The Vagus Nerve, Stress, and Breathing
Feeling like your body’s stress response is firing at high speeds these days? You may need to spend time engaging your vagus nerve. The vagus nerve is directly connected to the stress response and plays a major role into how we face stress, reduce inflammation, and heal our gut.
The vagus nerve (cranial nerve x) is the main nerve of the parasympathetic part of the autonomic nervous system. This means it plays a large role in the rest and digest part of the nervous system. The vagus nerve has an important role of communication between the brain, gut, cardiovascular system, and the immune system. The nerve is located from the brainstem down through the chest and into the abdomen, where it then goes to multiple organs.
The vagus nerve is a communicator. The brain sends signals to the organs of the chest and abdomen, as well as the gut and other organs to the central nervous system. The vagus nerve signals the brain to produce neurotransmitters and hormones. It coordinates the response to regulate stress reactions and also helps to keep inflammation down. It does this by having a parasympathetic relaxation response, which slows down breathing and heart rate, while stimulating digestion, promoting relaxation, and making you feel calm. To coordinate this response, the vagus nerve releases the neurotransmitter acetylcholine. This means your gut, brain, behavior, and immune system are all connected.
Low Vagal Tone
When we begin to understand how our bodies work, we can know how and why to treat them better. As the vagus nerve plays a major role for the body, the health of this nerve is important for your brain and your immune system. When we begin a Yoga and Ayurvedic practice, our single pointed focus is on settling into the body and opening to the inner Self. If we do not access and relax our body through breathing, then our stress and immune system can become compromised.
The strength of the vagus nerve response is known as vagal tone. Chronic inflammation has been linked to low vagal tone. A reduced vagal tone can trigger the production of pro-inflammatory cytokines (substances secreted by inflammatory cells) and can lead to an increase in sympathetic nervous system activity and stress hormones, such as cortisol, contributing further to overall inflammation.
Through working on strengthening our vagal tone we can have a balanced immune system, a calm body and mind, and reduced stress and inflammation. This can be hard to practice if we don’t have an understanding of how stress works in the body.
The Stress Response
The Autonomic nervous system (ANS) is responsible for reacting to our environment. We respond in one of two ways: either the mind-body perceives threats and initiates the flight/fight/freeze response, or perceives safety and maintains homeostatic balance where rest, repair, and growth can happen. These two response options are part of ANS known as the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
Whether you’re walking on the beach or being chased by a tiger, these real or imagined threats initiate the flight, fight, or freeze response, controlled by the SNS. The SNS sends stress hormones into the bloodstream, causing increased heart rate and blood pressure, respiration, contraction of muscles, and depressed non-essential functions like digestion. In this perceived threatening state, our limbic system, or the fear circuit, dominates. Instead of drawing on the prefrontal cortex and other areas of the brain to respond with reasoning and effective communication, social behavior becomes limited to survival strategies and we can react with aggression, withdrawal, or avoidance. Without practice it can be easy to fall into old coping mechanisms and react to situations.
In a perceived safe environment, our PNS initiates a relaxation response, which decreases heart rate and blood pressure, decreases respiration, reduces muscle contraction, and allows repair and restore functions such as digestion to take place. This can counterbalance the SNS. We can do this by focusing on pranayama (breathing) exercises to calm down our nervous system. In this state, we can free up higher cognitive functioning and enable a more complex and flexible range of behavior. If we have deep trauma it can be hard to get to this place. However, an Ayurvedic and Yoga practice can help heal our gut, strengthen vagal tone, and allow for us to calm our nervous system down.
Ayurveda does this in three ways: 1) Healing the gut to treat the brain through food 2) Yoga, meditation, and pranayama (breathing exercises) 3) Abhyanga and self-massage on the abdomen to strengthen vagal tone and reduce stress.
Breathing to Strengthen Vagal Tone
Yoga and Ayurveda grew from the same ancient seed. While they have grown to become trees with diverse branches and paths, the root of them is grounded in the knowledge that we are one with nature. As trees produce oxygen for us to breathe, which is the essence of life on earth, Ayurveda and Yoga emphasize prana (breath or life-force energy) to connect our brain, mind, and body.
As we talked about a minute ago, the ANS is how we react to our environment. As the name suggests, “autonomic” implies that these responses are often “independent” of the conscious mind. Prana or breathing is one part of the autonomic nervous system that can be controlled. It can therefore be used to help facilitate which response is evoked during stressful situations.
As prana is essential for life, the brain responds to the respiratory system with urgency. This is why yogic breathing can make such a strong impact on the vagus nerve. Prana is the access point into our nervous system.
One pranayama (breathing) exercise that is suggested in Ayurveda and Yoga is Nadi Shodhana. Nadi Shodhana, or “alternate nostril breathing,” is a simple and yet very powerful technique to settle your nervous system down and connect your mind, body, and emotions. It is translated as “clearing the channels of circulation.” Nadi Shodhana has been used to quiet the mind and is helpful in calming anxiety, stress or trouble sleeping. There are a few different styles of Nadi Shodhana, but they all serve the purpose of creating balance in the nasal passageway and regulating the flow of air.
Benefits of Nadi Shodhana
Whether you’re nervous for a work presentation, an interview, or a hard conversation, Nadi Shodhana is a quick way to bring you back to center. It is a great exercise to do when feeling stressed, overheated, anxiety-ridden, or frazzled. The breath is the place for us to connect to our nervous system and restore a state of balance.
Other benefits of Nadi Shodhana:
Improves our ability to focus
Rejuvenates the nervous system
Supports lung and respiratory functions
Restores and clears the energetic channels
How to Do Nadi Shodhana
A few rounds of Nadi Shodhana is an accessible way to connect your mind, body, and brain.
Sit in a comfortable seat with your spine straight and your heart open.
Relax your left palm comfortably into your lap and bring your right hand just in front of your face.
With your right hand, bring your pointer finger and middle finger to rest between your eyebrows, lightly using them as an anchor. Some prefer to tuck the pointer and middle finger into your palm. Try out both ways to see what works best for you. The fingers we’ll be actively using are the thumb and ring finger.
Close your eyes and take a deep breath in and out through your nose.
Close your right nostril with your right thumb. Inhale through the left nostril slowly and steadily.
Close the left nostril with your ring finger so both nostrils are held closed; retain your breath at the top of the inhale for a brief pause.
Open your right nostril and slowly release the breath through the right nostil; pause briefly at the bottom of your exhale.
Inhale through the right side slowly.
Hold both nostrils closed (with ring finger and thumb).
Open your left nostril and release breath slowly through the left side. Pause briefly at the bottom.
Repeat 5-10 cycles of one complete cycle of Nadi Shodhana(directions from 5-9), allowing your mind to follow your inhales and exhales.
Consistency of your inhale and exhale can be helpful. For example, you can inhale for a count of five, hold, and then exhale for five. You can slowly increase the count depending on what works for your practice. Use this pranayama practice to restore balance and as a quick effective way to calm your nervous system.
Health is not about one treatment or one pill that can help your gut, stress, or inflammation. It is a lifestyle change of being present, tapping into our breath, and treating your mind, body, and behaviors as a whole ecosystem.