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Many people are yet to understand that the vagus nerve is probably the most important nerve in the human body.
Compared to other nerves, what happens in this vagus doesn’t stay there. The vagus nerve links the brain stem to lungs, heart, and the gut. It also innervates the liver, the gallbladder, spleen, female reproductive organs, ureter, kidneys, tongue, ears, and the neck. It powers our parasympathetic nervous system (this we know), and controls visceral (unconscious) functions of the body from maintenance of heart rate to sweating, digestive functions, and breathing. It also helps with the regulation of blood pressure and blood glucose balance, promotion of general kidney function, release of testosterone and bile, stimulation of saliva secretion, control of taste functions and release of tears. It is also deeply involved in female orgasms and fertility issues in women.
We also know that the vagus nerve has fibers that innervate every internal organ in the body. The vagal nerve connection between the heart, gut, and the brain plays a very vital role in managing and processing our emotions. This explains the strong “gut feeling” that we have towards intense emotional and mental states.
Dysfunction of the vagal nerve can trigger a wide range of problems, such as bradycardia (slow heart rate), obesity, difficulty swallowing, fainting, gastrointestinal disorders, deficiency of vitamin B12, mood disorders, seizures, impaired cough, and chronic inflammation.
On the other hand, stimulation of the vagus nerve improves the following conditions:
Acetylcholine is the major neurotransmitter of the vagus nerve. It stimulates muscle contractions in the parasympathetic nervous system. A neurotransmitter facilitates transmission of signals from point to point. It is released at the end of a nerve fiber. For instance, if our brain fails to communicate with our diaphragm through the release of acetylcholine from the vagus nerve, then breathing would cease automatically.
Certain substances like mercury and botox can interfere with the production of acetylcholine. Clinical research and experience has shown that botox does have the potential to shut down nerve functions, which results in death. Mercury impedes smooth functioning of acetylcholine. When mercury attaches to the protein thiol in the receptors of your heart muscle, it prevents the heart muscle from receiving the vagus nerve electrical impulse for contraction. What follows will be cardiovascular problems. The 3000 tons of mercury that fills our atmosphere can interfere with production of acetylcholine. Vaccines laden with mercury also plays a role in vagus nerve-related autism in children. Some doctors do use galantamine and huperzine (both are natural nootropics) to improve the sensitivity of acetylcholine receptors.
The vagus nerve may also be damaged by alcoholism, diabetes, infections of the upper respiratory organs by viruses, or accidental severing of part of the vagus nerve during surgery. Stress may also cause inflammation of the nerve. Same goes for anxiety and fatigue. Even a bad posture can impact negatively on the vagus.
Diet is also believed to contribute to vagus nerve health. Junk foods that are high in carbs and fats reduces the sensitivity of the vagus nerve. Heavily spiced foods can also cause the nerve to misfire.
The vagus nerve has great healing powers, most of which can be unlocked by improving the vagal tone. The vagal tone can be improved naturally via stimulation with techniques that can be performed at home. Strengthening your vagal tone will help with mood, digestion, and general wellbeing.
The following techniques can help to rekindle the healing powers of your vagus nerve.
The deep-breathing technique
I’ll call it box breathing, or maybe square breathing. This technique is used for slow, deep breaths. It can boost concentration and performance while also acting as potent stress reliever. Box breathing is also known as four-square breathing.
Anyone can benefit from the deep-breathing technique, especially those that are interested in stress relieve or meditation.
The deep-breathing technique may be particularly useful for people with a lung disease such as chronic obstructive pulmonary disease.
Getting started
Before you begin, ensure that you sit upright in a comfortable chair. Your feet should be rested flat on the floor. Make sure your environment is quiet and stress-free so you can focus on your breathing.
Relax your hands on your lap with your palms facing up, and then focus on your posture. You should sit in a straight-up posture. With this, you’ll be able to breathe deeply.
When you are set, start with the following steps:
Exhale slowly: Sitting in an upright posture, exhale slowly through your mouth, making sure that all the oxygen gets out through your mouth. Maintain your focus and be conscious of what you are doing.
Inhale slowly: Breathe in slowly and deeply through your nose. Count to four while breathing in. Feel the air as it fills up your lungs, a particular section at a time, until the lungs are completely filled and the air flows into your abdomen.
Hold your breath: Do this to the count of four.
Exhale once again: Exhale slowly through your mouth to the count of four, flushing out all the air from your abdomen and lungs. Ensure you have a conscious feel as the air leaves your lungs.
Hold your breath again to the slow count of four before repeating the process.
How does the box breathing technique help?
According to a study by the Mayo Clinic 18, there is enough evidence to prove that purposeful deep breathing can calm and regulate functions of the autonomic nervous system.
The autonomic nervous system regulates temperature and other involuntary body functions. It can reduce blood pressure while also providing a sense of calm.
