.com