The Vagus Nerve


What is the Vagus Nerve?

 Known as the wanderer, the vagus nerve or cranial nerve X (10) is a long nerve that runs from the cranium to the colon, connecting and controlling all of the organs in between. The vagus nerve is the main component of the parasympathetic nervous system, which oversees a vast array of crucial bodily functions, including control of mood, immune response, digestion, heart rate, etc. 

The parasympathetic nervous system is also known as the rest and digest response because it restores the body back into balance after sympathetic stimulation, or fight or flight. When the body is in a sympathetic state, its primary focus is stress and being able to flee from a situation, if necessary. In a parasympathetic state, the body is calm, composed and it is able to focus on resting and digesting. Essentially, the vagus nerve is a communication superhighway between the gut, the brain, and beyond.

The Gut-Brain Axis

An important analogy to keep in mind is that when the gut is on fire, the brain is on fire,and vice versa. This is because of the intimate connection of the gut and brain through the vagus nerve. It establishes one of the main connections between the brain and the gastrointestinal tract and sends information about the state of the inner organs to the brain through afferent nerve fibers. 

This communication network is known as the gut-brain axis

The vagus nerve is responsible for giving you a “gut feeling” about a situation or something that is bad, unhealthy, or a dangerous idea. 

Vagal Tone

The activity, or tone of the vagus nerve is crucial for optimal function. Increasing vagal tone activates the parasympathetic nervous system. Having a greater vagal tone means the body can quickly relax after a period of stress. When vagal tone is weak, symptoms can arise. 

Some signs and symptoms of vagal tone insufficiency are:

  • A horse voice

  • Difficulty swallowing

  • Deficient gag reflex

  • Deviation of the uvula way from the side of the damaged nerve

  • Abnormalities in heart rate and heart rate variability

  • Gastrointestinal symptoms

  • Gastroparesis 

  • Loss of appetite

  • Nutrient deficiencies

  • Neurotransmitter dysfunction, anxiety, and/or depression

  • Blood sugar dysregulation

  • Metabolism dysfunction

  • Pain syndromes

  • Thyroid imbalances

  • Adrenal dysregulation

  • Detoxification pathway impairment

 

Risk Factors

It’s important to understand what causes the vagus nerve to become compromised in the first place. Anything that is stressful on the body (physically, emotionally, or spiritually) and left unchecked can eventually damage the vagus nerve. 

This could be inflammatory food choices, gut imbalances, various infections like Lyme, hormone imbalances, blood sugar dysregulation, poor sleep habits, and exposure to environmental toxins such as mold, heavy metals, or chemicals. 

Likewise, anything the body deems life-giving (physically, emotionally, or spiritually) will strengthen the vagus nerve.

Oftentimes, we see trauma contributing to damage in vagal tone, especially adverse childhood experiences (ACEs). Additionally, negative thoughts and brain patterns can contribute to vagal nerve dysfunction. 

Also, our brains can be wired in negative patterns as a result of going through hard things in life. It seems that the hardship of walking through chronic illness can further aggravate negative brain patterns and vagal dysfunction.

Strong Versus Stressed

Why would you want to activate the vagus nerve? High vagal tone has numerous benefits including helping to regulate blood glucose, reduce inflammation levels, improve digestion, boost immune function, support detoxification, improve metabolic function, calm stress, and foster better mental health and neurotransmitter function, etc.

And weak vagal tone? That can lead to the opposite situations.

There is no doubt about it, the past couple of years have been a season of stress and anxiety. As we discuss the vagus nerve, it is important to understand that it is deeply impacted by stress. When you are stressed, vagal nerve function diminishes allowing for a multitude of unwanted symptoms. Likewise, when we are under significant stress, strengthening vagal tone can decrease our fight or flight response and the subsequent cascade of inflammatory stress hormones. 

Doing activities and exercises for the vagus nerve will help our bodies successfully navigate stress. 

How to Tone the Vagus Nerve

By understanding the workings of your vagus nerve, you can learn to work with your nervous system rather than feel at the mercy of it! 

Deep breathing

Deep diaphragmatic breathing, box breathing, or pranayama breathing can tone the vagus nerve. Make sure your belly expands outwards and you focus on a long, slow exhale for maximum benefit. These breathing techniques are particularly helpful tools to employ during moments of stress.

Mindfulness

Taking part in prayer, meditation, and mindfulness can positively impact the vagus nerve. Not only do these strategies combat stress and anxiety, but they can increase heart rate variability and parasympathetic activity. 

Cold stimulation

Research shows that acute cold exposure will activate the cholinergic neurons that are part of the vagus nerve pathways along with stimulating the vagus nerve. Short 1 to 2 minute bouts of cold shower water increases stimulation of the vagus nerve by activating the parasympathetic nervous system. You can also spend time outside in the cold in minimal clothing or plunge into cold water for therapeutic effect. 

Singing, Humming, and Gargling

The vagus nerve is connected to your vocal cords so singing, humming, chanting, and gargling can activate the vagus nerve. Keep in mind, it must by robust, loud gargling for maximum vagal nerve stimulation. 

Exercise

The health benefits of exercise are widely established so it is probably not surprising that physical activity also tones the vagus nerve. Find an activity you enjoy and stay consistent for optimal vagus nerve stimulation.

Massage

Receiving regular therapeutic massages on various parts of the body can help with vagal nerve tone. Reflexology can also stimulate the vagus nerve, increase heart rate variability, and decrease the “fight or flight’ stress response. Even giving yourself a foot massage can help restore vagus nerve function. 

Chiropractic Care

Chiropractic care and spinal manipulation regulate the autonomic nervous system at the peripheral level and its projections to the central nervous system. In particular, chiropractic adjustments may activate the parasympathetic system and therefore downregulate the activity of the sympathetic system. 

Supporting the Gut

Since the gut and brain are connected through the vagus nerve, supporting the gut can not only tone the vagus nerve, but also support the brain. Supplementing with probiotics, prebiotics, and fiber can support the vagus nerve because the gut microbiota impacts the vagus nerve. 

Omega 3 Fatty Acids

Omega 3 fatty acids are essential to consume because the body cannot make them on its own. Consuming omega 3 fatty acids from wild caught fatty fish, flaxseed, and walnuts or supplementing with an omega 3 supplement can improve vagal tone and vagal activity. Studies show omega-3 fatty acids increase heart rate variability and conversely stimulate the vagus nerve 

Laughter and Spending Time with Others

Social interaction is foundational to overall health, especially vagal nerve function! Researchers have discovered that increased positive social interactions are directly correlated with increased vagal tone. Make sure you prioritize being with others and enjoying life!