The Gut-Brain Axis

If you’ve been following along in the world of health and wellness over the last decade or so, you may have noticed a phrase popping up everywhere: the gut-brain axis. Researchers are calling it a groundbreaking discovery. Headlines declare it a “revolutionary” new understanding of how the body works. Here in the world of East Asian medicine, we’re reading those headlines with a warm smile and maybe — just maybe — a little knowing nod.

Because friends, we’ve been talking about this for about 2,000 years! Well, maybe not us at Jennum O’Hara Acupuncture, but practitioners of East Asian medicine in general.

Welcome to That’s What We’ve Been Saying! — a series where we explore the places where cutting-edge Western science and ancient East Asian medicine arrive at the same destination, just a couple of millennia apart. No shade, only love (and a little collegial ribbing). Western medicine and research are doing important and beautiful work. If I have a major emergency, I’m going to the nearest hospital, not calling my acupuncturist! We’re just glad everyone is finally starting to get space at the table.

So, What Is the Gut-Brain Axis?

In modern science, the gut-brain axis refers to the constant, two-way communication happening between your digestive system and your brain. Through the vagus nerve, the enteric nervous system (sometimes called “the second brain”), hormones, and the gut microbiome, your gut and your brain are in continuous conversation — influencing each other’s function in ways that researchers are only beginning to fully understand.

Some of what they’ve found is remarkable. The gut produces roughly 90–95% of the body’s serotonin — yes, the “feel-good” neurotransmitter most people associate with the brain. Disruptions in gut health have been linked to anxiety, depression, brain fog, and mood disorders. Stress, in turn, directly affects digestion, gut motility, and the health of the intestinal lining. The relationship flows both ways, all the time, without us ever thinking about it.

Western medicine is now building entire fields of research around this connection. And it is genuinely exciting science.

It’s just not new information — at least not to us.

What East Asian Medicine Has Always Known

East Asian medicine has always viewed the body as an integrated whole. There is no separation between mind and body, emotion and physiology. They are one system, always in conversation, always influencing each other. Sound familiar?

Let’s look at a few specifics:

The Spleen-Stomach network and the mind

**Important to note: When we say an organ name, we are not talking about the organ. Well, at least not ONLY talking about the organ. We are discussing a whole system and network. If you hear an acupuncturist say something about your spleen, your organ is likely just fine! They are talking about the system and channel, which encompasses many more structures and functions than just your spleen organ! If you have concerns about the organ itself, talk to your physician. You can tell us, too, but your physician is the one who can appropriately consider your concerns in that realm.

In East Asian medicine, the Spleen and Stomach are the central organs of digestion — responsible for transforming food and fluids into the nourishment the body needs. But their role was never purely physical. Classical texts describe the Spleen as governing Yi — thought, intention, and the capacity for mental focus. When the Spleen is depleted or out of balance, patients don’t just experience digestive symptoms like bloating, fatigue, or loose stools. They experience mental fogginess, worry, overthinking, and an inability to concentrate.

Sound like anyone you know who’s been dealing with gut issues and brain fog at the same time? East Asian medicine didn’t see those as two separate problems. It never did.

The Heart and the Small Intestine

In Western anatomy, the heart and small intestine seem like an odd pairing. In East Asian medicine, they are a coupled organ system — connected by meridian pathways and understood to influence each other deeply. When a patient comes in with anxiety, or other concerns of emotional wellbeing, palpitations – potentially considerations of the heart in EAM – and digestive trouble – possibiliy attributed to concerns with the small intestine in EAM – an East Asian medicine practitioner doesn’t raise an eyebrow. Of course those things are connected.

Emotions live in the body

Perhaps the most fundamental alignment between EAM and the gut-brain axis research is this: East Asian medicine has always recognized that emotions are physiological events, not just mental ones. Each organ system is associated with particular emotional states. The Liver with frustration and anger. The Lung with grief. The Spleen with worry. The Kidney with fear.

This isn’t metaphor — it’s clinical observation built up over centuries. When patients are chronically stressed or grieving, their digestive function changes. When their gut is struggling, their emotional resilience suffers. Treating one always involves considering the other.

I often use the following examples to explain this to people. Have you ever felt nervous about something and just thinking about it caused you to noticed physical sensations in your stomach as a result? Butterflies or knots? Or have you stubbed your toe and had an emotional reaction to the physical sensation? We know this is true from our lived experience.

Modern neuroscience is now confirming what practitioners have observed in clinic for millennia: that the gut and the brain are not separate systems having separate problems. They are partners.

Why This Matters for You

If you’ve ever noticed that your stomach goes haywire when you’re anxious — or that a rough patch with your digestion leaves you feeling emotionally flat and foggy — you are experiencing the gut-brain axis firsthand. Your body has been trying to tell you something that both ancient medicine and modern science agree on: these things are connected.

This is also why East Asian medicine can be so effective for conditions that don’t seem obviously “digestive.” Anxiety, depression, insomnia, and chronic stress all have physical roots — and the gut is often part of that story. Likewise, digestive complaints like IBS, bloating, and nausea almost always have an emotional and nervous system component worth addressing.

Treatment in East Asian medicine — whether through acupuncture, herbal medicine, dietary therapy, or qi gong — has always worked with both dimensions simultaneously, because from our perspective, they were never separate to begin with.

A Note of Genuine Gratitude

Here’s the thing about Western research catching up to ancient wisdom: it’s actually wonderful. It means more people get access to this understanding. It means integrative care becomes easier to justify, easier to recommend, and easier to receive. It means patients who might never have walked through an East Asian medicine clinic door might start to see their gut, their brain, their emotions, and their body as the unified, intelligent system they truly are.

So while we might be smiling warmly at headlines that feel very familiar, we welcome every study, every paper, and every curious researcher with open arms.

We’ve been saving you a seat at the table for 2,000 years.

Interested in supporting your gut-brain connection through East Asian medicine? Schedule now

This blog is part of the series “That’s What We’ve Been Saying!” — exploring the places where ancient East Asian medicine and modern Western science meet. Stay tuned for future installments.