The vagus nerve (pronounced the same as Vegas) is so named from the Latin word for wandering as it is one of the longest and most widely branching nerves in the human body.
The vagus nerve picks up signals from every ‘sensing area’ of the body with a particular focus on the walls of the blood vessels throughout the body and the digestive system. In fact, as one scientist quoted - “every year somebody finds a new organ or system that [the vagus nerve] talks with. There’s a massive bioelectrical and biochemical series of events that the vague nerve is responsible for, and all that is impossible to map.”
The vagus nerve regulates our heart and breathing rates, blood pressure and blood flow; it controls gut movements (motility), secretions, inflammatory responses, the integrity of the gut lining and even appetite. Reflexive movements like coughing, gagging and vomiting are all controlled by the vagus nerve.
If a virus, bacteria, toxin, parasite or other unwelcome visitor is present the vagus nerve will let your brain know that. If you’ve cut your finger, are feeling hot or cold, or have just eaten something – the vagus nerve will let your brain know that too.
It must therefore surely follow that if the activity of the vagus nerve (known as ‘vagal tone’) is impaired in some way it has the potential to cause a wide range of health issues.
Because the vagus nerve reduces inflammation by regulating our immune system, continued impairment of this function may lead to systemic inflammation which can cause arthritis, diabetes, heart disease, stroke, Alzheimer‘s, respiratory disease, obesity and other health issues association with inflammation. An over-active immune system can lead to auto-immune diseases like lupus, rheumatoid arthritis, Hashimoto’s thyroiditis, psoriasis.
When stress is triggered our heart rate goes up, we breath faster, we can feel jittery and shakey, but once we are out of the ‘danger zone’ the vagus nerve jumps in to counteract these stress responses. This is a perfectly normal process for most but if the vagal tone is poor we can be stuck in ‘fight or flight’ or ‘freeze’ mode, anxiety is easily triggered or panic attacks occur. In this case the stress hormone, cortisol, can be permanently raised affecting our bones, brains, muscles and body fat. There is now evidence to suggest that improving vagal tone can be beneficial for post traumatic stress disorder.
When the vagus nerve over-reacts to stress it can causing fainting as it causes the blood pressure to drop quickly and dramatically. This is the most common cause of fainting.
The vagus nerve sends information to the brain about the content and condition of the gut. It has long been established that gut health and the microbiome are important for mental health and studies have shown that stimulating the vagus nerve can be extremely effective in combating depression. Low vagus nerve activity is also associated with dementia, cognitive decline and poor memory.
There are studies that show long-term chronic illnesses like Fibromyalgia and Chronic Fatigue Syndrome (ME) are often associated with poor vagal tone.
So, how do you know if you have an ’imbalance’ with your vagus nerve? If you suffer with any of the conditions mentioned above, that does seem a likely indicator, however, illness and symptoms don’t appear immediately when something is not right in our bodies. Of course, we can just have a very minor imbalance which is asymptomatic and doesn't give any noticeable problems. There is a simple kinesiology test which can identify a vagus nerve imbalance, and this can also be checked to see if it is associated with any particular symptom, organ or system in the body (this will show even if there are no symptoms present). Further muscle response testing reveals what treatment is required to begin the healing process.
The great news is that we can all do simple things ourselves to maintain vagal tone and you can find my guide for some of these activities and exercises by clicking here.
Please do share this article with anyone you think will benefit too.