I think it’s safe to say that most people, and even most healthcare practitioners, don’t understand how important the vagus nerve is to our overall health, let alone our thyroid health. As you’re about to learn by reading this post, if you have vagus nerve dysfunction, this not only can directly affect your thyroid health, but it can also affect your gut and immune health, and thus be a factor in autoimmune thyroid conditions such as Graves’ disease and Hashimoto’s.
Although I will discuss some of the basics of vagus nerve function in this blog post, I want to let you know that on Monday June 15th there is an upcoming Vagus Nerve online summit you might be interested in attending. When you register you’ll also receive Dr. Eva Detko’s 25-page eguide entitled “4-Week Program to Strengthen Your Vagus Nerve and Boost Your Immune System”.
Click Here  to register for the free Vagus Nerve Summit
In order to understand the importance of the vagus nerve I think it makes sense to briefly discuss it’s role. There are twelve cranial nerves, and the vagus nerve is the longest, and most complex of these. The vagus nerve is part of the autonomic nervous system. The two components of the autonomic nervous system are the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The SNS is involved in the “fight or flight” response, while the PNS is known as the “rest and digest” system. The vagus nerve is part of the PNS.
How Does The Vagus Nerve Affect Thyroid Function?
As for the relationship between the vagus nerve and thyroid health, the thyroid gland is located anteriorly in the lower part of the neck, and the autonomic nervous system primarily innervates the thyroid. Both the SNS and PNS supply the thyroid gland, and the vagus nerve is the main nerve from the PNS that supplies the thyroid gland. However, these nerves don’t control the production or secretion of thyroid hormone, but mostly influence the vasculature of the thyroid gland (1) .
How Does The Vagus Nerve Affect The Immune System?
As for how the vagus nerve affects the immune system, there are a few different ways. First of all, it innervates the immune organs, including the spleen, thymus, and the gut. There is actually a good amount of research on the gut-brain axis, and the vagus nerve plays an important role in this communication. Low vagal tone has been associated with numerous conditions involving the gut, including irritable bowel syndrome, inflammatory bowel disease, and SIBO (2) .
Keep in mind that the vagus nerve plays a role in stomach acid secretion, and so if you have low stomach acid, vagus nerve dysfunction can be one potential cause. And low stomach acid alone can cause a lot of problems, including intestinal dysbiosis/small intestinal bacterial overgrowth. When I suspect low stomach acid in my patients there are times when I recommend for them to take betaine HCL, but of course the goal is to address the cause of the problem.
How Chronic Stress Affects The Vagus Nerve
So now that you know some of the consequences of dysfunction of the vagus nerve, it probably would be a good idea to discuss how chronic stress can have a negative effect on vagus nerve function. Without question chronic stress is the main factor that can have a negative effect on vagus nerve function. This is one of the reasons why chronic stress is pro-inflammatory, as the vagus nerve is also involved in something called the cholinergic anti-inflammatory pathway (3) .
It’s also important to mention that stress stimulates the sympathetic nervous system while inhibiting the parasympathetic nervous system. Stress causes a release of corticotrophin-releasing factor, and this can cause an increase in intestinal permeability (a leaky gut) and intestinal dysbiosis (4) . So hopefully you understand how chronic stress can lead to inflammation and affect the health of the gut.
I’ve mentioned the Triad of Autoimmunity  in the past, as this involves three factors that are necessary for an autoimmune condition to develop. These three factors are 1) a genetic predisposition, 2) an environmental trigger, and 3) a leaky gut. So vagus nerve dysfunction can set the stage for autoimmunity not just by causing an inflammatory environment, but by causing a leaky gut and gut dysbiosis.
How To Improve The Health of Your Vagus Nerve
One of the best ways to improve the health of the vagus nerve is by incorporating mind body medicine. This includes techniques such as meditation, yoga, qigong, biofeedback, etc. Dr. Datis Kharrazian is the author of the amazing book “Why Isn’t My Brain Working”, and he wrote a blog post that discusses four vagus exercises  you can incorporate:
1. Gargle (2 minutes of vigorous gargling). Gargling with water a few times per day can activate the vagus nerve. Dr. Kharrazian recommends to drink several large glasses of water per day and to gargle each sip until you finish the glass of water.
2. Stimulate your gag reflex. Dr. Kharrazian mentions that he has his patients purchase a box of tongue blades so they can stimulate their gag reflex throughout the day. You would just lay the tongue blade on the back of your tongue and push down to activate a gag reflex.
3. Sing loud in the shower. Dr. Kharrazian recommends to sing as loudly as you can when you are in the car or at home. I usually do this while taking a cold shower, which also can activate the vagus nerve!
4. Coffee enemas. Although many people use coffee enemas as a form of detoxification, I was surprised to learn that coffee enemas can help to activate the vagus nerve.
One thing that isn’t on this list is to see a doctor of chiropractic. Of course I’m going to be biased since I’m a chiropractor, but while many people perceive chiropractors as being neck and back pain doctors, the truth is that they can greatly help to improve the health of people’s nervous systems. In fact, one study I came across showed that spinal adjustments of the cervical spine can affect the parasympathetic nervous system (5) . On the other hand, the study also mentioned that spinal adjustments of the thoracic spine resulted in a sympathetic response. Acupuncture is also something to consider.
While I do recommend nutritional supplements and herbs to my patients, you might have noticed that nothing I just mentioned involves taking supplements! So even someone who is on a budget can do things to improve the function of their vagus nerve.
Vagus Nerve Activation Schedule
Dr. Eva Detko has put together a guide, which includes a weekly schedule consisting of things you can do to activate your vagus nerve. And so if you’re looking to start a daily routine that only takes a few minutes today Click Here . Upon clicking on this link you will be taken to another page where you will be asked to enter your email address, and besides receiving the free guide where she lists her weekly schedule, you will also be registered for the upcoming vagus nerve summit I mentioned earlier.
How Heart Rate Variability Affects The Vagus Nerve
Dr. Eva mentions heart rate variability in her guide too, but I also wanted to bring this up here, as I’ve written about heart rate variability in the past. In the article I wrote I mentioned how I use a device by the company HeartMath to help improve heart rate variability, which is a way of measuring vagal nerve tone. An elevated heart rate isn’t a good thing, but we do want a high heart rate variability.
So hopefully you have a better appreciation of the importance of the vagus nerve, and how chronic stress can have a negative effect on the gut and immune system. Chronic stress is a big factor in many people, especially in 2020 with everything going on. And while in past articles and blog posts I’ve mentioned the importance of blocking out time for stress management, and it’s something I also encourage my patients to do, for many people it would also be a good idea to incorporate one or more of the vagus nerve exercises I listed earlier.