What Is Vagal Tone and How to Improve Yours

What Is Vagal Tone and How to Improve Yours

Improving Vagal Tone for Better Gut, Brain, and Emotional Health

The function of the vagus nerve, known as vagal tone, may offer insight into our physical, neurological, and emotional health. Because the vagus nerve is so important for the gut-brain connection and other connections within the body, if the vagus nerve is not working correctly, there might be a greater risk of conditions including gastrointestinal issues, heart disease, depression, and anxiety. 

What Is Vagal Tone and How to Improve Yours - The%20Importance%20of%20the%20Vagus%20Nerve Landscape L

There are claims that all kinds of things improve vagal tone, from gargling saltwater and tapping on your chest, to electrical stimulation of the vagus nerve. This article will explore the research about what interventions actually help improve vagal tone and how improved vagal tone may help improve certain health conditions. 

In general, lifestyle practices that are good for your gut and good for your brain (like diet, exercise, and deep breathing) can improve your vagal tone. More specific vagus nerve-targeted practices like tapping or gargling don’t seem to be effective or necessary for most people. 

The exception is electrical vagus nerve stimulation (VNS), which has been shown in clinical trials to help improve vagal tone and symptoms of gastrointestinal, cardiovascular, autoimmune, and mental health conditions. This is a promising therapy, but not a starting point. Let’s dive in and learn more. 

Key Takeaways

  • General healthy habits help improve vagal tone, such as exercise, mindfulness, and slow breathing techniques.
  • More research is needed to prove that other methods such as gargling, laughing, and vagus nerve tapping are effective.
  • Improving vagal tone has been associated with improvement in many gastrointestinal illnesses, mental health, anxiety, cardiovascular function, and autoimmune conditions.
  • Vagal tone is a measurement of how well the vagus nerve is working.
  • The best measurement of vagal tone that we have currently is heart rate variability (HRV).
  • Low vagal tone has been associated with several gastrointestinal and neurological conditions such as IBS, colitis, heart disease, depression, epilepsy, and Parkinson’s disease.

What Is the Vagus Nerve?

The vagus nerve travels from your brain stem into multiple areas of your body such as your heart, gut, lungs, and tongue. It helps regulate the automatic systems of our body such as breathing, heart rate, blood pressure, hormones, and digestion. It also regulates our fight, flight, or freeze reactions, which affect our anxiety levels and ability to handle emotional and physical stressors. 

Measuring vagal tone and the functioning of the vagus nerve is not straightforward, and the concept of improving vagal tone is relatively new in functional and conventional medicine. Let’s take a look at what we do know about improving vagal tone and how you can support your vagus nerve at home.

What Is Vagal Tone?

Vagal tone: side view of a brain illustration

Vagal tone tells us how well the vagus nerve is functioning, and it is measured indirectly by heart rate variability (HRV). Heart rate variability is a measurement of the amount of time between heartbeats, which is really an indicator of vagal activity of the heart. We actually want to have variability, not to be consistent [1 Trusted SourcePubMedGo to source]. The more variable the time is in between heartbeats, the better your vagal tone. Higher HRV means better vagal tone, and lower HRV means poorer vagal tone [2 Trusted SourcePubMedGo to source, 3 Trusted SourcePubMedGo to source, 4 Trusted SourcePubMedGo to source].

On a side note, you may have heard of HRV in reference to fitness recovery. HRV can indicate how well your body recovers and returns to the rest and digest stage after exercise stress [1 Trusted SourcePubMedGo to source].

It’s important to remember though that there are no baselines for what is considered a low or high vagal tone. Meaning, we can’t say that a high HRV for men ages 30-40 should be X [5 Trusted SourcePubMedGo to source]. Your HRV baseline is individual, so a high HRV for you could be 42, while high for someone else is 66.

Vagal tone’s relationship to the heart is why you may have also heard that cardiac vagal tone is a good indicator of how well our heart and parasympathetic nervous system are working. HRV is a metric for predicting cardiac vagal tone. 

Low vagal tone is associated with:

If you are looking to get a sense of the health of your vagus nerve, there are a few devices that track HRV for you. Two good examples are the Oura Ring and the Whoop Band. I use an Oura Ring myself to track my sleep. Both of these devices calculate your HRV during sleep and help you find your baseline so that you know if your vagal tone is improving over time. These are not essential, but if you like more in-depth data, these can be a great option. 

The real question is, though: While low vagal tone is associated with many health conditions, will vagus nerve stimulation (VNS) improve vagal tone and symptoms in any of these conditions? 

Vagal Nerve Stimulation Improves Vagal Tone

Electrical vagal nerve stimulation is the most studied method when it comes to improving vagal tone, and it has been shown to be effective and beneficial. 

