The Vagus Nerve: The Central Organ of Your Nervous System and How to Stimulate It

In just a few years, thevagus nervehasbecome one of the most studied topics in integrative medicine—and for good reason. This 1-meter-long nerve, which runs from the brainstem down to the lower abdomen, is the main pathway through which your brain regulates your heart, lungs, digestion, immune system, and emotions. When it is toned, the body heals itself, sleep is deep, and anxiety subsides. When its tone drops,the entirebalance of the autonomic nervous systemisdisrupted.

This article explains exactly what the vagus nerve is, how it affects your health, how to recognize the signs of low vagal tone, and the 8 scientifically proven methods for stimulating it long-term.

What is the vagus nerve?

Thevagus nerve(from the Latinvagus, meaning “wandering”) is the tenth cranial nerve and by far the longest in the human body. It originates in the brainstem, at the base of the brain, and runs down each side of the neck to innervate nearly all the organs of the trunk: heart, lungs, larynx, pharynx, stomach, liver, spleen, kidneys, small intestine, and the first part of the colon.

Its name comes from its "wandering" path, which seems to meander throughout the body, in contrast to the other cranial nerves, which are confined to the head and neck. The vagus nerve is actuallya pair of twin nerves(one on each side), which together form the cornerstone ofthe parasympathetic nervous system.

Its most surprising feature:80% of its fibers travel from the organs to the brain, and only 20% travel from the brain to the organs. In other words, this nerve is primarily amessenger from the body to the brain—it constantly transmits the physiological state of the internal organs to the central nervous system. It is through this nerve that the bulk ofthemuch-discussedmind-body connection flows.

The Role of the Vagus Nerve in Your Health

The vagus nerve controls—directly or indirectly—an astonishing number of vital functions:

• Cardiac regulation: It slows the heart rate and increases heart rate variability (HRV), a direct indicator of cardiovascular health.
• Breathing: It regulates breathing depth and rate, and receives feedback signals from the lungs.
• Digestion: It stimulates the secretion of digestive juices, controls gastrointestinal motility, and regulates satiety.
• Immune and anti-inflammatory regulation: It activates theanti-inflammatory cholinergic pathway, which reduces low-grade systemic inflammation.
• Emotional regulation: It modulates the activity of the amygdala (fear), the anterior cingulate cortex (regulation), and the insula (interoception).
• Social connection: It controls the muscles of the face, larynx, and middle ear—the entire mechanism of expression and social communication.
• Blood sugar: It influences insulin secretion by the pancreas.
• Inflammation and healing: High vagal tone is associated with faster healing and less postoperative inflammation.

The key point is that all these effects occur througha single anatomical pathway. Stimulating the vagus nerve simultaneously affects all of these functions. This is why seemingly unrelated symptoms—such asanxiety,insomnia,high blood pressure, acid reflux, and chronic pain—often respond to the same mechanism.

Vagal tone: the hallmark of your nervous system health

Vagal tonerefers tothe baseline activity level of the vagus nerve. The higher it is, the more effectively the parasympathetic nervous system can restore the body to a state of calm after a stressful episode. The lower it is, the more the nervous system remains “stuck” in sympathetic alert mode—this is chronic dysregulation of the ANS.

Vagal tone is measured indirectly throughheart rate variability (HRV): the minute fluctuations in heart rate between two beats. The higher the HRV, the more active the vagal tone. The lower it is, the more rigid the nervous system.

High vagal tone is associated with:

• Greater stress resistance
• Better recovery after exercise
• Better deep sleep
• Better emotional regulation
• Less chronic inflammation
• Reduced cardiovascular risk
• Increased longevity (strong correlation in epidemiological studies)

Good news:vagal tone can be trained, just like a muscle. The review by Sevoz-Couche and Laborde (2022,*Neuroscience & Biobehavioral Reviews*) documents this plasticity—just a few weeks of practice are enough to observe a measurable increase in resting vagal tone.

