An Introduction to the Vagus Nerve

The vagus nerve is one of the most fascinating pathways in the human body.

It is the longest cranial nerve in the body, traveling from the brainstem and branching throughout the neck, chest, and abdomen. Along the way, it communicates with major organs, including the heart, lungs, and digestive tract.

The vagus nerve is a major component of the parasympathetic nervous system—the part of the autonomic nervous system involved in rest, digestion, recovery, and regulation. Just as importantly, communication travels in both directions. The brain communicates with the body, but the body also sends an enormous amount of information back to the brain.

The Vagus Nerve: Roots Beneath the Soil

I like to think of the vagus nerve as the roots of a tree. A tree’s roots reach into the soil, gathering water, nutrients, and information from the living ecosystem around them. They exist in relationship with bacteria, fungi, minerals, moisture, and countless other organisms.

The vagus nerve does something beautifully similar within us. Its branches reach throughout the body, gathering information from the organs and tissues and carrying much of that information back toward the brain.

The digestive system is especially important here. Our gut and brain are in constant communication through multiple pathways, including the vagus nerve, the immune system, hormones, and the gut microbiome. The microbiome doesn’t simply send messages directly through the vagus nerve, but the organisms living within our gut can influence signaling pathways that communicate with the nervous system.

Our bodies are not isolated systems. They are ecosystems, and the vagus nerve is one of the pathways helping those ecosystems communicate.

What Does the Vagus Nerve Have to Do With Regulation?

The vagus nerve is involved in parasympathetic activity, which supports functions such as digestion, heart-rate regulation, and recovery following activation. This doesn’t mean the vagus nerve is a magical switch that turns stress off. Our nervous system is much more complex than that.

Healthy regulation is not about being calm all the time. It is about having the flexibility to move through different states of activation and return toward a state where rest, digestion, connection, and recovery are possible.

Research has connected greater vagal activity and measures of vagal function with aspects of cardiovascular regulation, inflammation, emotional regulation, and social engagement. However, these relationships are complex, and vagal activity is only one part of a much larger nervous-system picture.

That distinction matters. We don’t need to think of the vagus nerve as something that is either “healthy” or “broken.” Instead, we can learn to support the many systems that communicate through it.

Stimulating the Vagus Nerve Can Be Simple

Supporting parasympathetic activity doesn’t always require an elaborate practice. Sometimes it can begin with very ordinary things: sunshine, meditation, prayer, chanting, laughter, movement, slow and comfortable breathing, time spent with people we feel safe with, nourishing food, and time outdoors.

These experiences can influence the nervous system through different pathways. Some may support parasympathetic activity, while others influence breathing, heart rate, attention, emotional regulation, sensory processing, or our perception of safety and connection.

There isn’t one magic vagus-nerve exercise. There are many ways to communicate safety to the body.

The Gut-Brain Connection

One of the most fascinating relationships involving the vagus nerve is the connection between the digestive system and the brain.

Fiber-rich foods nourish the microorganisms within our gut. Certain types of fiber are fermented by gut microbes, producing compounds such as short-chain fatty acids that can influence immune, metabolic, hormonal, and nervous-system signaling.

Mushrooms can also contribute to a diverse diet because many contain unique fibers and polysaccharides that interact with the gut microbiome.

And then there is the simple experience of eating. As we eat and digest, signals from the gastrointestinal tract communicate with the brain about nutrients, distension, and satiety. The vagus nerve is one of the pathways involved in this communication.

Our gut is constantly talking, and our brain is constantly listening.

What About Probiotics?

The relationship between probiotics and the nervous system is an emerging area of research. Some animal studies have found that particular probiotic strains can influence behavior and nervous-system signaling through pathways involving the vagus nerve. Lactobacillus rhamnosus JB-1 is one example that has been studied in this context.

But we should be careful about turning promising research into a promise. What happens in an animal model does not automatically translate into the same effect in humans, and probiotic effects can be highly strain-specific.

This is one reason I love learning about the gut-brain connection. There is still so much we don’t know.

Connection Is Medicine for the Nervous System

Our nervous systems don’t exist separately from our relationships. Feeling connected, supported, seen, and safe with other people can influence autonomic regulation and emotional well-being.

Nurturing relationships can create closeness. Laughter can change our breathing and physiology. A hug, when welcome, can communicate connection. A conversation with someone we trust can help us feel less alone. Sometimes, simply sitting beside someone we love is enough.

These experiences aren’t just emotional. They are embodied. Our bodies experience relationship.

Laughter, Breath, and Sound

Laughter naturally changes our breathing pattern and engages the muscles of respiration. Practices involving slow breathing can also influence heart-rate variability and autonomic activity.

Meditation, prayer, chanting, humming, and singing are often used as ways of slowing down, regulating breathing, creating rhythm, and turning our attention inward. These practices may influence autonomic regulation, including pathways involving the vagus nerve.

But again, we don’t have to force our bodies into relaxation. The goal isn’t to perform the perfect vagus-nerve exercise. The goal is to create an environment where the nervous system has an opportunity to shift.

Sometimes that means breathing. Sometimes it means movement. Sometimes it means laughing until your stomach hurts. Sometimes it means sitting quietly in the sunshine. Sometimes it means being held by someone you trust.

What About Sunshine?

Sunlight has profound effects on human physiology. Light influences our circadian rhythms, sleep-wake cycles, mood, hormones, and many other biological processes.

Getting appropriate daylight exposure—especially earlier in the day—can support healthy circadian signaling and help anchor our daily rhythms. There are also emerging areas of research exploring relationships between light exposure, autonomic function, and nervous-system regulation.

But we don’t need to expose ourselves to unsafe amounts of UVA or UVB light in an attempt to “stimulate” the vagus nerve. More sunlight isn’t necessarily better.

A little time outside, allowing our eyes and body to experience natural daylight, moving our bodies, breathing fresh air, and noticing the world around us can be enough. Sometimes the simplest practices are the ones we actually return to.

Coming Back to the Roots

The vagus nerve reminds us that nothing in the body exists completely on its own. The brain communicates with the gut, and the gut communicates with the brain. The heart responds to emotion. Breathing changes with our state. Movement changes our physiology. Relationships affect how safe or connected we feel. Food interacts with our microbiome, and our environment continually gives our nervous system information.

We are constantly receiving messages from the world around us and from the ecosystem within us.

Maybe that is why I love thinking of the vagus nerve as roots. Roots don’t force a tree to grow. They create a relationship with the soil. They receive, respond, and connect.

Perhaps supporting our nervous system can begin in much the same way—not by forcing ourselves to be calm or trying to fix our bodies, but by learning to listen, breathe, nourish, move, connect, spend time in nature, laugh, rest, notice, and come home to ourselves.

The vagus nerve is only one piece of an incredibly complex system, but it gives us another beautiful way to understand just how deeply connected we really are.