Gut Check #7: The Gut Brain Connection

Welcome to Gut Check by Beny Yogurt 👋 If you’re new here, you can check out previous editions on our site anytime. 

The gut is often referred to as your second brain. Turns out, there’s some scientific basis behind phrases like “go with your gut” or “gut feeling”. The gut-brain axis is a complex communication network with entire books dedicated to the topic. Here’s a high-level look at how it works and why it matters.

The Gut Brain Axis: How Your Gut and Brain Communicate

The gut-brain axis is a two-way communication highway between your microbiome and brain. Lining your gut are specialized cells that produce over 20 hormones and neurotransmitters, including dopamine, serotonin, and GLP-1 (the active ingredient in Ozempic—yes, a healthy gut naturally produces GLP-1). In fact, over 90% of your body’s serotonin, key to mood, sleep, and appetite, is made in the gut.

When these gut cells detect nutrients, they release neurotransmitters that travel through the bloodstream and up a pathway called the vagus nerve, sending signals directly to the brain.

What this Means for Mental Health

Nearly 1 in 4 U.S. adults, around 60 million people, experience a mental health disorder. Research shows a strong link between gut inflammation and mental health issues. Patients with depression often have elevated inflammation, and more than half of those with chronic gut disorders like Crohn’s or IBS also experience anxiety and depression.

In one study, volunteers without depression willingly received injections of LPS (lipopolysaccharide), a gut-derived toxin that triggers inflammation. Within hours, they developed depressive symptoms like anxiety, dark moods, and cognitive impairment.

With two-thirds of Americans reporting digestive issues, could gut inflammation be a root cause of the mental health crisis?

It’s hard to argue that food doesn't affect our emotions. Just compare how you feel after eating a balanced dinner with protein, veggies, and carbs versus a basket of fries. Your microbiome processes, breaks down, and digests food, fueling everything from energy levels to brain function.

What can you do?

A meta-analysis of randomized controlled trials found that gut-focused interventions—like diet changes and probiotics—improved mood disorders in 30-40% of cases. In other words, fixing your gut could help improve mental health.

Kiki and I first connected in an undergraduate class at Stanford taught by Christopher Gardner. He, in partnership with the Sonnenburg Lab, studied how diet impacts gut health, measuring microbiome diversity and inflammatory markers before and after dietary interventions. In a 10-week trial, participants followed either:

1. A high-fermented food diet: ~6 servings/day of fermented foods like yogurt, kefir, kimchi, etc.

2. A high-fiber diet: ~45g/day of fiber from foods like legumes, seeds, nuts, vegetables, etc.

The results were fascinating. The high-fiber group saw no significant changes in microbiome diversity or inflammation. But the high-fermented food group showed both increased microbiome diversity and decrease in inflammation. 

The takeaway? Try to incorporate fermented foods daily to increase microbiome diversity, lower inflammation, and ultimately, boost your mood

Top of Mind

✈️ Expo West: We brought Beny on its first field trip out to California for Expo West this week - if you’ll be here come say hi to us (slide into our DMs).

🥣 Beny in the Wild: Events are ramping up – we did a pop up with Superpower at Verci, a Sunday morning walk with Lime Social and Brooklyn Walk Club, and a pop up at Apollo bagels. If you want to stay informed on future events, join our starter crew and subscribe to our event calendar.

🍽️ Supper Club: We’re co-hosting a dinner party with Dial C on March 15th - only 6 spots available, throw your name in the ring. 

🎤 Pod: Learn a bit more about what it’s like to start a business with your Bestie in this article on Hustled or listen to this podcast. 

Have a great week!

Elan and Kiki (The Yogurt Girls)