How You Can Repair Your Vagus Nerves
Ross Hauser, MD
Anything that the body physiological knows is stressful will eventually damage the vagus nerve; likely anything the body physiological knows is there to give it health will strengthen the vagus nerve. Our bodies are smarter than our ego-centered lifestyles and that is, in large part, thanks to the work our vagus nerve does to keep our autonomic nervous system in check. The vagus nerve can also represent your “gut feeling” about something that you know sound like a bad, unhealthy, or dangerous idea. It is always trying to protect you! You want to optimize your vagal tone so it can keep helping you stay alive and thrive!
In this image we see that the vagus nerve protects us from emotional and autoimmune challenges. This includes people who may be sensitive to loud noises, past emotional traumas, current stress stimulations and stressors, infections, heavy metal exposure, chemical exposure, pollutants, toxins, and other outside stiumulus.
Heart rate variability (HRV) is one of the ways you can measure your vagal tone
Heart rate variability (HRV) is one of the ways you can measure your vagal tone and can be a great indicator of overall health and ability to heal. We use it frequently to help some of our more complex neck patients who are being treated for disabling conditions. It helps them be able to monitor the effects of various stressors on their life and how their vagal tone is improving throughout the Prolotherapy and cervical curve correction treatment series. Our team also uses HRV monitors to check in on their own health. It is amazing what you can learn about yourself just by taking a good, honest look at your HRV and what causes it to increase or decrease.
In the image below a finger sensor heart rate variable device is shown.
When you tell a lie, even if you might think it is necessary, your HRV will go down. There are other things that people are culturally accustomed to but are not doing their HRV any favors, such as chewing gum. People chew gum because they like it, and many people would tell you that they think that it makes them feel good. But physiologically-speaking, we can tell you definitively that chewing gum is stressful. Check your HRV when you are chewing gum and you can see it decrease.1,2 Chewing gum, therefore, decreases vagal tone.3,4 It takes a lot of work from your masseter muscles and other muscles of chewing in your face which stimulates the trigeminal nerve which ultimately stimulates your sympathetic nervous system putting your body in a state of stress!
On the other hand, spend time playing with a kitten or puppy and you will see your HRV go up. Smile more and your HRV will go up. Complain more and it goes down. It is that simple!
Here are some things that you can do to strengthen your vagus nerve:
- Alternate-nostril breathing
- Apply cold compresses to your face and the back of your neck
- Be quiet
- Breathe deeply and slowly
- Compliment others
- Connect with nature
- Diaphragmatic breathing, the slower the better
- Eat a whole-foods diet
- Exercise (within your ability/within your physician’s guidelines if you are being treated for upper cervical instability)
- Expose your skin to sunlight
- Have an attitude of gratitude
- Hum (such as a rhythmic Om)
- Laugh and giggle often
- Listen to calming instrumental music versus amped-up, heavy music
- Listen to music with uplifting, happy, grateful lyrics versus complaining, bitter, spiteful lyrics
- Sing (make a joyful noise!)
- Nostril breathing (versus mouth breathing)
- Pray for your own healing and for others (including those who you may see as “enemies” or ones who have hurt you)
- Regularly move your body
- Say “thank you”
- Smile as much as possible
- Take probiotics or eat probiotic foods
- Visit with people who lift your spirit versus make you feel crummy
Being fit versus sedentary effects on vagal tone
We know there are immeasurable health benefits to regular exercise and avoiding a sedentary lifestyle. It is no surprise, then, that there is a positive correlation between exercise and vagal tone! Consider one study where rats were subjected to chronic endurance training for 12 weeks to see the effect on the vagus nerves.5 After 12 weeks of training:
- The exercised rats showed a significant increase in the diameter of the axon and of the myelin sheath of the vagus nerve fibers.
- The diameter of the unmyelinated vagal fibers increased significantly in the exercised rats.
- Lastly, in the exercised rats, there was an increase in the number of microtubules and neurofilaments per unit area in the myelinated fibers (shows the transporting of substances within the axon would increase).
With positive changes in the vagus nerves, one would expect an increase in vagus nerve function, beginning a virtuous cycle of improving numerous aspects of your health!