Signs of a hypactive vagus nerve

Low vagal tonecannotbe measured spontaneously in the general population, but its effects are recognizable. If you experience several of the following symptoms and they have persisted for more than 3–6 months, your vagus nerve is likely underactive:

• High resting heart rate (typically > 70 bpm)
• Chronic anxiety, rumination, hypervigilance
• Light sleep, waking up during the night, persistent fatigue
• Slow digestion, bloating, sensitive stomach, acid reflux
• Chronic muscle tension (jaws, trapezius muscles, back)
• Difficulty "unwinding" after a stressful day
• A feeling of being constantly on alert
• Chronic inflammation (widespread pain, inflammatory fatigue)
• Increased susceptibility to infections (weakened immune system)
• Difficulty crying, laughing heartily, or feeling moved (parasympathetic numbness)

None of these symptoms is specific on its own. It isthe combinationof these symptoms thatshould raise a red flag—and this is precisely the picture ofchronic dysregulation of the autonomic nervous system, at the heart of which lies underactivation of the vagus nerve.

How to Stimulate the Vagus Nerve: 8 Scientifically Proven Methods

There aremany ways tostimulate the vagus nerve. All of them activate the same parasympathetic pathway. Here are the eight best-documented methods, ranked by the strength of the evidence.

1. Slow, deep breathing — the gold standard

Breathing at a rate of 6 cycles per minute usingdiaphragmatic breathing is by far the best-documented method foractivating the vagus nerve. At this frequency, breathing resonates with the cardiovascular baroreflex: the vagus nerve is stimulated at its peak efficiency (Sevoz-Couche & Laborde 2022). This is known ascardiac coherence. Its effects have been documented on anxiety (Lehrer 2020, 58 RCTs), depression (Tatschl 2020), hypertension (Cheng 2026), pain, and sleep.

2. Exposure to cold

Cold water on the face, a cold shower, or immersion in cold water: these trigger themammalian diving reflex, which acts directly on the vagus nerve and instantly slows the heart rate. A measurable effect on HRV within minutes. Tocalm the vagus nerveinacute situations (such as during apanic attack), this is one of the fastest techniques.

3. Singing, humming, gargling

The vibration of the larynx mechanically stimulates the branches of the vagus nerve that innervate the area. Singing, humming, chanting the vowel “om,” or simply gargling for an extended period are free ways to stimulate the vagus nerve that can be done anywhere. This practice, which has been used for thousands of years in meditative traditions, has been scientifically validated over the past decade.

4. Moderate-intensity endurance exercise

Brisk walking, cycling, swimming, or jogging at a conversational pace (you should be able to talk): 30 minutes a day significantly increases resting vagal tone. Avoid strenuous exercise, which mainly activates the sympathetic nervous system.

5. Mindfulness meditation

Several studies show an increase in HRV after 8 weeks of regular meditation practice. This effect is due in part to slower breathing and in part to changes in the brain regions of the limbic system.

6. Genuine social interaction and physical contact

Deep face-to-face conversation, eye contact, a long embrace, skin-to-skin contact: these stimulate the social pathway of the vagus nerve (Stephen Porges’ polyvagal theory, see below). This is no small matter: it is a major regulatory pathway that is particularly underutilized in the digital age.

7. Quality sleep

During deep sleep, vagal tone reaches its natural peak. Poor sleep deprives your nervous system of the time it needs to regulate itself. A screen-free period starting at 10 p.m., a cool bedroom, and a regular sleep schedule are non-negotiable essentials. For thosewith stress-related insomnia, a breathing exercise in the evening can help restore this balance.

8. Transcutaneous auricular nerve stimulation (tVNS)

Recent devices (auricular) electrically stimulate the auricular branch of the vagus nerve through the skin. This is a promising method that is still undergoing clinical evaluation. It should not be confused with surgical VNS (an implanted device used to treat epilepsy or treatment-resistant depression), which remains a major medical procedure.

Methods 1, 2, 7, and 6 are the most accessible and best documented for the general public. Deep breathing remains the most effective on its own, because it isthe only parasympathetic function over which we have direct voluntary control.

Deep breathing: the best-documented method

Why does breathing hold a special place among methods for stimulating the vagus nerve? There are three reasons:

• It’s somethingyoucan control directly.Youcan’t just decide to slow down your heart rate, digestion, or body temperature. But you can slow down your breathing—and by doing so, you activate the vagus nerve, which regulates everything else.
• It exploits a peak in physiological efficiency.At6 cycles per minute (0.1 Hz), breathing resonates with the cardiovascular baroreflex. The vagal signal to the brainstem is at its maximum at this frequency, and only at this frequency.
• It is measurable.The effecton heart rate variability, cortisol, and blood pressure is immediate and reproducible. This is what makes it the most extensively studied method—with over 100 RCTs and 5 major meta-analyses published in the past 10 years.