During the moment that you hold your breath, CO2 builds up in your blood. Increase in blood concentration of carbon IV oxide boosts the cardio-inhibitory response of the vagus nerve during exhalation, and then stimulates the parasympathetic system. This allows you to feel calm and relaxed in your body and mind.
Deep breathing reduces stress and serves as a “mood improver.” Hence, it is an exceptional treatment for panic disorder, generalized anxiety disorder, post-traumatic stress disorder, and depression.
It also helps with the treatment of insomnia by calming your nervous system at night just before you sleep off. It is equally helpful with pain management.
Loving kindness meditation
The loving kindness meditation, also known as Metta meditation trains your heart to be loving, kind, humble and forgiving, while also opening your heart to rewire old habits of responding to others. Loving kindness meditation also increases your vagal tone.
Let’s start:
Sit in a quiet place, free of any form of distraction or interruptions. Sit comfortably, in a straight and relaxed position.
Place your palms gently on your thighs and close your eyes.
As you meditate, say these phrases in your mind. Never rush. And be gentle if your mind starts wandering away. Simply repeat the phrases over and over for as long as you like but it shouldn’t be less than four times.
First, direct the meditation towards yourself. It is difficult I agree, but you can do it.
“may I be happy”
“I will be safe”
“I will live with ease”
Channel your focus towards someone that is close to you, a loved one, maybe someone from your past or present, who still keeps in touch, or has passed away, friend, family, spiritual mentor etc. Just imagine that the person is seated right in front of you. Now direct the loving kindness towards them:
“you will be happy”
“you will be safe”
“you will live a life free from pain.”
“you will leave with ease”
After meditating for a few rounds, focus your attention on someone neutral and then offer them meditation.
Also extend the practice to a person you are having difficult times with. You can then extend the practice to include those living in your neighborhood, in your city, and the world at large.
“may everyone live happy.”
“may everyone be safe”
“may everyone be free from pain”
“may everyone live a life of ease”
Consistent practice of loving kindness meditation daily for six weeks has been proven to improve overall health, wellbeing, and vagal tone.
Yoga pose/chanting
Studies have demonstrated a link between yoga and increased vagal tone, as well as general improvement in the parasympathetic activity 19, 20.
A study involving 12 weeks of yoga intervention showed improvements in anxiety and mood compared to walking exercises. According to the study, yoga increases thalamic levels of GABA which are associated with decreased anxiety and improved mood 19.
Yoga also supports overall physical and mental health 21, 22. Yoga practice increases flexibility of both the physical body and the nervous system. Studies have shown that yoga has tremendous benefits including improved vagal tone, recovery from trauma, and stress reduction. With this, you can become skilled at switching between parasympathetic and sympathetic nervous systems with ease and at your own will. The following yoga techniques will boost your development of a healthy vagal tone, relaxation and energization, and as maintenance of balance in your life:
Conscious breathing: Breathing is a quick way to alter the balance between your sympathetic and parasympathetic nervous system. Vagus nerve yoga focuses on diaphragmatic breathing as well as extension of the duration of exhalation. With this, it counterbalances overstimulation of the sympathetic nervous system. Studies have shown that slow, diaphragmatic breathing improves the vagal tone and maintains it at healthy levels 23. Ujjayi pranayama plays a very important role in conscious breathing. It is a form of yogic breathing that allows slight constriction at the back of your throat through engagement of your whisper muscles. Here’s how you can learn the Ujjayi pranayama – exhale out of your mouth. Breath in then exhale again, but this time through your nose. You will notice that the breath sounds louder, often like the ocean waves. Start an even count as you inhale and exhale. For deeper relaxation, increase the length of your exhalation as compared to inhalation. For instance, you may count to four while inhaling and count to 6 or 8 while exhaling. This helps to calm your parasympathetic nervous system.
Half smile: A half smile is a great way to influence your mental state and buildup a peaceful and serene feeling. Because the vagus nerve innervates the muscles of your face, you can increase vagal tone by allowing your facial muscles to relax, and then turning your lips slightly. Doing this engages what Dr. Stephen Porges calls the “social nervous system.” When smiling, imagine your jaw relaxing, and a calm feeling running through your face, your head as a whole, and extending down to your shoulders. Also observe the subtle changes in your emotions and thoughts.
Open up your heart: The vagus nerve can be stimulated gently using yoga postures that opens across your throat and your chest. Sit with your hands on your shoulders. Inhale while expanding across the front of your chest, opening your elbows wide, and lifting your chin. Exhale, while you tuck your chin and contract your elbows in front of your heart. Breathe deeply several times while meditating. More focus should be placed on inhalation. It is uplifting and stimulating. Allow your inner self to expand into your open heart.
Wake and stretch: If you are finding it difficult to wake in the morning or if you feel sluggish and tired in the afternoons, then yoga can give your mind and body a gentle but stimulating touch. You can stand in postures such as the warrior (virabhadrasana) to wake your body and invigorate your mind. Observe as your feet connects to the earth to stay grounded so you can get energized in a balanced manner. Allow your breath to flow in a rhythm so you can be rooted and connected to your body’s sensations.