Vagus nerve stimulators
In some cases, our patients are recommended to use a vagus nerve stimulator between Prolotherapy treatments.
Vagus nerve stimulators are known to stimulate the nucleus tractus solitarius and affects its projections to the forebrain, limbic, and brainstem sites, including spinal trigeminal nucleus, parabrachial area, dorsal raphe nucleus (DRN), periaqueductal gray, thalamus, amygdala, insula, nucleus accumbens, hypothalamus and locus coeruleus (LC). One functional MRI study showed with left ear vagal stimulation decreases in blood flow (activity) in the following areas: limbic and temporal brain areas, including bilateral amygdala, parahippocampal gyrus, precuneus region, temporal gyrus, posterior cingulate cortex, paracentral lobe, superior frontal gyrus, and left hippocampus.6 It also increases in Blood Flow (Activity) in insula and precentral gyrus on both sides and in the right thalamus and right anterior cingulate cortex.
A summary of other fMRI studies7,8 notes that vagus nerve stimulation causes a decrease in activity in the areas of the brain that produces physiological responses to stress and panic, including the locus coeruleus nuclei in the pons (the principle site of brain norepinephrine). The locus coeruleus projections are far and wide. They include the spinal cord, brainstem, cerebellum, hypothalamus, thalamic relay nuclei, amygdala, and cerebral cortex. The norepinephrine from the locus colureus (LC) has excitatory effects on most of the brain, causing arousal and priming the brain’s neurons to be activated by stimuli. For some patients, vagus nerve stimulation may have positive effects on the nucleus of the solitary tract (NTS) and locus colureus, thus, affecting all of the places these neurons go to including other parts of the brainstem, cerebellum, spinal cord and, of course, the brain!
Ear Bud/Clip Vagus Nerve Stimulation (EB-VNS) Clinical Effects:
- Improved Quality of Life (QOL).
- Decreased body pain.
- Increased sleep quality.
- Improved mood.
- Lessening of severe depression and anxiety.
- Decline in inflammation.
- Improvement in rheumatoid arthritis bloodwork.
- Resolution of acute migraine and cluster headaches.
- Decrease in epileptic seizures.
- Stroke rehabilitation improved.
- Weight loss.
- Improved heart function (pumping).
- Decreased tinnitus.
- Improvement in lung function.
- Angina lessened.
- Heart disease patients have increased exercise tolerance.
- Decreased baseline heart rate and blood pressure.
- Atrial fibrillation episodes decrease.
- Hamada Y, Yanoaka T. The effects of gum chewing while walking on physical and physiological functions. J Phys Ther Sci. 2018;30:625-629.
- Ekuni D, Tomofuji. Gum chewing modulates heart rate variability under noise stress. Acta Odonotol Scand. 2012;70(6):491-496.
- Shiba Y, Nitta E. Evaluation of mastication-induced change in sympatho-vagal balance through spectral analysis of heart rate variability. J Oral Rehabil. 2002;29(10):956-60.
- Hasegawa Y, Sakagami J. Circulatory response and autonomic nervous activity during gum chewing. Eur J Oral Sci. 2009;117(4):470-473.
- Pianca E, Neto WK. Endurance training induces structural and morphoquantitative changes in rat vagus nerve. Rev Bras Med Esporte. 2015;21(5)> doi: http://dx.doi.org/10.1590/1517-869220152105143990.
- Kraus T, Hosl K. BOLD MRI deactivation of limbic and temporal brain structures and mood enhancing effect of transcutaneous vagus nerve stimulation. J Neural Transm (Vienna). 2007;114:1485-1493.
- Mohsin F. the anatomical basis for transcutaneous auricular vagus nerve stimulation. J Anatomy. 2019. Doi: 10.1111/joa.13122.
- XZhang Y, Liu J. Transcutaneous auricular vagus nerve stimulation at 1 Hz modulates locus coeruleus activity and resting state functional connectivity in patients with migraine: An fMRI study. Neuroimage Clin. 2019;24:101971. Doi: 10.1016/j.nicl.2017.101971