Episode 80 - Vagus Nerve

The vagus (vagal) nerve is one of 12 cranial nerves that connect the brain and body. It is known as cranial nerve X (representing the 10th cranial nerve). The vagus nerve is the longest of the 12 cranial nerves.

It extends from the brain stem and splits off into many branches that extend down through the neck to the vital abdominal organs.  

The vagus nerve acts as an information superhighway to the brain. The left vagal nerve runs down the left side of your neck, and the right vagal nerve runs down the right side. The vagus nerve extends from the brain to the large intestines: down the neck, through the chest, around the heart, around the lungs, and through the abdomen and intestines.

The vagus nerve provides signals from the brain to the body, regulating our:

• Heart rate
• Taste
• Speech
• Skin sensations
• Muscle sensations
• Immune response
• Respiratory rate
• Blood pressure
• Mucus production
• Saliva production
• Digestion
• Frequency of urination
• Mood

It is a critical part of the autonomic nervous system, specifically the parasympathetic.

The autonomic nervous system has two main divisions:

• Sympathetic
• Parasympathetic

 

The vagal nerve is the primary component of the parasympathetic nervous system (PNS), also known as the "rest and digest" or "growth and healing" part of the nervous system. The PNS de-stresses or calms things down, whereas the sympathetic nervous system (SNS) is what revs things up. For example, our survival "fight or flight" response is initiated by the SNS. Both divisions of the nervous system are necessary. The key is balance between the two.

The sympathetic nervous system tells the body to enter fight-flight-freeze mode when needed. The parasympathetic signals the rest and digest, relax & growth mode. It’s the key to unlocking the relaxation response. In recent years, researchers discovered that the vagus nerve also puts the brakes on inflammation, a key player in the onset of nearly all chronic diseases, including those that affect cognition.

Scientists are discovering that the vagus nerve may also help promote and protect brain function.

Poor vagal health signs:

Physical Symptoms:

• Digestive Issues: Abdominal pain, bloating, nausea, vomiting, acid reflux, and changes in bowel habits (constipation, diarrhea). 
• Cardiovascular Issues: Changes in heart rate (bradycardia or tachycardia), low or high blood pressure, fainting or dizziness. 
• Gastrointestinal Issues: Difficulty swallowing, loss of gag reflex, and hoarseness or loss of voice. 
• Other: Muscle aches, headaches, fatigue, and brain fog. 

Mental Health Symptoms:

• Anxiety and Depression: Vagus nerve stimulation has been shown to reduce cortisol levels, promoting a reduction in stress and anxiety, which can lead to improved mood, better sleep, and reduced stress. 
• Fatigue and Chronic Pain: vagal dysfunction can contribute to fatigue and chronic pain. 
• Other: Other mental health symptoms like panic attacks and a feeling of being overwhelmed. 

Factors Contributing to Vagal Dysfunction:

• Stress: Chronic stress can negatively impact vagal tone, leading to dysfunction. 
• Inflammation: Chronic inflammation can affect the vagus nerve's ability to function properly. 
• Diet: A poor diet can contribute to inflammation and digestive issues, which can affect vagal function. (Yuka App)
• Infections: Infections can cause inflammation and damage to the vagus nerve. 
• Other: Brain trauma, stroke, and certain medical conditions can also affect the vagus nerve. 

Improving Vagal Nerve Health: