The Vagus Nerve: Why It Matters for Your Health

You may have heard about the vagus nerve in the context of stress relief or nervous system health. It's become a popular topic, with vagus nerve "hacks" everywhere online. But most of this information is superficial, focused on quick fixes without explaining why this nerve matters so much.

The vagus nerve is the longest nerve in your body, and it's the primary pathway through which your brain communicates with your organs. It affects your heart rate, your digestion, your inflammation levels, your mood, and your ability to feel calm and connected. When it functions well, your body can rest, digest, and recover. When it doesn't, you may struggle with anxiety, digestive issues, chronic inflammation, and a persistent sense of being on edge.

Understanding the vagus nerve helps explain why certain symptoms cluster together, and it points toward what actually helps.

What Is the Vagus Nerve?

The vagus nerve is the tenth cranial nerve, running from your brainstem all the way down through your neck, chest, and abdomen. Its name comes from the Latin word for "wandering," because it travels so extensively through your body.

It originates in the brainstem and branches out to your inner ear, throat, heart, lungs, stomach, intestines, and other organs. About 80% of its fibers are sensory, meaning they carry information from your body back up to your brain. The remaining 20% carry signals from your brain down to your organs.

This makes the vagus nerve a two-way communication highway. Your brain is constantly receiving information about what's happening in your body, and your body is receiving instructions from your brain. The quality of this communication affects almost every aspect of your health.

The Vagus Nerve and Your Nervous System

The vagus nerve is the main component of your parasympathetic nervous system, the branch responsible for rest, digestion, and recovery. When the vagus nerve is active, your heart rate slows, your digestion activates, your muscles relax, and your body shifts into repair mode.

This is the opposite of the sympathetic nervous system, which controls your stress response. When you're in fight or flight, your sympathetic system is dominant. When you're calm and settled, your parasympathetic system, driven largely by the vagus nerve, takes over.

The term "vagal tone" refers to how well your vagus nerve functions. High vagal tone means your body can efficiently shift from stress into rest. Low vagal tone means you get stuck in activation, unable to settle even when the stressor has passed.

Research has shown that vagal tone is associated with better emotional regulation, lower inflammation, improved heart health, and greater resilience to stress. It's measurable through heart rate variability, and it can be improved with specific practices.

Polyvagal Theory: A Deeper Understanding

Dr. Stephen Porges developed Polyvagal Theory to explain how the vagus nerve creates different states in the body. According to this framework, the vagus nerve has two distinct branches that create different experiences.

The ventral vagal pathway is the newer, more evolved branch. When this pathway is active, you feel safe, present, and connected. You can engage socially, think clearly, and access creativity and compassion. This is the state where healing happens.

The dorsal vagal pathway is older and more primitive. When this pathway dominates, you feel shut down, numb, or collapsed. Energy drops, motivation disappears, and you may feel disconnected from yourself and others. This is a protective response to overwhelming threat.

Between these two vagal states is the sympathetic nervous system, which creates the fight or flight response. A healthy nervous system moves fluidly between all these states as needed. Problems arise when you get stuck, whether in chronic activation, chronic shutdown, or cycling between the two.

The goal of nervous system healing is to strengthen the ventral vagal pathway, building your capacity for safety and connection, so you can navigate stress without getting stuck.

What the Vagus Nerve Affects

Because the vagus nerve connects to so many organs, its function affects multiple systems in your body.

Digestion

The vagus nerve controls the movement of food through your digestive tract, the secretion of digestive enzymes, and the absorption of nutrients. When vagal function is impaired, digestion slows and becomes inefficient.

This is why stress affects your gut so directly. When you're in fight or flight, vagal activity decreases, and digestive function suffers. Chronic stress can lead to bloating, constipation, acid reflux, and conditions like irritable bowel syndrome. Many digestive issues that don't respond to dietary changes alone are actually nervous system issues.

Heart Rate and Heart Health

The vagus nerve acts as a brake on your heart, slowing it down and keeping it from racing unnecessarily. When vagal tone is low, your heart rate tends to be elevated even at rest, and your heart rate variability decreases.

Research has linked low vagal tone to increased risk of cardiovascular disease. Conversely, practices that improve vagal tone have been shown to benefit heart health.

Inflammation

The vagus nerve plays a key role in controlling inflammation throughout your body. It's part of what's called the "inflammatory reflex," a pathway through which your brain can detect and suppress excessive inflammation.

When vagal function is impaired, inflammation can become chronic. This matters because chronic inflammation is linked to virtually every major disease, including heart disease, autoimmune conditions, and metabolic disorders.

