Why the vagus nerve is the key to fighting stress

The vagus nerve plays a critical role in stress regulation and feelings of safety, according to both Brad Lichtenstein, ND, BCB, at The Breath Space in Lake Forest Park, Wash. and Courtney Snyder, MD, a holistic psychiatrist in private practice in Louisville, Ky.

Known as the "great wandering protector” of the body, it starts in the brain stem and extends all the way down through the colon, affecting most body systems, according to a 2017 article in Gastroenterology. Like a superhighway, it transmits information back and forth from our organs to our brains and vice versa.

“The vagus sends signals down to the body to help regulate digestion, heart rate, and blood pressure, inflammation, and more. It also sends signals back up to the brain about what is happening in the body,” said Lichtenstein.

According to Lichtenstein, vagal tone — the health of the vagus nerve — is reflective of the ability to relax, which is a critical counterbalance to sympathetic nervous system arousal (“fight or flight”). It’s an important marker of the parasympathetic nervous system, or the “rest and digest” state.

“The vagus plays a crucial role in our ability to regulate and adapt to stress by detecting what is happening in the body and determining if we are safe enough to rest and repair,” said Lichtenstein.

The vagus nerve acts as a brake for the nervous system, explained Stephen Porges, PhD, in "Stress and Parasympathetic Control," a chapter in "Encyclopedia of Neuroscience," 2009. Vagal braking lowers our heart rate and blood pressure, helps us sleep and digest our food, and even helps us relax enough to socialize with others, he said.

Significant health problems can occur when we’re stuck in a state of sympathetic dominance, also known as “chronic stress.” Stress is the common risk factor for 75 percent to 90 percent of diseases, including those which cause the foremost morbidity and mortality, according to a 2017 study in Frontiers in Human Neuroscience.

“Because the vagus nerve is connected to almost all of our organs, most of our body systems can be impacted by our being in a chronic sympathetic state,” said Snyder.

On the other hand, any actions that can be taken to support the vagus nerve can have a far-reaching positive impact.

“It’s the one thing that connects all the dots as far as helping lower inflammation, promoting detoxification, assisting with the functioning of the organs, helping people with mindfulness, and lowering chronic stress in their life,” Snyder said.

According to Snyder, low vagal tone can result from a wide range of experiences. Anything that creates chronic emotional stress, such as trauma and early childhood adversity, can negatively impact the vagus nerve. Mold toxicity and microbial overgrowths such as a tooth abscess can be damaging on a physiologic level, while structural damage can occur from excessive alcohol use and injury.

Signs that may point to low vagal tone include chronic inflammation, gastrointestinal conditions, and psychiatric symptoms such as anxiety and depression, said Snyder.

Both Snyder and Lichtenstein agreed that one compelling aspect of the vagus is its relation to  feelings of safety. Snyder said that the vagus nerve picks up information that our conscious minds can’t register and relays it to the brain. Lichtenstein said that phenomena like “gut feelings” may actually be the vagus nerve at work detecting changes in the body as a response to threat. If we’re feeling threatened regularly, our vagal tone will reflect that.

“Vagal activity, vagal breaking, and vagal tone reflect our degree of psycho-emotional-physiological and even socioeconomic, political safety,” said Lichtenstein

According to Snyder, we don’t have to be stuck in a war zone for our bodies to register a lack of safety. Day-to-day life is enough to keep us in a state of arousal that blocks our vagal brakes. According to Lichtenstein, holding your breath, tightening your abdominals, and clenching your muscles are all signs that you’re in a state of fight or flight.

“I think everyone tends to think they feel safe and associates not feeling safe with someone who has PTSD,” said Snyder. “But our daily stressors actually impact our sense of safety through the vagus nerve.”

Toning the vagus nerve

The vagus can be toned with a variety of methods. Breathwork is one of the most well-documented, according to a 2018 study in Frontiers in Human Neuroscience. As we tone the vagus, we positively influence the systems it regulates.

“Every time we exhale, the vagus nerve sends a signal down to the heart, and it slows it down instantly,” said Lichtenstein.

He said that slow breathing with a long exhale is particularly effective, as the vagus is activated during the exhale. The longer the out-breath, the more time it has to activate. “When you exhale slowly, you really let those nerves fire,” he explained.

Snyder said that since the vagus is linked to the vocal cords, singing, chanting, and even gargling are effective ways to tone it. She added that postural changes may also activate it, which means yoga, dance, and tai chi can also be beneficial. Doing just one of these activities for even 20 minutes a day could be helpful.

“If people aren’t going to focus on many things, putting focus on something like meditation or a breathing practice could be far-reaching,” Snyder advised.

Lichtenstein believes that taking care of our vagus nerve may require a change in lifestyle.

“Are we eating when we’re in front of the T.V. or when we’re in our car or at our desk? Then we’re in sympathetic. Then we’re not only not digesting our food, but we’re not toning our vagus at all,” he said.

He emphasized that while vagal brakes such as breathwork are helpful, a commitment to reducing stress on a daily basis would be more beneficial.

“It’s an orientation to life,” he said.

Brittany Vargas is a writer, trauma-informed journalist, and holistic healing practitioner who is passionate about mind-body medicine. She has held diverse roles in the communications field and has reported on wellness, travel, culture, lifestyle, and local news. As a copywriter, she helps conscious companies, lifestyle entrepreneurs, nonprofits, and Fortune 500 companies grow their audiences and influence. Brittany has a fifteen-year-long yoga and meditation practice and is an avid student of several complementary medicine modalities.