The Vagus Nerve and Allergies
Recent research has highlighted the link between the vagus nerve and allergies, due to its modulating effects on the immune system and anti-inflammatory potential. So, what does this mean for allergy sufferers?
What is the vagus nerve?
The vagus nerve is the longest nerve in your body. It connects your brain to many important organs throughout the body, including the gut (intestines, stomach), heart and lungs. In fact, the word “vagus” means “wanderer” in Latin, which exactly represents how the nerve wanders all over the body and reaches various organs.
The vagus nerve is also a central part of your parasympathetic “rest and digest” nervous system. It affects your breathing, digestive function, and heart rate, all of which can have a huge impact on your mental health.
It is an information superhighway that allows the brain to ‘see’ what’s going on inside our own body. If you notice you are hungry, your heart is beating fast, you are short of breath, it’s because of information that has traveled up the vagus nerve.
Studies have even shown that vagal tone is passed on from mother to child. Mothers who are depressed, anxious, and angry during their pregnancy have lower vagal activity. And once they give birth to their child, the new-born also has low vagal activity and low dopamine and serotonin levels. Low vagal tone is associated with poor emotional and attentional regulation in children and has been conceptualized as a marker of sensitivity to stress in child adolescents and adults.
What you need to be aware of is the “tone” of your vagus nerve. Vagal tone is an internal biological process that represents the activity of the vagus nerve. Increasing your vagal tone activates the parasympathetic nervous system, and having higher vagal tone means that your body can relax faster after stress.
In 2010, researchers discovered a positive feedback loop between high vagal tone, positive emotions, and good physical health. In other words, the more you increase your vagal tone, the more your physical and mental health will improve!
Your vagal tone can be measured by tracking certain biological processes such as your heart rate, your breathing rate, and your heart rate variability (HRV). When your heart rate variability (HRV) is high, your vagal tone is also high.
Signs and symptoms of low vagal tone
- Anxiety, depression and mood disorders
- Headaches, migraines
- Inability to relax while eating, inability to feel full
- Low stomach acid and secretion
- Low or slow bile acid production making it harder to digest fats and clear toxins
- Constipation, SIBO, IBS, poor absorption of nutrients
- Food sensitivities
- Insomnia, interrupted sleep,
- Poor breathing patterns
- Loneliness
- Difficulty meditating
- Chronic fatigue
- High blood pressure, high resting heart rate
- Poor blood flow to kidneys
- Poor glucose control
- Frequent urination
- Inability to concentrate
- Chronic inflammation
If your vagal tone is low you can help improve it by stimulating your vagus nerve. People who have a higher vagal tone have healthier hearts, digest their food better, reduce their inflammation, create stronger social bonds, and have an easier ability to feel calm and peaceful.
The vagus nerve and allergies
There is new research investigating the link between the vagus nerve and allergies, by looking at how vagus nerve stimulation improves food allergies by reducing mast cell degranulation. The data suggests that the vagus nerve not only modulates the innate immune system but also the adaptive immune system. It also can prevent inflammatory cytokines involved in mast cell disorders from being synthesized/released, especially in the stomach. Vagus stimulation has also been shown to reduce histamine-induced itching.
A neuroscientist proposes that an infection of the vagus nerve triggers a difficult to detect immune system response which produces the fatigue in chronic fatigue. Histamine/mast cell activation can be secondary to an infection/virus. Vagus stimulation restores the body’s natural immune function rather than disabling it. The body can then respond normally to infection rather than being more prone to it.
The vagus nerve has emerged as an important modulator of the intestinal immune system. Its anti-inflammatory properties and neuro-immune interactions with the intestine may help with food allergies. The vagus nerve explains how the brain talks to the stomach and heart and why it is important to control the messages back and forth, to benefit from the link between the vagus nerve and allergies.
Acetylcholine is the vagus’ nerves neurotransmitter, it’s how it communicates with the rest of the body. AlthoughiInterestingly, some stomach and anxiety medication can actually inhibit it.
Ways to strengthen your vagal tone and stimulate the vagus nerve.
During a Positive Association Technique (PAT) treatment, we optimise this link between the vagus nerve and allergies. We use a chiropractic tool called an “acustim” to stimulate acupressure points, nerve bundles and the vagus nerve that lie along either side of the spine. This stimulation, along with exposure to the trigger substance (by holding a sample vial), aims to re-train the body to no longer have the negative reaction to the substance, and minimise symptoms.
There are a few other ways to tone your vagus nerve as well –
Deep and slow breathing
Deep and slow breathing has been shown to reduce anxiety and increase the parasympathetic system by activating the vagus nerve.
Breathe in deeply from your diaphragm. When you do this, your stomach should expand outward. The deep inhalation stretches the fibers around the lungs – that sensory input travels up the vagus nerve to the brain triggering exhalation which activates the parasympathetic nervous system, and calms you down.
Your exhale should be long and slow. This is key to stimulating the vagus nerve and reaching a state of relaxation.
It’s also worth noting, this is why we instruct our clients to take deep, slow breathes during a PAT treatment.