The regimen that brings about a lasting change in resting vagal tone has been documented:15 to 20 minutes a day for 4 to 12 weeks. It is this 20-minute regimen that we call Deep Vagal Breathing™. Full scientific details are available onour Science page.

The Vagus Nerve and Anxiety

Chronic anxietyisone of the most common clinical manifestations of low vagal tone. The mechanism is as follows: when the vagus nerve is underactive, the sympathetic nervous system remains dominant, the amygdala (the brain’s fear center) becomes overactive, and the alarm threshold is lowered. Even the slightest stimulus triggers a disproportionate anxiety response.

Vagal stimulation through breathing restores the amygdala to a normal level of activation. The benchmark meta-analysis (Lehrer 2020, 58 randomized clinical trials) documents an effect on anxiety “comparable to established treatments”—precisely because the mechanism addresses the root cause, not the symptom. For individuals with anxiety, a daily breathing practice is the best-documented non-pharmacological intervention.

The Vagus Nerve and Depression

The link betweenthe vagus nerve and depressionisone of the most robust findings in neurobiology over the past 20 years. Several studies have shown that patients with depression have, on average, significantly lower heart rate variability than the general population—a sign of impaired vagal tone.

Conversely, vagus nerve stimulation produces a measurable antidepressant effect.Surgical VNSisofficially indicated for treatment-resistant depression. And non-invasive vagal stimulation through breathing produces significant effects in patients with depression: the study by Tatschl and Schwerdtfeger (2020) in a psychiatric setting measured a significant effect (d = 0.79) on depressive symptoms after 5 weeks of HRV biofeedback.

Depression should never be treated on your own. However, as a complement to medical care, deep breathing exercises are a powerful tool—with no side effects—that works on the underlying nervous system.

The vagus nerve and chronic inflammation

One of the most promising discoveries of the past decade concerns theanti-inflammatory cholinergic pathway: when the vagus nerve is active, it releases acetylcholine in the spleen, which inhibits the secretion of pro-inflammatory cytokines (TNF-α, IL-6) by macrophages. In practical terms: an active vagus nerve reduces low-grade systemic inflammation.

This approach is currently being explored as a potential treatment for rheumatoid arthritis, Crohn’s disease, irritable bowel syndrome, and certain autoimmune disorders. For the general public without any underlying medical conditions, high vagal tone maintained through deep breathing contributes tooverallinflammatory resilience—a key factor in aging healthily.

The vagus nerve and the polyvagal theory

Thepolyvagal theory, proposed by American neuroscientist Stephen Porges in the 1990s, has profoundly transformed our understanding of the vagus nerve. It distinguishes between two branches:

• The dorsal vagus nerve, the evolutionarily older branch, which controls the freeze and immobilization responses to an imminent threat.
• The ventral vagus nerve, a recently evolved branch (in mammals), which governs social engagement, communication, and connection—as well as cardiac and respiratory regulation.

According to this theory, nervous system health depends largely onstimulating the ventral vagus nerve—through breathing, but also through genuine social interaction, the human voice, eye contact, and prosody. This understanding has revolutionized the treatment of trauma, post-traumatic stress disorder, and anxiety-depressive disorders by systematically incorporating the physical and relational dimensions.

The Neoflo Belt: Strengthen the vagus nerve in just 20 minutes a day

TheNeoflo breathing beltwasspecifically designed tostimulate the vagus nervethroughbreathing, at just the right intensity, without requiring any mental effort. Three haptic motors placed on the abdomen guide your breathing through touch—no screen, no app. You start the session, close your eyes, and 20 minutes later, your vagal tone has been re-trained.

L'étude de Bouny et al. (2023, revue Sensors) a démontré que le guidage tactile produit un index de cohérence cardiaque deux fois supérieur au guidage visuel (0,55 vs 0,28, p < 0,05). Et la position abdominale de la ceinture exerce en plus un rappel proprioceptif continu sur le diaphragme — le muscle qui, en mobilisant les viscères, sollicite mécaniquement le nerf vague.

The Neoflo belt comes with an 8-week guidance program—the standard duration of the clinical trials that measured changes in resting vagal tone. Designed by a biomedical engineer (Philippe Cortès) and a physician specializing in sleep and mental health (Dr. Thomas Cantaloup). Bronze medalist at the 2024 Lépine Competition.

30-day "money-back guarantee" trial period, with free shipping and returns.

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FAQ — Nerf Wave

What is the vagus nerve, and what does it do?

