Inside your body is an amazing nerve called the vagus nerve, or cranial nerve X. It is the largest nerve in your body. It is nicknamed “the Wanderer” because of how long it is and how many organs it travels to. It provides invaluable connection to almost all your internal organs and helps bring homeostasis to stress function. When the tone of this nerve is dampened, it impacts vast activities in your body that lend to a decline in health. It is important to support and protect this great “Wanderer” for optimal health.
The vagus nerve is a network of magnificent, intricate connections that maintain homeostasis of the neuro-endocrine-immune systems and parasympathetic (rest, relax, repair) autonomic nervous system.
The vagus nerve originates in your brainstem as a pair of nerves, one traveling down on the left side of your neck and down the right side. It then travels down into the trunk of your body where it innervates your throat, esophagus, lungs, heart, spleen, liver, stomach, pancreas, gallbladder, kidney, bladder, small intestine, and the first part of the colon.
The vagus nerve is a two-way masterful communication system. Its most important action is to bring information from the internal organs to your brain, which accounts for about 80 percent of nerve fibers that travel upward. The remaining 20 percent of its fibers travel downward with signals from the brain to the internal organs.
The vagus nerve provides nerve signals for swallowing, vocalization, and saliva secretion. It affects heartbeat, heart rate, and respiration. It modulates blood pressure and supports blood vessel dilation as it helps balance against sympathetic (fight, flight, stress) nervous system tone.
Branches of the vagus nerve affect stress hormone regulation and activation related with the hypothalamic-pituitary-adrenal (HPA) axis. It buffers against sympathetic (stress) nervous system chemicals and inflammatory compounds.
Immune Activity and Inflammation Management
The vagus nerve directs immune activity and inflammation management. It calms down the production of pro-inflammatory cytokines by immune cells in the spleen, which helps manage inflammatory response from the respiratory tract and immune system. Normal vagal nerve activity dampens pain signals in the brain and spine and reduces pain-related behavior.
Vagus Nerve and Gut Health
The vagus nerve is vastly involved with numerous aspects of digestion, bowel motility, and gut-immune health. It innervates the stomach, pancreas, liver, and small intestine, which affects your nutrient metabolism and absorption.
The vagus nerve talks with the enteric nervous system, or the “second brain”, This is a vast network of 100-500 million neurons in your gut from the esophagus to the anus that relies on vagus nerve activity
Over 50 compounds, including the hormone leptin have so far been identified in support of vagus system communication. This affects energy metabolism, feeling hunger and satiation as well as secretion of stomach acid, digestive enzymes, and stomach volume capacity and inflammation management.
The predominant compound used by the vagus nerve and enteric nervous system is choline or acetylcholine. Because of its heavy reliance on choline, this connection has been dubbed the “cholinergic anti-inflammatory pathway”.
Vagal nerve activity also profoundly affects the connection between the brain and gut microbiome. Gut flora use the vagus nerve to communicate to the brain. The magnificent vagus nerve can distinguish between beneficial versus non-beneficial and potentially pathogenic bacteria in the gut, which modulates immune-inflammatory activity.
Healthy gut flora and probiotics like Lactobacillus rhamnosus positively impact the brain-gut communication system. A healthy balance leads to positive mood and cognitive functions via the vagus nerve cholinergic anti-inflammatory pathway. An imbalanced gut flora stresses vagal activity connection, which promotes negative mood stress and cognitive challenges.
High Fat and High Carb Diets
Research published May 2021 showed that diet affects vagus nerve activity. In this study, rats were fed a high-fat or a high-carb diet for several months to simulate the Western diet. Results demonstrated both diets impaired vagus activity, as seen with diminished satiety and larger stomachs. Repetitive overconsumption of high fat and/or high carb foods desensitized vagal receptors that monitored stomach volume and distension. Neural feedback mechanisms that normally send a signal of feeling full were impaired.
Research in humans also demonstrated that chronic over-eating of calorie-rich diets reduced vagus nerve sensitivity to signals. “Numbness” to the signals was sufficient to cause overeating and obesity.
Activities that Support the Vagus Nerve
There are many ways to gently activate the vagus nerve. These include:
Humming, gargling, and gag reflex. Humming, gargling, and stimulation of the gag reflex activate the nerve. Use a word like “ah”, “oh”, “om” and hold the vibration as long as you can while you exhale.
You may also gargle with water for 20-60 seconds. Strive to gargle to the point that your eyes water.
To stimulate the gag reflex, gently touch the left and right side of the soft palate area with a finger, Q-tip, or tip of the toothbrush. A good time to do this is when you brush your teeth.
