Fitness coach Mark Schneider, NASM-CPT, recently worked with a client with a stubborn, mysterious pain. “She had an ongoing foot-ankle issue for several months that was starting to inhibit her ability to walk,” says Schneider, who’s trained in functional medicine and specializes in helping clients with injuries and chronic pain.
Her doctors hadn’t been able to find anything physically wrong. Schneider suggested various exercises, but nothing seemed to help — until they tried a relatively new tool for transcutaneous vagus nerve stimulation, or tVNS. For this treatment, the client wore an illuminated, headband-shaped device around her neck, where it delivered electrical stimulation through the skin to both sides of her vagus nerve for 20 minutes at a time.
“We were using the tVNS to address her emotional stress and general anxiety,” Schneider says. “Surprisingly, when she got up, her ankle wasn’t hurting anymore.”
Her pain disappeared after the first session. Months later, it still hasn’t returned.
It’s long been known that stress, anxiety, depression, physical pain, and inflammation can work together in self-reinforcing feedback loops. Researchers are now recognizing the vagus nerve as a key mechanism underlying those connections — and they’re studying how vagus nerve stimulation (VNS) can help.
“There are or have been nearly 500 clinical trials around the world looking at how stimulating the vagus nerve can help with medical conditions in which inflammation plays a critical role,” says functional-medicine physician Gregory Plotnikoff, MD. Those trials have examined issues including psychiatric concerns, neurodegenerative conditions, gastroenterological problems, and more.
Yet there’s no reason to wait for the outcomes of clinical trials to start harnessing the benefits of vagus nerve stimulation for stress relief. These are available to anyone.
The Vagus Nerve, Explained
The vagus nerve runs from your brainstem to nearly every organ in your body — from the heart and lungs to the gallbladder and spleen, all the way down to the depths of the digestive tract.
The body’s longest cranial nerve, the vagus is like a telephone line connecting distant parts of a rural community. It conveys messages between the brain and the body’s essential systems, keeping the organs functioning smoothly and carrying their information back to the brain. This bidirectional communication allows the brain to adjust bodily processes in real time, responding to activity, nourishment, and the need for rest.
The vagus nerve is part of the autonomic nervous system (ANS), which regulates heart rate, blood pressure, respiration, digestion, immune function, and metabolism. The ANS has two primary arms: The sympathetic arm is associated with the fight-or-flight response; the parasympathetic arm, dominated by the vagus nerve, is associated with the rest, digest, and restore mode. (A third branch, called the enteric nervous system, is located in the intestine and typically communicates with the brain through the vagus nerve.)
Functional-medicine provider Navaz Habib, DC, compares the two main branches of the ANS to the gas and brake pedals of a car. Both need to operate strongly and smoothly for maximum well-being.
“Without an accelerator — the sympathetic branch of the ANS — we would be unable to move efficiently and effectively through life. Without a brake pedal — the parasympathetic branch of the ANS — we would be unable to slow down, control our movements, and stop when necessary,” Habib explains in his book Upgrade Your Vagus Nerve.
The fight-or-flight response can get a bad rap, but it is crucial for daily life. It prepares the body for strenuous physical activity by increasing blood flow and improving oxygen delivery to the lungs. And it is not only the body’s accelerator, notes functional neurologist Jeremy Schmoe, DC, DACNB: “The sympathetic system allows your nervous system to tolerate stress.”
The parasympathetic system acts as the brake with the help of the vagus nerve. It assists in regulating the heart rate, stimulating digestion, and relaxing the breath, all of which downshifts an activated stress response. It allows us to self-soothe.
“A healthy vagus nerve keeps you calm in stressful situations and lets you know when danger is gone. This allows your body to rest and repair itself,” writes somatic therapist Anna Ferguson, CCATP, in The Vagus Nerve Reset: Train Your Body to Heal Stress, Trauma, and Anxiety.
After periods of prolonged stress or anxiety, it’s common to have some trouble activating the parasympathetic response. When we’re stuck in fight-or-flight, techniques that stimulate the vagus nerve manually can help slow and eventually stop the stress response.
“VNS is a game-changing therapy that helps to push on the brakes, allowing the body to begin the healing process,” says Habib.
An Extinguisher for Inflammation
One crucial function of the vagus nerve is to dial down inflammation in the body. This occurs through the cholinergic anti-inflammatory pathway, explains Plotnikoff.
When the vagus is stimulated, it sends electrical signals along its length. These lead to the release of acetylcholine, a neurotransmitter that regulates inflammation.
Acetylcholine interacts with specific receptors on immune cells, inhibiting the production of proinflammatory proteins called cytokines. Reducing proinflammatory cytokine production can lower inflammation not just locally but throughout the body. When we’re in fight-or-flight mode, the vagus nerve isn’t being stimulated, so it can’t send these important inflammation-reducing signals.
“This pathway is the functional relay circuit between the nervous system and the immune system — the neuroimmune system,” says Habib. This relay plays a key role in conditions characterized by widespread inflammation, such as rheumatoid arthritis or inflammatory bowel diseases (IBD). It’s why stress is linked with higher inflammation and worse symptoms in so many conditions.
It’s also why VNS is so promising for any condition worsened by stress in which inflammation plays a role.
Understanding Vagal Tone
The fitness of the vagus nerve is described as its “tone.” This determines how effective it is in regulating the stress response, among other things.
“It’s like water pressure in the shower,” explains Habib. When pressure is too low, the water can’t rinse away dirt or soap. Too high and it’s overpowering. “We want nice, strong, comfortable pressure. That’s good vagal tone — it’s strong enough to send signals to all the cells it needs to communicate with.”
Low vagal tone can lead to difficulty relaxing, poor digestive function (often with bloating and constipation), frequent infections, mood instability, and chronic inflammation. High vagal tone is associated with excess passivity in the body, as with the freeze response to stress. This is indicated by bradycardia (a too-slow heart rate), nausea, fainting, and respiratory problems.
Good vagal tone is neither high nor low; its sweet spot is right in the middle. This contributes to healthy digestion, stress resilience, a rightsized immune response, and reduced risk of inflammatory diseases.
Vagal tone is influenced by a variety of factors, including genetics, nutrition, exercise, breathing patterns, sleep, and environmental toxins.
Stress is also a major factor, Habib says, and it usually falls into one of four categories:
- Physical stress, such as overtraining, chronic inactivity, physical injury, or illness.
- Biochemical stress, such as exposure to environmental toxins or lack of adequate nutrition.
- Emotional stress in our relationships.
- Psychological stress, including past traumas that “scuff the lens through which we see the world,” Habib says.
“All those stressors force us to push the accelerator. When we try to slow down, we push the brake,” Habib explains. “If there’s too much stress over time, the vagus nerve [starts] to wear out and lower vagal tone.”
With some deliberate effort, however, we can restore healthy function of the parasympathetic system and strengthen vagal tone. This is what VNS techniques allow us to do.
Improving Vagal Tone With VNS
Heart-rate variability (HRV) — the time between individual heartbeats — is one of the best measures of vagal tone. A healthy heart doesn’t beat like a metronome; its rhythm varies by hundreds of milliseconds as the sympathetic and parasympathetic systems engage in a dynamic push and pull.
Chronically stressed people tend to have low HRV, writes Sara -Mednick, PhD, in The Power of the Downstate. “This represents a system stuck on overdrive and unable to flexibly respond to life’s demands and then appropriately calm the system down.”
Our HRV and vagal tone are highly responsive to daily experience, and we can influence them positively when we take good care of ourselves. Several lifestyle habits have an outsized impact, including time in nature; regular, high-quality sleep; a varied whole-foods diet; regular exercise; and routine social connection.
When these interventions are not available — or are not enough on their own to regulate the nervous system, as with illness or the aftereffects of trauma — vagal tone can also be enhanced through direct stimulation of the nerve.
Physicians first used modern electrical VNS in the 1980s to treat epileptic seizures; the U.S. Food and Drug Administration approved implantable electrical stimulation devices for epileptic patients in 1997. In recent years, research into noninvasive versions of this technology has expanded.
“The technology is not a cure for any particular condition at all,” explains Habib. “It is a device meant to help create a state shift.”
Studies of VNS suggest it can effectively treat symptoms of depression, anxiety, migraine, stroke, traumatic brain injury, PTSD, Parkinson’s disease, and Alzheimer’s disease. Long COVID clinics have deployed VNS to help relieve fatigue, brain fog, and anxiety.
Because the vagus nerve is central to the gut–brain connection, VNS may be a promising treatment for gut-related conditions, such as irritable bowel syndrome and IBD. “When gut function is compromised, the vagus nerve tends to be the first area that needs to be turned on in order to regulate and support overall health,” says Habib.
A 2023 report published in Bioelectronic Medicine found transcutaneous auricular vagus nerve stimulation — a type of tVNS via the ear — improved symptoms and inflammatory markers in a small group of children and young adults with mild to moderate IBD. A 12-month pilot study looking at surgically implanted VNS found that it restored healthy vagal tone and reduced inflammation in a group of seven patients with Crohn’s disease.
Noninvasive VNS devices are increasingly available without a prescription. Some are designed to be used on the ear, where electrical pulses stimulate the vagus nerve in the brainstem. Others can be held directly against the neck (like the one Schneider used with his training client), where a substantive part of the vagus nerve sits near the surface.
“Noninvasive VNS results in a quick improvement in vagus-nerve signaling,” says Habib. He’s seen a startlingly fast response in his patients who were previously unable to shift from sympathetic to parasympathetic states.
Though not a cure-all, VNS can help restore a sense of balance and calm, says Plotnikoff. Particularly for those with low vagal tone, who may have struggled with chronic stress and inflammation for years, it can provide a kick-start to the body’s relaxation response. This offers proof to the body and mind that another state is possible.
VNS can even be used during an acute stress response or panic attack, says Schmoe. By activating the parasympathetic nervous system, VNS helps the body counteract the surge of adrenaline and cortisol. This enables the return to a regulated state.
The one time to avoid using VNS, says Habib, is when the body is in a freeze response. This is signaled by fainting, low heart rate, or a general lack of affect. These symptoms are a clue that the parasympathetic system is overactivated, and VNS could make matters worse.
How to Activate the Vagus Nerve
The following techniques all safely stimulate the vagus nerve, but people with severe asthma, sleep apnea, or heart conditions should use caution with any electrical forms of VNS.
1. Practice long, slow exhalations. Slow breathing helps activate the vagus nerve. Simply slowing the breath and increasing the length of your exhalations can stimulate the parasympathetic response.
2. Immerse your face in cold water. When you plunge your face into cold water or splash some on your face, it stimulates a natural reflex called diver’s reflex, which slows the heart rate.
3. Hum, chant, sing, or gargle. Try gargling water for 30 seconds in the morning and evening, right after you brush your teeth. Activating the muscles around the vocal cords can stimulate electrical activity along the vagus nerve, says Habib.
4. Use an isometric hold. Isometric holds can act as a kind of nervous-system reset. “Holding a lunge or a squat, strongly gripping the hand, or doing a Valsalva maneuver [bearing down while pushing breath out against your sealed nose and mouth] can quickly release and calm the nervous system,” Schmoe says.
5. Try transcutaneous vagus nerve stimulators. Handheld or wearable tVNS devices specifically include the Pulsetto and Truvaga. Some are designed for use on the ear; others target one or both sides of the cervical branch of the vagus nerve in the neck.
6. Apply transcutaneous electrical nerve stimulators. TENS units are typically used to treat pain by delivering electrical currents to targeted areas, but they can be used off-label to stimulate the vagus nerve. Follow the guidance of a health professional to ensure safety.
7. Get ARPwave. This is a type of neuromuscular electrical stimulation mainly used by physical therapists for pain relief and muscle re-education. These are typically found only in therapeutic settings.
8. Explore implanted vagus nerve stimulators. Surgically implanted stimulators are FDA-approved only to treat epilepsy and treatment-resistant depression. Research is ongoing to explore their potential for several other conditions, including migraine, rheumatoid arthritis, and IBD.
Habib recommends practicing some method of VNS twice daily — upon waking and right before bed. “I like bookending the day with it,” he says. “It’s great for helping people become alert and in a state where they can handle things in the morning. And it’s wonderful for helping people sleep, [and] sleep is the gym for the vagus nerve.”
In short, a VNS practice can help you keep calm and carry on. Who among us doesn’t need a little more of that?
How to Measure Your Vagal Tone
The most precise metric for assessing vagal tone is heart-rate variability (HRV), says functional-medicine provider Navaz Habib, DC. A healthy heartbeat is not perfectly symmetrical; the rhythm varies slightly as the sympathetic and parasympathetic systems engage in a dynamic push and pull. HRV measures the time between individual heartbeats.
High HRV (more variance between heartbeats) corresponds to greater vagal tone, while low HRV suggests an overactivated sympathetic response and lower vagal tone. A number of large studies indicate that a robust HRV is predictive of a range of positive health outcomes, including a lower risk of type 2 diabetes and heart disease. It also corresponds to sharp cognition and emotional regulation.
Many devices on the market measure HRV, including watches, chest straps, and even rings to track trends and patterns. But there are also several tech-free ways to dial into your vagal tone.
One is the palatine-arch response test. The ability to lift the soft palate is directly linked to the effective function of the vagus nerve. Try depressing your tongue with a toothbrush and looking at the uvula in the back of your throat in a mirror. Observe how the arches framing your uvula move as you say, “Ahh.”
Ideally, the arches lift symmetrically, and the uvula points straight down. If the arches don’t rise or rise unequally, or the uvula points toward one side, it can indicate vagus nerve impairment.
If the vagus nerve can’t effectively lift the soft palate, your voice may have a nasal or monotone quality — another indicator of poor vagal tone.
The most accessible window into vagal tone is simply checking in with how you feel. In general, can you meet the demands of your day and then let them go? Or do you find yourself ruminating, feeling simultaneously tired and wired, and struggling to self-soothe?
“At its core, a regulated nervous system is a resilient nervous system,” explains somatic therapist Anna Ferguson, CCATP, in The Vagus Nerve Reset. “Burnout, illness, and chronic pain are all manifestations of a stressed nervous system.”
This Post Has 5 Comments
I think anyone that is going to stimulate their vagus nerve in the neck needs to discuss this with an MD. As an RN, I need to see more research as to how this is something a layman would do to themself.
Great article and practical advice.
Loved it!!!
This article was startling to me. Why would you have an article on vagal stimulation? It’s extremely dangerous to do on your own. It is performed in a hospital setting for supraventricular tachycardia (SVT), for example. Massaging the neck (carotid) should be done in a hospital setting with an EKG monitor. Do you have a response as to why you would think this is something someone should do to relax? They could relax themselves to a heart rate of 30.
Terrific article. And such an important topic! Excited to share this one with my Healthy Deviant community. Thank you!