Electrical Vagal Nerve Stimulation

Vagal tone: electrodes and electrical stimulation device

The FDA has approved electrical vagal nerve stimulation for epilepsy and treatment-resistant depression, and it is also currently being studied for use in treatment for migraines, obesity, IBD, Parkinson’s disease, Alzheimer’s disease, and more [15 Trusted SourcePubMedGo to source, 16 Trusted SourcePubMedGo to source]. There are two types of electrical vagal nerve stimulation: invasive and non-invasive.

Invasive electrical VNS is when a device is surgically implanted under the skin on the chest to stimulate the vagus nerve. This is most often used for the treatment of epilepsy and treatment-resistant depression, but it is being studied for use in other conditions. 

In fact, in a study of patients with Crohn’s disease, invasive VNS reduced GI tract inflammation and IBD symptoms after 4-6 months of use [7 Trusted SourcePubMedGo to source].

Invasive VNS does come with a low level of risk such as the risk of infection at the surgical site, cough, difficulty breathing, or vocal cord paralysis [16 Trusted SourcePubMedGo to source]. Fortunately, non-invasive VNS is also very effective, without these risks. 

There are two forms of non-invasive electrical VNS, taVNS (transcutaneous auricular vagus nerve stimulation) and ctVNS (cervical transcutaneous vagus nerve stimulation). In taVNS, an electrode is placed on the ear to stimulate the vagus nerve, and in ctVNS, the electrode is placed on the neck [17 Trusted SourcePubMedGo to source].

Benefits of taVNS and ctVNS: [18 Trusted SourcePubMedGo to source, 19 Trusted SourcePubMedGo to source, 20 Trusted SourcePubMedGo to source, 21 Trusted SourcePubMedGo to source]

  • Seizure frequency was decreased by 20-40% in patients with epilepsy.
  • May reduce circulating levels of inflammatory markers in the body. 
  • Gastrointestinal pain, pelvic pain, and migraines were significantly improved.
  • Depression and anxiety scores improved.
  • Symptoms of indigestion and IBD were improved, and inflammation was decreased in patients with gastrointestinal disease. 

Most people do not have access to electrical VNS, which should be done only with a medical professional, but there are other non-invasive ways to increase vagal tone. Let’s look at a few that have the most efficacy.

Non-Invasive Ways to Improve Vagal Tone

Working on the vagus nerve has become more popular, with everything from meditating, tapping the chest, and laughing to cold water therapy, diet, and exercise being used for vagal nerve stimulation. While there are many randomized clinical trials on electrical VNS, we do not have as many studies to look at for these other types of vagal nerve techniques. This does not mean that they do not work or are not providing benefits to people, but rather that we need more studies. 

In many studies, the measurement of improved vagal tone is heart rate variability (HRV), but in others, a self-rated perceived reduction in symptoms was the measurement of improved vagal tone. 

The difficulty with testing for improved vagal tone is that currently there really is no way to test the vagus nerve, but HRV is the closest measurement we have of it right now, and all that is testing is the functioning of the heart. However, because the vagus nerve travels to so many other areas of the body, many people infer that improved digestion or less anxiety shows improved vagal tone. That may be true, but we just don’t have the research yet to prove that this is true.

The bottom line is that most of these are safe and non-invasive, generally good for your health and well-being, and if you see improvements trying them, then they work for you. 

Let’s look at some of the most popular interventions, starting with the easiest to do at home, and the supporting research so you can see if you want to try any of them. 

Exercise

There are many smaller studies showing that exercise can improve your vagal tone, and this is probably one of the easiest interventions to do at home [8 Trusted SourcePubMedGo to source]. There are also numerous health benefits associated with exercise beyond increasing vagal tone. 

High-intensity exercise was shown to improve vagal tone better than moderate-intensity exercise in people with chronic heart failure [22 Trusted SourcePubMedGo to source]. However, even light exercise like walking has been shown to improve HRV [8 Trusted SourcePubMedGo to source].

In general, I find that clients who use an HRV tracker do see improvements in HRV when adding exercise into their life. It is important to note that more exercise does not necessarily mean better. Over-exercising, with too much high-intensity exercise without enough recovery time, can lower HRV.

Breathing and Meditation

Vagal tone: man breathing deeply

The vagus nerve helps to control our breathing, and research shows that we can improve vagal tone by practicing certain types of breathing.

The easiest form of vagus nerve breathing is to make your exhalation longer than your inhalation. When we breathe out, our heart rate decreases and we stimulate the vagus nerve. Just as you may notice that when you are anxious your breathing may become short and fast, indicating sympathetic nervous system activation, so slow breathing helps increase parasympathetic activity [8 Trusted SourcePubMedGo to source].

