What Is the Vagus Nerve — and Can Breathwork Really Stimulate It?

Your longest cranial nerve is connected in more ways than you think.

A lot of ink has been spilled about the benefits of breathwork because of how it stimulates the vagus nerve. If practicing breathwork like Box Breathing, among other techniques, accomplishes its intentions by manipulating the vagus nerve to positively affect your heart rate and, as a result, your mood and capacity to concentrate, then it seems the vagus nerve is pretty important. Well, what is it?

What Is the Vagus Nerve?

The vagus nerve, which derives its name from the Latin for “straying” or “wandering,” and is referred to as the “wandering nerve,” is the longest cranial nerve, extending from the medulla oblongata in the brainstem through the neck and thorax to the splenic flexure of the large intestine — the sharp bend in the upper left abdomen. It comprises 75% of the parasympathetic nervous system, which operates the automatic functions of your body, like breathing and digestion.

The parasympathetic nervous system is one of two nervous systems. The other is the sympathetic nervous system, which automates the functions necessary for the body to operate during intense physical demand. You might have heard it referred to as the “fight or flight” response.

The vagus nerve is made up of afferent and efferent fibers. Afferent is Latin for “bringing toward” and refers to the sensory neurons that transmit signals to the brain and comprise approximately 80% of the vagus nerve. Efferent is Latin for “to carry out” and refers to the nerve cells that transmit information from the brain to parts of the body.

Put more simply, if a nerve cell is sending information to the brain, it’s afferent. If it carries information away from the brain — out to the body — it’s efferent. The majority of the vagus nerve (i.e., afferent fibers) transmits signals from the gut, liver, heart, and lungs to the brain.

How Does Breathwork Influence the Vagus Nerve?

Put simply, breathwork doesn’t influence the vagus nerve as much as it aims to manipulate it. Diaphragmatic breathing, the slow and deep variations of breathwork, aim to modulate autonomic nervous functions (e.g., the afferent fibers signaling how the brain should respond to various stimuli).

Breathwork practices have been shown to reduce heart rate, which allows the vagus nerve’s afferent fibers to cue the brain to relax, thereby promoting better control over stress levels.

As with any practice, consistency is key. The best results are likeliest to come from consistent breathwork practice for sessions longer than five minutes. This can also be improved by human-guided sessions, so those meditation or yoga classes are probably worth your time.

The Takeaway

Breathwork can help you control what would otherwise be an automatic function in your body. It can enable you to arbitrarily lower your heart rate so the vagus nerve can signal the brain to calm down.

Effective breathwork is a continuous practice that requires consistent effort. So set aside a handful of minutes each day to check in with yourself, take some deep, rhythmic breaths, and perhaps some stress will melt away.