If there is one part of the nervous system worth getting to know, it is the vagus nerve.
The word "vagus" comes from Latin, meaning "wandering." It was named this because of how it wanders through the body, branching out from the brainstem and travelling through the face, throat, heart, lungs, and into the digestive system. It is the longest cranial nerve in the body, and it carries information in both directions: from the brain down to the organs, and from the organs back up to the brain.
The vagus nerve is the main pathway of the parasympathetic nervous system, the rest-and-digest branch we talked about earlier. When it is active and healthy, it helps the body do many essential things, including:
In other words, the vagus nerve is one of the body's main tools for coming back down after stress.
When the vagus nerve is functioning well, the body can shift more easily between activation and rest. This is sometimes called having good vagal tone. Research has linked stronger vagal tone with better physical health, better emotional regulation, better sleep, better digestion, and even better recovery from illness.
When the vagus nerve is under-functioning, the body has a harder time returning to calm. Stress lingers. Sleep is harder. Digestion may suffer. Emotions feel harder to manage.
Vagal tone is not something a woman is simply born with or without. It can be strengthened, gently, over time, with daily practices that send the right signals through the nerve. We will explore those practices in the next article.
Researchers measure vagal tone using something called heart rate variability (HRV), the small natural variations in time between heartbeats. Higher HRV is associated with stronger vagal tone and a more flexible, resilient nervous system.
You do not need any equipment to begin supporting your vagus nerve. But if you ever hear someone talk about HRV in the context of stress or wellness, this is what they are referring to.
Polyvagal Theory describes the vagus nerve as central to all three nervous system states.
When you are in the safe and connected state, one branch of the vagus nerve is active and supporting calm engagement with the world.
When you are in fight or flight, the vagus nerve quiets down so the sympathetic nervous system can take over and mobilise the body.
When you are in shutdown, an older branch of the vagus nerve takes over in a different way, conserving energy and helping the body essentially "play dead" until the threat passes.
This is why so much of nervous system work focuses on the vagus nerve. It is one of the body's main switches between these states.
What is genuinely encouraging is that the vagus nerve is responsive. It listens to the body. When you breathe slowly, hum softly, splash cold water on your face, or rest in a moment of true safety, the vagus nerve gets the message. Over time, with repeated small practices, the system learns to settle more easily.
This is not magical thinking. It is biology. The next article will walk through the practical tools.
You do not need to understand every detail of how the vagus nerve works to benefit from caring for it. You just need to know that there is a real, physical pathway in your body whose job is to help you come back to calm, and that this pathway responds to the small, consistent things you do every day.
Your body has built-in mechanisms for healing. The work is to give them the conditions they need.