Activating this nerve can relieve stress. Here’s how to do it.

Whether you’re aware of it or not, there’s an information superhighway running down each side of your neck right now. And every time you take a long, slow exhale, you’re using that highway — an essential part of your nervous system — to bring your body into a calmer state. It’s called the vagus nerve. And the myriad ways this vast network of nerves supports your physical and mental well-being is nothing short of remarkable.

The vagus nerve is actually not a single nerve but a vast network of about 200,000 nerve fibers, said Kevin J. Tracey, president and CEO of the Feinstein Institutes for Medical Research at Northwell Health and author of The Great Nerve: The New Science of the Vagus Nerve and How to Harness Its Healing Reflexes. It starts with two nerve bundles that run from your brain down the sides of your neck and into the torso — where they touch organs such as your heart, lungs, intestines, spleen, liver, and pancreas.

Here’s what experts want you to know about the role the vagus nerve plays in your health, what the online hype gets wrong, and how to stimulate your vagus nerve at home.

The vagus nerve helps your body maintain a dynamic state of balance called homeostasis through constant brain-body communication. “It is working every second to control things reflexively that you don’t think about,” Tracey said, such as your heartbeat, breathing, digestion, and immune system activity (also known as inflammation). This is foundational to good health — because severe or ongoing imbalances in these reflexive functions contribute to many disease states, he said.

If your heart starts to race, for example, vagal nerve fibers sense that increase and alert the brain, which in turn sends messages down the vagus nerve telling your heart to slow down. (About 80% of the nerve fibers sends signals up from the body to the brain, Tracey said, while the other 20% sends information the other way.)

The vagus nerve also plays a key role in nervous system regulation. Many people these days spend too much time in the stress response or fight-or-flight response, said Mill Etienne, a professor of neurology at the New York Medical College School of Medicine and director of neurology at WMCHealth’s Good Samaritan Hospital. In this state, heart rate, breathing, cortisol levels, and inflammatory markers spike.

“That chronic stress activation wears and tears on the body over time,” said Christopher Wallace Austelle, a psychiatrist at Stanford Medicine who has studied vagus nerve stimulation. It’s the equivalent of straining your car’s engine by constantly having your foot on the accelerator. The vagus nerve functions as the body’s “brake pedal” by enacting the relaxation response or “rest-and-digest” state, Etienne said — dropping heart rate, breath pace, cortisol, and inflammation.

A nervous system that can efficiently switch between these states as needed and be in the relaxation response more often — exhibiting what’s called high vagal tone — is linked to greater well-being, Tracey said. Low vagal tone, on the other hand, is associated with chronic stress, higher levels of inflammation, and diseases such as heart failure and hypertension.

Doctors sometimes prescribe a device-assisted medical treatment called vagus nerve stimulation (VNS). Surgically implanted devices (placed in the chest and neck) are approved or cleared by the Food and Drug Administration for specific conditions, including epilepsy that doesn’t respond to medication, treatment-resistant depression, obesity, and post-stroke motor rehabilitation. There are also newer, less studied noninvasive VNS devices (placed on the neck or the ear), approved for conditions such as drug-resistant migraines and tinnitus.

While scientists are still figuring out how exactly these devices work, one popular theory is that VNS triggers the relaxation response and increases vagal tone, Austelle explained. This may in turn activate anti-inflammatory pathways, Etienne added, and put the brakes on chronic inflammation — a known driver of many chronic conditions, including autoimmune disease, Type 2 diabetes, cancer, Alzheimer’s disease, and heart disease.

The vagus nerve has become a hot topic on Instagram lately. “I am glad that it’s trending on social media, because it is very important to understand how this vagus nerve impacts your overall health and life,” Etienne said. But most of the social media content on the vagus nerve is “very oversimplified,” Tracey cautioned. “It’s more complicated and more interesting, frankly, than is usually represented online.”

There are also claims about the health-boosting powers of commercially available noninvasive VNS devices you can buy without a prescription. But there isn’t much research on VNS in people without medical conditions, and these devices have not been validated in clinical trials, Austelle said. “So there is some skepticism in the field about some of these at-home stimulation modalities.”

Some small studies show that prescription-only noninvasive VNS can reduce the stress response and increase the relaxation response in healthy individuals, Austelle said. (One 28-person study found that a week of daily 30-minute use improved cardiovascular fitness and postexercise inflammation, while the placebo “sham” device did not.) But long-term effects are unclear, he said.

The risk of side effects is low, Austelle said, and some people may indeed benefit. “But there’s not enough data for me to confidently say you should be doing this at home on your own,” he said. “The field is still too young.” He recommends consulting a doctor who knows your health history.

What about various natural ways of supposedly stimulating the vagus nerve, such as breathwork or cold-plunging? Can they provide the same payoff as medical VNS?

While these activities involve some vagal nerve fibers, comparing them with a medical VNS device is misleading because they don’t target the nerve in that same high-powered way, Tracey explained. “To call that vagus nerve stimulation is a misnomer at best.”

That said, certain activities can help improve your vagal tone, especially when done consistently over time, Etienne said. Here are the ones experts recommend:

Exercise: One common misconception is that the vagus nerve is stimulated only in conjunction with the relaxation response or calming activities. But the vagus nerve is equally active during exercise, Tracey said — when the body is under stress. “One of the best ways to increase your vagal tone is to engage in exercise,” Etienne said. Aerobic exercise has been shown to trigger vagal activity, Tracey said. And we know that people who exercise consistently tend to have a lower resting heart rate and better heart rate variability, Etienne points out — associated with higher vagal tone.

Breathwork: Various types of deep-breathing exercises have been shown to affect some of the same markers that VNS devices do, Austelle said. A 2025 research review found that certain types of breathwork significantly increase the nervous system’s relaxation response activity and vagal tone, as well as emotional control — while at the same time, reducing cortisol levels, stress, and anxiety. The types of breath practices validated in this research were all slow (taking six or fewer breaths per minute), diaphragmatic (inhaling from deep in the belly, instead of the chest), and through the nose. Etienne often recommends simple box breathing to his patients, where you inhale, hold the breath in, exhale, and hold the breath out all for an equal amount of time (usually four seconds).

Meditation: People sometimes notice their heart rate slow down during meditation, Tracey said. “Because my heart rate is slowing down, the fibers in my vagus nerve that go to my heart have been stimulated,” he explained. It’s not clear whether it’s the meditation practice itself, or the way people may breathe while meditating (usually more slowly and deeply) that is affecting the vagus nerve, Tracey said. Either way, research shows that mindfulness meditation is linked to the relaxation response, a lower resting heart rate, and higher heart rate variability, all indicators of high vagal tone.

Cold exposure: While the idea that cold plunges improve vagal tone is popular, this one is not as well-studied, Tracey said. Some small studies suggest cold exposure on the face increases vagal activity, including under stress, possibly through the effects of the cold on heart rate and breathing.

Overall, none of these practices offer the same powerful vagus nerve stimulation as a medical device. But they do have the benefit of being free, time-tested, and generally excellent for your overall health. “You end up getting additional benefits that just using a device might not give you,” Etienne said. “So you’re changing your overall internal milieu, as opposed to just doing a quick fix.”

Because despite what you might see online, vagus nerve stimulation is no magic bullet. An at-home VNS device or breathwork routine is not going to undo the effects of a poor diet or chronically high stress levels, Etienne pointed out.

But the vagus nerve is undoubtedly powerful — and scientists are excited to learn more about how to use it to improve our health. “I am very optimistic about the potential of harnessing the functions of this nerve,” Austelle said. “But we’re only starting to scratch the surface of what we can really do.”