In one study, slow breathing, at around 5.5 beats per minute, showed the most improved HRV and vagal tone and increased levels of relaxation. In this study, the out-breath and in-breath were equal, at five seconds in and five seconds out [23 Trusted SourcePubMedGo to source]. However, many other studies looking at meditative practices and variations in breathing show most forms of slower breathing improve HRV, decrease stress and anxiety, and even improve chronic pain and gastrointestinal symptoms [24 Trusted SourcePubMedGo to source, 25 Trusted SourcePubMedGo to source, 26 Trusted SourcePubMedGo to source].

There are other types of possible ways to stimulate the vagus nerve through singing, chanting, and humming. However, all of these practices slow the breathing in some way, which may be why people see improvements in HRV and feelings of calm and decreased stress and anxiety [27 Trusted SourcePubMedGo to source]. Adding in 10-20 minutes of slow and mindful breathing each day can be a great way to improve your vagal tone.

Diet and Probiotics

There are some dietary interventions that may help improve vagal tone. Anything that is good for the gut and brain is good for the vagus nerve. In general, anything that increases inflammation and decreases gut health will tax the parasympathetic nervous system via the gut-brain axis (the vagus nerve).

A generally anti-inflammatory and nutrient-dense diet, such as a Paleo diet that removes inflammatory foods such as grains, dairy, and legumes, may be helpful.

Some studies also show that supplementation with fish oil significantly increased vagal tone and resulted in higher heart rate variability [28 Trusted SourcePubMedGo to source]. Further, one study suggests that maintaining adequate sodium levels (which will vary from person to person as some are more sensitive to sodium than others,) increases HRV. Generally, a low sodium diet decreased HRV [29 Trusted SourcePubMedGo to source].

Probiotics can also be a good way to support the vagus nerve as they can help heal the gut and strengthen the gut-brain axis. We need research to show that probiotics can directly improve HRV/vagal tone, but we do have a large body of research supporting using probiotics for improved gut health. And again, what is good for the gut and brain is good for the vagus nerve.

Cold Water

Woman about to go into a frozen lake

Have you taken the cold water bath plunge? Short cold water baths, of about two minutes, have become popular in athletic communities as being great for muscle recovery and improving HRV. And, research does back this up, although exactly how cold the water needs to be, how long you need to stay in the water, and how often you need to do it is not yet agreed upon [8 Trusted SourcePubMedGo to source].

Coldwater immersion has been shown to reduce heart rate, improve HRV, and increase parasympathetic nervous system activity after exercise [8 Trusted SourcePubMedGo to source].

If you want to test out cold water therapy, start off with taking the last 10-20 seconds of your shower on the coldest water setting you can handle. If you have poor vagal tone, jumping into an ice bath may not be something your body can handle yet, so test the waters with a cold shower first. 

Tapping, Gargling, and Laughing

Woman laughing hysterically

Vagus nerve tapping, where you lightly tap on the chest while holding your breath to stimulate the vagus nerve, has become increasingly popular. Many people anecdotally report improved mood and decreased stress and anxiety. However, there are no studies published about “vagus nerve tapping.” Again, this does not mean it is not helping people who use it, we just don’t have the research to show it improves vagal tone and increases HRV.

Vagus nerve tapping should not be confused with EFT (Emotional Freedom Technique) which is a form of tapping used in psychotherapeutic settings in addition to cognitive behavior therapy. This form of tapping taps on acupressure points in order to help decrease levels of anxiety and improve emotional regulation. However, the points you tap during an EFT routine are different from those that would be associated with the vagus nerve.

Because the vagus nerve goes to the throat and affects swallowing as well as the dilation of the throat, some people suggest periodically gargling with salt water or gagging can improve vagal tone. Some believe laughing may stimulate the vagus nerve because the vagus nerve also goes to our diaphragm and we laugh with our belly. But good research does not exist to support these as interventions for improving vagal tone.

Vagus Nerve Massage

Vagus nerve massage essentially uses light to moderate pressure in areas of the body near the vagus nerve, such as in the neck/shoulder area near the base of the skull or on the side of the neck near the carotid artery (in carotid sinus massage,) to increase vagal tone and slow heart rate [30 Trusted SourcePubMedGo to source].

Both forms of massage have been shown to increase HRV and decrease subjective stress. Carotid sinus massage (CNS) is used in cardiology emergency settings to slow a rapid heart rate or improve abnormal heart rhythm as it stimulates a receptor in the carotid artery to raise vagal tone. CNS does come with risks, especially for people with heart disease. It should not be used in people with diseased carotid arteries, stroke, or tachycardia [31 Trusted SourcePubMedGo to source].

