A Quickguide to the Vagus Nerve By Sophie Knapp MScN, CN

August 01, 2023

A Quickguide to the Vagus Nerve By Sophie Knapp MScN, CN

You may have heard of it, the parasympathetic, the rest & digest, the gut brain, the great wanderer… What I’m talking about that one, single nerve that’s so impactful on your overall wellbeing, the vagus nerve. 

If you’re feeling stressed or burnt out, if your digestion is whack or you’re constantly getting sick, if you can’t sleep at night and you’re easily triggered all day, then this gigantic nerve wandering through much of your body likely needs your attention. 

Gigantic and wandering is no exaggeration; the latin roots of it’s name, vagus, translate to “wander.” The nerve itself spans a large portion of your body, beginning in your brain, it travels all the way down to the intestines, innervating all the organs of the digestive tract, the diaphragm, the salivary glands, and more.

But to understand the vagus nerve, you need to understand its context. Zoom out. We’re talking about a nerve here, so let’s first understand the section of your nervous system it belongs to--Autonomic Nervous System (ANS). The nerves in this system function without you ever having to think about them, and they control things like your intestines, heart, lungs, immune system, and more. 

Although this part of the nervous system doesn’t require your conscious attention to function, it can be influenced by your thoughts and actions. More on that later...

The ANS has two parts:

One is called the sympathetic nervous system. This part is active when you’re in fight or flight, and it manifests as feelings like a sense a urgency, fear, stress, overwhelm, and/or sadness.1 The vagus nerve is very inactive when the sympathetic nervous system is lively.

The other side is the parasympathetic, and the vagus nerve comes to life when this side of the ANS is firing signals. When in a parasympathetic state, you’re said to be in rest and digest. Feelings here manifest as calm, ease, contentment, and creativity.

The vagus nerve is key in the ANS and influences several of its functions including digestion, heart rate, ability to regulate mood, and the immune system i.e. inflammation levels.2 

Remember how focusing on this nerve can help address all sorts of issues like sleep, burn out, immunity, and digestion? Look at how many jobs it has!

By taking steps to improve its activation, you help so many of your body’s systems function more optimally, and when you’re functioning more optimally, you get sick less, feel fewer effects from stress, get better sleep, experience more positive emotions, and have more energy.

On the contrary, if the vagus nerve is inactive, then you’re spending lots of time in fight or flight, and that’ll make you feel stressed, burnt out, irritable, and make it difficult to sleep. You’ll have a heck of a time digesting your food without the vagus nerve stimulating your GI tract that, and you’re at a disadvantage in fighting infections.3

The great news is that simple actions can have a profound impact on how much vagal tone you have throughout the day. The key to success is consistency. 

Though periodic, short bouts of vagus-nerve-stimulating actions do have a scientific effect at turning down fight or flight while amping up rest and digest, taking these actions daily or several times each day is the key to keeping your vagus nerve toned up and active.

Try starting your day with one of these actions. Set reminders or add them to your schedule so you remember to do them.

Vagal tone works just like muscle tone. The more you work it, the more it’ll work for you!


Simple Actions to Stimulate the Vagus Nerve:


Slow, deep breathing.4,5 


4-7-8 breathing, specifically has been shown to decrease sympathetic nervous system activity while ramping up vagus nerve output.6 

Try on the 4-7-8 breathing technique. Starting your day by sitting upright on your bed, or move to the floor, and inhale for a count of 4, hold your breath for a count of 7, then exhale for a count of 8. Repeat for 3 cycles total. Over time, work your way up to doing 10 or more breath cycles like this. 

You can also turn to deep breathing, and any of these other simple actions, as a way to calm down when something triggers your sympathetic nervous system. Someone cuts you off in traffic, breathe. You just got bad news, breathe. You’re about to eat a meal, breathe. Heading to bed, breathe.


Meditation. 

This can mean sitting and observing your breath or following along with a guided meditation. 

 

Laughing, singing, and gargling.

Spend time with a friend, belt out the lyrics in your car, and yes, gargle some water for about 30 seconds. They all directly increase the firing rate of the vagus nerve.


Cold exposure.

Take cold plunges or cold showers. You don’t need to tell the world you’re doing it! Just try making the last 30 seconds of your shower cold next time you’re in there. Focus on staying calm. Focus on your breath and possibly a mantra like, “I am ok.”

Or you could just dip in the sound and maintain the same focus as you would in a cold shower. 


Find joyful movement. 

Exercise stimulates the vagus nerve and helps reduce inflammatory markers via actions of the nerve. Enjoy a form of movement that makes you happy and that feels good in your body daily. Yoga is such a powerful vagus-stimulating tool. You get to move and meditate at the same time, so you’re doing two actions on this list at once. Amazing!


Hone your nutrition to support a healthy microbiome and improve vagus nerve function.7–9 

Eat a diverse variety of fresh, whole, colorful plant foods, at least 30 unique ones each week. Eat lots of anti-inflammatory omega-3 fatty acids found in fatty fish, walnuts, and several seeds including flax, chia, and pumpkin. Limit inflammatory foods like processed, conventionally grown, and high-sugar foods. Consider taking probiotics.


Try these out one at a time, and allow them to accumulate if you can. You’ll thank yourself when you’re relishing in your restored vitality!

  1. Kop WJ, Synowski SJ, Newell ME, Schmidt LA, Waldstein SR, Fox NA. Autonomic nervous system reactivity to positive and negative mood induction: the role of acute psychological responses and frontal electrocortical activity. Biol Psychol. 2011;86(3):230-238.
  2. Breit S, Kupferberg A, Rogler G, Hasler G. Vagus Nerve as Modulator of the Brain-Gut Axis in Psychiatric and Inflammatory Disorders. Front Psychiatry. 2018;9:44.
  3. Thayer JF, Sternberg EM. Neural aspects of immunomodulation: focus on the vagus nerve. Brain Behav Immun. 2010;24(8):1223-1228.
  4. Banushi B, Brendle M, Ragnhildstveit A, et al. Breathwork Interventions for Adults with Clinically Diagnosed Anxiety Disorders: A Scoping Review. Brain Sci. 2023;13(2). doi:10.3390/brainsci13020256
  5. Fincham GW, Strauss C, Montero-Marin J, Cavanagh K. Effect of breathwork on stress and mental health: A meta-analysis of randomised-controlled trials. Sci Rep. 2023;13(1):432.
  6. Vierra J, Boonla O, Prasertsri P. Effects of sleep deprivation and 4-7-8 breathing control on heart rate variability, blood pressure, blood glucose, and endothelial function in healthy young adults. Physiol Rep. 2022;10(13):e15389.
  7. Browning KN, Verheijden S, Boeckxstaens GE. The Vagus Nerve in Appetite Regulation, Mood, and Intestinal Inflammation. Gastroenterology. 2017;152(4):730-744.
  8. Singh A, de la Serre C, de Lartigue G. Gut microbiota sPARk vagus nerve excitation. J Physiol. 2020;598(11):2043-2044.
9. Bonaz B, Sinniger V, Pellissier S. The Vagus Nerve in the Neuro-Immune Axis: Implications in the Pathology of the Gastrointestinal Tract. Front Immunol. 2017;8:1452.