Deep belly breathing. Deep belly breathing is easy to do any time. Inhale through your nose for 5 seconds. Hold for 6 seconds. Then exhale for 7 seconds out through your mouth. 5-6-7 inhale-hold-exhale. Do this ten times. Make sure to breathe in deeply so your diaphragm engages, and belly expands outward. Short-shallow breaths through your chest and upper body do not engage the vagus nerve and parasympathetic nervous system.
Cold water exposure. Cold water showers or cold water to the face activates the vagus nerve. Try to finish your shower with 30-60 seconds of cold water. Use as cold of water as possible and do the belly breathing exercise at the same time. As you acclimate to the shock of the cold water over the course of several days, gradually increase the amount of time in a cold shower. Do this once per day.
Ear-tragus tapping. There is a small branch of the vagus nerve that goes to your ear. You activate, or send signal to the vagus nerve, by tapping with a toothpick or gently rubbing the cartilage in front of the auditory canal called the tragus. There are acupuncture meridians in that area.
Meal timing and fasting. Allow 4-6 hours between meals and fast overnight for 10-12 hours. This allows time for digestion to occur and puts less strain on the digestive tract and vagus nerve.
Body work. Chiropractic adjustments, massage therapy, acupuncture, yoga, and pilates support vagus nerve activation. Seek regular care at least once a month or more to help your nervous system and vagal nerve activation.
Heart Rate Variability. You can measure heart rate variability with various apps. This provides insight into the connection between vagal nerve tone and heart rhythm. High levels of heart rate variability are associated with good health and vagal nerve activity. Low heart rate variability is linked with poorer health and reflects low vagal tone. You can learn more in the articles Heart Rate Variability – Why You Should Know Yours and Stress Induced Burnout: The Path Back to Happiness.
Nutrition for the Vagus Nerve
High calorie, nutrient poor diets fail to healthfully support the vagus nerve. The standard American high-fat, high carb diet instead numbs vagal nerve activity. Start with a healthy diet that includes organic, free-range animal proteins. Plant-based diets will not provide enough choline.
Adequate Intake is Lacking
A major dietary study, National Health and Nutrition Examination Survey (NHANES) 2009-2012, showed that only 11 percent of the participants obtained the daily recommended adequate intake for choline.
Choline is a B vitamin-like essential nutrient found primarily in beef liver and eggs, with moderate dietary amounts in beef, pork, fish, and dairy. Small amounts are found in nuts, seeds, and beans, with very little found in fruits and vegetables.
Adequate intake (AI) of choline for adult men and adult women is 550 mg/day and 425 mg/day respectively. Pregnant and breastfeeding women need 450-550 mg/day. Infants 0-12 months of age need 125-150 mg/day. Toddlers 1-3 years need 200 mg/day, children 4-8 years 250 mg/day, and 9-13 years require 375 mg/day.
Low estrogen levels and PEMT gene SNPs or polymorphisms may increase dietary choline requirements. You can find out if you have PEMT gene SNPs with a methylation function test or with one of the commercially available gene tests for health and ancestry. In addition, fatty liver congestion is related to insufficient dietary choline intake.
The vagus nerve requires nutrients to work. Acetylcholine is the predominant substance used by the vagus nerve. Very small amounts of choline can be made by your liver, but it is not enough to sustain vital functions. You must get choline from your diet or use supplemental sources.
Alpha GPC is a special fat that is readily absorbed from the digestive tract and can cross the blood brain barrier. It is used to make acetylcholine. Acetyl-l-carnitine, the activated form of the amino acid l-carnitine, can be transformed into acetylcholine. In addition, pantethine, the active form of vitamin B5 provides coenzyme A (CoA). CoA is necessary to make acetylcholine.
The human body is a beautiful, immeasurable complex creation. In recent years, the depth of knowledge on vagus nerve functions and its impact on health has been tremendous. We now have a much greater understanding of how to functionally impact the vagus nerve.
You can use these tools and nutrients like choline/alpha-glycerylphosphorylcholine (alpha-GPC), pantethine, and acetyl-carnitine to help support vagus nerve activity. Make sure to support your gut flora with beneficial probiotics in foods or supplement.
Thankfully, you don’t have to think about the how and why of the vagus nerve, but you do need to provide your body the nutrients and self-care for vagus nerve activity. If you lack adequate choline intake, the benefits of the physical activities that activate vagal nerve activity will be compromised. Nearly 9 out of 10 Americans do not consume enough choline in their diet based on the NHANES study. Odds are you are one of them. Put the odds in your favor to support your mighty vagus nerve.