What is the Vagus Nerve?
Jake Newby
| 3 min read
We don’t typically talk or even think about our vagus nerve. It helps control some of our body’s most basic, involuntary functions. When we breathe, digest food, sweat and experience heart rate fluctuations, the vagus nerve is largely responsible. It influences nearly every internal organ.
Also known as the vagal nerve, the vagus nerve is one of the main nerves of the parasympathetic nervous system, which is a network of nerves that helps the body relax after it encounters danger or stress. The vagus nerve begins in the medulla oblongata in the lower brainstem and split off into many branches that extend down through the neck and into the chest, heart, lungs, abdomen and digestive tract. Visualize it as a tree, with limbs that run down and interact with all other parts of the tree. This is a metaphor for the vagus nerve's reach on every vital organ system in the body.The vagus nerve makes up 75% of the nerve tissue in the parasympathetic nervous system, making it the longest of any of the 12 cranial nerves.
What does the vagus nerve do?
While the sympathetic nervous system regulates the body’s “fight or flight” response, the parasympathetic nervous system essentially helps the body come down from that response and begin to rest and relax. The rhyming phrases “rest and digest” and “feed and breed” are often used to help people remember what the parasympathetic nervous system does best. And the vagus nerve is like the conductor of the entire system.The involuntary sensory and motor functions the vagus nerve helps regulate include:
- Digestion
- Frequency of urination
- Heart rate, blood pressure and respiration (breathing).
- Immune system responses.
- Mood
- Mucus and saliva production
- Skin and muscle sensations.
- Speech
- Taste
Signs and symptoms of vagus nerve problems
Many symptoms of vagus nerve dysfunction overlap with symptoms of other conditions, simply because the vagus nerve affects so many bodily functions. Signs that something could be wrong with it include:
- Abdominal pain and bloating
- Acid reflux
- Changes to heart rate, blood pressure or blood sugar
- Dizziness or fainting
- Hoarse voice
- Loss of appetite or a feeling of fullness after eating minimal food
- Nausea and vomiting
- Trouble swallowing
- Unexplained weight loss
- Wheezing
More research is needed to see how and to what extent vagus nerve issues impact mental health, chronic mood disorders, chronic headaches and even Alzheimer’s disease. Conditions like gastroparesis and vasovagal syncope are commonly traced back to the vagus nerve.
How to keep your vagus nerve healthy
Some of the same healthy habits or lifestyle choices you adopt to become generally healthier can also strengthen your vagus nerve. They include:
- Cold water immersion therapy
- Exercise
- Massages
- Listening to music
- Meditation
What is vagus nerve stimulation?
Vagus nerve stimulation involves using electrical impulses to stimulate the nerve because vibrations stimulate the parts of the vagus nerve found in the back of the throat. Many devices that apply this treatment are approved by the U.S. Food and Drug Administration (FDA).Research done on the vagus nerve indicates that stimulation with electrodes can potentially help improve mood and soften symptoms in individuals who suffer from treatment-resistant depression. It can also treat conditions like epilepsy, diabetes, posttraumatic stress disorder and inflammatory autoimmune conditions such as Crohn’s disease and rheumatoid arthritis.Talk with your health care provider if you have questions about your health. They can advise you on a course of treatment that’s right for you.Read on:
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Photo credit: Getty Images