The vagus nerve is the tenth cranial nerve and the longest nerve in the human body. It runs from the brainstem down to the organs of the trunk (heart, lungs, stomach, and intestines). It is the main pathway ofthe parasympathetic nervous system: it controls recovery, digestion, heart regulation, emotional calm, and the anti-inflammatory response. 80% of its fibers travel from the organs back to the brain—it is the primary messenger of the mind-body axis.

How can I tell if my vagus nerve is underactive?

Low vagal tone cannot be directly measured in the general population, but its signs are recognizable: a resting heart rate > 70 bpm, underlying anxiety, light sleep, functional digestive disorders, chronic muscle tension, and difficulty unwinding after a stressful day. The presence of several of these signs over a period of more than 3–6 months is a clear sign of parasympathetic dysregulation.

What are the best ways to stimulate the vagus nerve?

The 5 most accessible and best-documented methods: (1)slow breathing at 6 cycles per minute(the most effective on its own), (2)exposure to cold(cold water on the face, cold shower), (3)singing, humming, gargling(laryngeal vibration), (4)moderate endurance exercise, (5)quality sleep. Combine these for maximum effect. Deep breathing is the gold standard because it is directly controllable and the most studied.

Can you strengthen your vagus nerve through daily habits?

Yes, that is precisely the approach that yields lasting results. Vagal tone can be trained like a muscle. A daily 20-minute practice ofcardiac coherence, combined with adequate sleep, a 30-minute daily walk, and regular exposure to cold, produces a measurable increase in vagal tone within 4 to 8 weeks (Sevoz-Couche & Laborde 2022).

The vagus nerve and anxiety: what's the connection?

Chronic anxietyisone of the most direct manifestations of low vagal tone. Mechanism: underactive vagus nerve → overactive amygdala → lowered alarm threshold → disproportionate anxiety responses. Vagal stimulation through breathing restores the amygdala to a normal level of activation. The 2020 Lehrer meta-analysis (58 RCTs) documents an effect on anxiety “comparable to established treatments.”

Does the vagus nerve play a role in depression?

Yes, this link is very well documented. Depressed patients have, on average, significantly lower heart rate variability—a sign of impaired vagal tone. Vagal stimulation produces an antidepressant effect: surgical VNS is officially indicated for treatment-resistant depression. Non-invasively, deep breathing produces a measurable effect: the 2020 Tatschl study measures a significant effect on depressive symptoms (d = 0.79). It is not a substitute for treatment, but a serious adjunct.

What are the effects of overstimulating the vagus nerve?

This is very rare with non-invasive methods. Deep breathing, cold temperatures, or singing do not cause overstimulation in a healthy person. Acute parasympathetic hyperactivation may cause dizziness, a feeling of wobbly legs, a temporary drop in blood pressure, or drowsiness—none of which are serious and resolve when the person stands up slowly. Implanted electrical VNS, however, can have side effects (voice changes, coughing) that are managed medically.

Are there any electrical vagus nerve stimulators?

Yes.Surgical VNS(vagus nerve stimulation) is a surgically implanted medical device used to treat refractory epilepsy and treatment-resistant depression. Transcutaneousauricular VNS is a newer, non-invasive approach currently undergoing clinical evaluation. For the general public, natural methods (breathing, cold, singing) produce vagal stimulation with comparable regulatory effects, without the need for a medical device.

How long does it take to feel the effects of regular stimulation?

Immediate effects (slowed heart rate, calmness) starting with the first session.Lasting change in resting vagal tone: 4 to 8 weeks of daily practice at a rate of 20 minutes per day. Effects onmental load, anxiety, and sleep: generally 2 to 4 weeks. Effects on physiological markers (blood pressure, inflammation): 8 to 12 weeks.

Stimulate your vagus nerve, restore your body's natural balance

Thevagus nerveisthe central hub of your nervous system—the one that regulates, repairs, and soothes. Strengthening it through daily practice means holding in your hands one of the most powerful levers of your physical and mental health. TheNeoflo beltmakesthe practice simple and sustainable in daily life—screen-free, requiring no mental effort, guided by touch, and at a scientifically validated intensity.

Discover the Neoflo belt → 30-day “satisfaction guaranteed or your money back” trial, with free shipping and returns.

neoflo is a wellness tool. It is not a medical device and is not intended to replace medical advice, diagnosis, or treatment. If you have persistent symptoms or a known medical condition, consult a healthcare professional.