Release your belly: You can tone the vagus nerve as it passes through your belly. Assume a table position with your knees underneath your hips and your hands underneath your shoulders. If you feel some form of discomfort on your knees, you can fold a blanket and place it underneath. While inhaling, you’re your head gradually while lowering your hips and your belly as you switch to the cow pose. While exhaling, lower your hips and your head and then lift your spine into the cat pose. Time yourself appropriately with your breath. Repeat as many times as possible creating a gentle massage for your spine and belly.
Yoga Nidra: Yoga nidra or restorative yoga calms your nervous system. An instance is the “yogic sleep” or what I’d call meditation-in-relaxation. It is the antidote to our modern and extremely stressful lifestyle. It creates an opportunity to restore your body and mind through accessing your parasympathetic nervous system. To do the yoga nidra, lie on the floor in a relaxing position. Be conscious of your body and breath. Create an allowance, or outlet for your feelings, including any sensation of heaviness, constriction, or tension. Remain still for up to 30 minutes for a relaxing and nourishing experience.
Massage
Massaging some key areas like the carotid sinus (on your neck) helps to stimulate your vagus nerve. Studies have shown that it can reduce seizures 24. Please note, massaging the carotid sinus on your own is not recommended as it can cause fainting or other risks.
One may also activate the vagus nerve through a pressure massage. A pressure massage boosts weight gain in infants by stimulating the gut, an action that is believed to be mediated by vagus nerve activation 25, 26.
Reflexology foot massages also improves vagal activity as well as heart rate variability while reducing blood pressure and heart rate 27.
Cold water splash
A 2008 study 28 involving 10 healthy subjects shows that when the human body adjusts to cold temperatures, the sympathetic nervous system experiences a decline, while activities of the parasympathetic system are stimulated – an action believed to be mediated by the vagus nerve. In the present study, cold temperature was pegged at 50°F (10°C).
Animal studies have shown that sudden exposure to cold (39°F/4°C) increases activation of vagus nerve in rats 29.
Although not many studies have been done on the effect of cold water splash on the vagus nerve, many are proponents of this traditional cooling method.
But come to think of it. We all took cold showers before heating systems were invented. Anecdotally, cold tubs are widely used in Japan, while many Northern nations do ocean dips for special occasions during the early spring or winter.
It takes some time for one to get fully used to cold showers though. Some people believe that it is good to dip one’s face in cold water before starting a cold shower.
Also, it is important that you consult your doctor before doing a cold-water splash. Cold showers are not good for people with a heart disease, or those who have a high risk of it. Why? Because sudden exposure to the cold can constrict the blood vessels, which in turn increases heart rate and blood pressure.
Tai chi
Slow deep breathing and the intent to relax are major components of the Qi Gong and Tai Chi practice. Tai chi activates the parasympathetic nervous system, resulting in the lowering of the acidity in the internal environment. A combination of the soft spiraling and the stretching movements of Qi Gong and Tai chi, together with deep breathing increases oxygen demand. This further activates the alkaline response, aiding internal healing and tissue regeneration.
20 minutes of Qigong and Tai Chi helps to activate the body’s relaxation response. You will have a calm, more centered, relaxed, and alert feeling. Your body returns to a neutral state for improved longevity, happiness, and health.
Sun exposure
Theoretically, this is possible, but in practically (in humans), it has not yet been proven. It is possible that exposure to the sun may stimulate the bagus nerve.
Studies have shown that Alpha-MSH protects the rodents from damage due to a stroke. Prevention occurs by activating the vagus nerve, which impedes the inflammation process 30, 31.
When alpha-MSH is injected into the brain, it causes moderate excitation of the vagus nerve in some conditions 32.
Exposure to the sun boosts alpha-MSH synthesis. However, saying that sun exposure can stimulate the vagus nerve would practically be a long stretch 33.
Fasting
Reducing calories, as well as fasting intermittently causes an increase in heart rate variability, a factor believed to be a marker of vagal tone 34.
Intermittent fasting is believed to improve heart rate variability. However, this claim has not been verified by any clinical trials.
According to a particular theory, the vagus nerve might initiate a reduction in metabolism during fasting. According to the theory, the vagus can detect a shortfall in blood glucose level and a decrease in chemical and mechanical stimuli from the gut. This increases vagal impulses from the liver to the brain, which tones down the metabolic rate 35.
Results from animal studies indicate that hormones like NPY increases while CRH and CCK decreases during fasting 35.
The reverse may be the case after eating. Satiety signals from the gut appears to boost sympathetic activity and stress responsiveness (high CRH, CCK, and low NPY) 35.
The vagus nerve also increases the sensitivity of animals to estrogen during hunger states. A study conducted on female rodents shows that fasting increases the number of estrogen receptors in certain regions of the brain (PVN and NTS), which may be mediated by the vagus 36.
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