Now, let’s take a bit of a closer look at what the vagus nerve is.

The Wandering Vagus Nerve

Why is there so much emphasis on the importance of the vagus nerve for so many different types of health conditions? The vagus nerve is connected in one way or another to many different systems in the body. Here’s a quick chart: 

Body SystemVagus Nerve Relationship
Gut/ Gastrointestinal TractVagus nerve controls the motor (efferent) fibers of the GI tract that create the contractions of muscles to move food through the digestive tract, regulates digestion, and controls the contractions of vomiting [11 Trusted SourcePubMedGo to source, 26 Trusted SourcePubMedGo to source].
HeartThe vagus nerve regulates heart rate and blood pressure. Information is sent from baroreceptors through the vagus nerve, from the heart to the brain [32 Trusted SourcePubMedGo to source].
Lungs, airway, mouth, and throatThe vagus nerve regulates breathing, the diameter of the airway, coughing, and swallowing [32 Trusted SourcePubMedGo to source].
BrainThe gut-brain axis is the vagus nerve, sending signals from the gut to the brain and vice versa [10 Trusted SourcePubMedGo to source, 11 Trusted SourcePubMedGo to source]. Part of this communication includes production of neurotransmitters for emotional health as well as modulation of the parasympathetic and sympathetic nervous systems responsible for feelings of safety, anxiety, and fear.
Endocrine (Hormone)Signals for production of certain hormones are sent through the gut-brain axis, in particular hormones of stress, mood, and hunger [6 Trusted SourcePubMedGo to source, 10 Trusted SourcePubMedGo to source, 27 Trusted SourcePubMedGo to source, 32 Trusted SourcePubMedGo to source].
ImmuneVagus nerve is the modulator of the immune system and immune reactions via the gut-brain axis [26 Trusted SourcePubMedGo to source, 33 Trusted SourcePubMedGo to source].

The vagus nerve is the 10th, and longest, cranial nerve, starting at the brain stem and “wandering” down into the neck, chest, and abdomen. “Vagus” translates from Latin to “wanderer.” It affects the gastrointestinal system, heart, lungs, tongue, and throat [15 Trusted SourcePubMedGo to source, 16 Trusted SourcePubMedGo to source].

The vagus nerve is also the main part of the parasympathetic nervous system (PNS) which is responsible for our body’s “rest and digest” state and regulates automatic body functions such as breathing, heart rate, and digestion [34 Trusted SourcePubMedGo to source].

The PNS works in opposition to the sympathetic nervous system (SNS) and the PNS and SNS together make up our autonomic nervous system (ANS.) The SNS regulates our “fight or flight” state and is needed to respond to stressful situations as well as physical activity [35 Trusted SourcePubMedGo to source].

Because the vagus nerve wanders to so many parts of our body and is part of the autonomic nervous system, it is involved in almost all processes of the body. This makes it particularly important when talking about health because dysfunction of the vagus nerve could be contributing to health disorders. 

Three Steps to Supporting Your Vagus Nerve

Elderly woman walking her dog

Improving vagal tone may be a great way to improve your overall health, particularly if you struggle with GI issues, heart disease, or anxiety. The great news is that simple health interventions can improve your vagal tone. You can decide to track this with a device that measures HRV, or, keep a list of symptoms — emotional and physical — to track and see if they improve as you try an intervention.

It’s best not to try ALL the interventions at once, because then you will not know which ones work. So, let’s simplify your approach.

Most people I work with are already on a journey of eating an anti-inflammatory diet and exercising at least a few days a week. If you are already doing those things, then here is the order in which you could add in some support for your vagus nerve. 

I suggest trying one of these things for two weeks and noting your progress before adding in something else:

  1. In particular, if you have gastrointestinal symptoms, make sure you are taking a good, multi-strain probiotic in addition to following your anti-inflammatory diet. 
  2. Check your exercise. Make sure you are not doing high-intensity training every day and not recovering well. If you are already exercising, adding longer walks in a few days a week can be a happy medium. 
  3. Take 10-20 minutes a day for a breathing practice — either mindfulness meditation, mantra chanting, or just simply slowing your breathing. 

If your symptoms improve, then you know you have found a good way to improve your vagal tone!

If you are still struggling, and want more help to see if vagal tone or something else may be underlying your symptoms, feel free to reach out to us at the clinic. We are happy to help you start to feel and function better. 

The Ruscio Institute has developed a range of high quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.

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I care about answering your questions and sharing my knowledge with you. Leave a comment or connect with me on social media asking any health question you may have and I just might incorporate it into our next listener questions podcast episode just for you!

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