Acupuncture of the ear
Traditional acupuncture points to the ear stimulates the vagus nerve. There’s also products that stimulates the middle of the ear where the vagus nerve branches out with
electrical signals reduces anxiety. Another company has developed a wire that can wrap around the vagus nerve in the neck reducing the frequency of seizures in patients with epilepsy.
Cold exposure
Acute cold exposure has been shown to activate the vagus nerve and activate cholinergic neurons through vagus nerve pathways. Researchers have also found that exposing yourself to cold on a regular basis can lower your sympathetic “fight or flight” response and increase parasympathetic activity through the vagus nerve.
● Take cold showers and go outside in cold temperatures with minimal clothing.
● Try finishing your next shower with at least 30 seconds of cold water and see how you
feel. Then work your way up to longer periods of time.
● You can also ease yourself into it by simply sticking your face in ice-cold water, this is
especially beneficial after exercise.
Meditation
Meditation can stimulate the vagus nerve and increase vagal tone. Research shows that meditation increases vagal tone and positive emotions and promotes feelings of goodwill towards yourself. Take a moment each day to be grateful for 5 things in your life and think of loving, kind, compassionate and forgiving thoughts towards others and yourself.
Sound therapy, singing, humming, chanting and gargling
The ear and hearing have a significant effect on the rest of the body due to its closeness to the vagus nerve. The ear is a parasympathetic regulatory organ that uses innervation of the vagus nerve to affect the whole body. Auditory stimulation of the vagus nerve can lead to reduced activity of the limbic system.
● Solfeggio frequencies – specific tones of sound that date back to ancient history which can help in bringing the body back into balance and aid healing, i.e. chanting done by the Gregorian monks.
● Listening to tuning forks, Tibetan singing bowls, crystal singing bowls.
● Listening to the sound of running water, a water fountain, waterfall, river, and ocean waves
● The vagus nerve is connected to your vocal cords and the muscles at the back of your throat. Singing, humming, chanting and gargling can activate these muscles and stimulate your vagus nerve.
Probiotics
Gut bacteria can have a beneficial effect on mood and anxiety, partly by affecting the vagus nerve. Researchers have found that certain gut bacteria can improve brain function by affecting the vagus nerve. Animals were given the probiotic Lactobacillus Rhamnosus, in which researchers found positive changes to the GABA receptors in their brain, a reduction in stress hormones, and less depression and anxiety-like behavior. The researchers also concluded that these beneficial changes between the gut and the brain were facilitated by the vagus nerve. When the vagus nerve was removed in other mice, the addition of Lactobacillus Rhamnosus to their digestive systems failed to reduce anxiety, stress, and improve mood.
Another study found that the probiotic Bifidobacterium Longum normalized anxiety-like behavior in mice by acting through the vagus nerve.
A high vagal tone improves the function of the digestive system by improving production of stomach acid and digestive enzymes.
Omega-3 Fatty Acids
Omega-3 fatty acids are essential fats that your body cannot produce itself. They are found primarily in fish and are necessary for the normal electrical functioning of your brain and nervous system. Researchers have also discovered that omega-3 fatty acids increase vagal tone and vagal activity by reducing the heart rate and increasing heart rate variability, which means they likely stimulate the vagus nerve. High fish consumption is also associated with “enhanced vagal activity and parasympathetic predominance”.
Massage
Massages can stimulate the vagus nerve, and increase vagal activity and vagal tone. The vagus nerve can also be stimulated by massaging several specific areas of the body. Foot massages (reflexology) have been shown to increase vagal modulation and heart rate variability, and decrease the “fight or flight” sympathetic response.
How to use Myofascial balls to stimulate the vagus nerve and improve gut motility –
Lie on your back with myofascial balls on the back of the neck – this area is the origin of the vagus nerve from where it travels through the body to the gut (sometimes this will start the stomach to gurgle and you know you are in the right place). Lie there for 5 minutes and practice breathing long slow breaths to further relax your parasympathetic nervous system.
Exercise
Exercise increases your brain’s growth hormone, supports your brain’s mitochondria, and helps reverse cognitive decline, and now researchers have found that it has been shown to stimulate the vagus nerve.
Socialising and laughing
Reflecting on positive social connections improves vagal tone and increases positive emotions. Laughter has been shown to increase heart-rate variability and improve mood. Vagus nerve stimulation often leads to laughter as a side effect, suggesting that they are connected and influence one another.
Vagus nerve stimulation needs to be practiced regularly to be most effective. By stimulating the vagus nerve, you can send a message to your body that it’s time to relax and de-stress, which leads to long term improvements in mood, wellbeing and resilience.
Written by Jenny
Jenny Bates (Adv Dip Naturopathy, Dip Nutrition) has been a Naturopath performing PAT since 2004. Over that time, she has worked with countless clients in both our Sydney and Auckland clinics, and now assists with the training and mentoring of PAT practitioners all over Australia and NZ.
Please note that this blog post contains general information only. Always consult your health care professional regarding any medical condition.