Mood and Emotional Regulation

The vagus nerve carries information from your gut to your brain, influencing neurotransmitter production and emotional states. About 95% of your serotonin is produced in your gut, and this gut-brain communication happens largely through the vagus nerve.

Low vagal tone is associated with depression, anxiety, and difficulty regulating emotions. Improving vagal function often improves mood, even when nothing else has changed.

Immune Function

Your vagus nerve communicates with your immune system, helping to regulate its activity. When vagal function is healthy, your immune system can respond appropriately to threats without overreacting. When vagal function is impaired, immune dysregulation becomes more likely.

Signs Your Vagal Function May Be Impaired

Because the vagus nerve affects so many systems, impaired function can show up in various ways.

You may have difficulty calming down after stress. Your heart rate stays elevated, your mind keeps racing, and you can't settle even when the situation has resolved.

You may have chronic digestive issues that don't respond fully to dietary changes. Bloating, constipation, acid reflux, or irritable bowel symptoms that persist despite doing "everything right."

You may feel disconnected from your body, like you're going through the motions without really being present. Or you may feel chronically numb or shut down, lacking motivation or energy.

You may have trouble with emotional regulation, feeling reactive or overwhelmed by situations that others seem to handle more easily.

You may have chronic inflammation or immune issues, including autoimmune conditions that seem to flare unpredictably.

Often these symptoms cluster together, because they share a common root in vagal function.

How to Support Your Vagus Nerve

The good news is that vagal tone can be improved. The vagus nerve responds to specific inputs, and consistent practice can strengthen its function over time.

Breathwork

Extended exhale breathing is one of the most direct ways to stimulate the vagus nerve. When you exhale longer than you inhale, you activate the parasympathetic response. Try inhaling for four counts and exhaling for six or eight. Even a few minutes of this practice can shift your nervous system state.

Cold Exposure

Cold water on your face activates the dive reflex, which stimulates the vagus nerve. You don't need an ice bath. Simply splashing cold water on your face, especially around your eyes and cheeks, can activate this response.

Vocalization

The vagus nerve runs through your throat, and vibration in this area stimulates vagal activity. Humming, singing, chanting, and even gargling can all tone the vagus nerve. These activities seem mundane, but they have real physiological effects.

Social Connection

The ventral vagal pathway is deeply tied to social engagement. Feeling safe with other people, making eye contact, having meaningful conversations, these experiences strengthen vagal function. Isolation tends to weaken it.

Acupuncture

Acupuncture directly affects the vagus nerve and the autonomic nervous system. Research has shown that specific acupuncture points activate parasympathetic responses and improve vagal tone. For many people, acupuncture provides a level of nervous system shift that's difficult to achieve with home practices alone.

What This Looks Like in Practice

A woman came to us at 47 with digestive issues that had worsened over the past several years. She had bloating after almost every meal, acid reflux that kept her up at night, and bowel movements that alternated between constipation and urgency. She'd tried elimination diets, probiotics, and digestive enzymes. Some things helped temporarily, but nothing resolved the underlying issue.

When we talked, more of the picture emerged. She slept poorly, waking several times a night. She described herself as someone who couldn't relax, always on to the next thing, mind always running. She'd been this way for as long as she could remember, but it had intensified in the past few years as she'd entered perimenopause.

Her digestive issues weren't primarily a gut problem. They were a nervous system problem. Her vagal function was impaired, and her body was stuck in a state of chronic activation that made proper digestion nearly impossible.

We started with weekly acupuncture focused on calming her nervous system and supporting vagal tone. The first few sessions, she noticed she could breathe more deeply by the end of treatment. Gradually, she began to feel something she hadn't felt in years: actually relaxed.

She added simple practices at home. Extended exhale breathing before meals. Humming in the car. Going to bed earlier and reducing screen time in the evening. None of it was complicated, but she did it consistently.

Her digestion improved within the first month. The bloating that had been constant became occasional. The acid reflux that had disrupted her sleep resolved almost entirely. Her bowel movements became more regular.

But the bigger shift was in how she felt overall. She was sleeping better. She felt less reactive, more able to handle stress without spiraling. She described it as finally being able to come down, something she hadn't known she was missing until she experienced it.

What had changed was her vagal function. Once her nervous system could actually shift into parasympathetic mode, everything else followed.

Read stories from others who have done this work →

Your Next Step

If you've been struggling with symptoms that don't seem to respond to targeted interventions, your vagus nerve may be the missing piece. Digestive issues, sleep problems, chronic stress, difficulty relaxing, these often share a common root in vagal function.

Improving vagal tone takes consistent practice, and for many people, it takes support. Acupuncture is one of the most effective tools we have for shifting the nervous system and improving vagal function.

Contact us at 212.432.1110 or info@fafwellness.com.