Is your vagus nerve ok?

If you feel like you’re stuck in ‘fight or flight’ mode, experiencing digestive issues, dizziness, palpitations. Sleep is poor and tiredness is there all the time. Tests at the doctors haven’t found anything specific but you just don’t feel right. It could be your vagus nerve.

The vagus nerve is the longest and most influential nerve of the parasympathetic nervous system, a branch of the autonomic nervous system often referred to as the body’s “rest and digest” system.

Running from the brainstem through the neck and chest to the abdomen, the vagus nerve connects the brain with major organs including the heart, lungs, and digestive system. Its primary role is to regulate autonomic functions.

The vagus nerve regulates autonomic functions such as slowing the heart rate, supporting digestion, modulating inflammation, and calming the nervous system. When vagal tone – a measure of vagus nerve activity – is healthy, the body can respond to stress efficiently and return to a state of calm with ease.

Vagus nerve dysfunction, sometimes described as low vagal tone, can present with a wide range of symptoms. These may include digestive issues such as bloating, constipation, or irritable bowel symptoms; cardiovascular signs like palpitations or dizziness; difficulty managing stress or anxiety; poor sleep; fatigue; and chronic stress.

Because the vagus nerve plays a crucial role in regulating multiple body systems, dysfunction can feel widespread and non-specific, making it challenging to identify.

There is not one specific, simple test that can be carried out to assess the vagus nerve. The GP is best placed to exclude other factors with known tests and refer on to specialists. As the vagus nerve has such wide reaching influence, specialist support may be best gained from different areas such as neurology, gastroenterology or cardiology depending on the symptoms presenting.

How can breathing influence the vagus nerve?

Breathing is one of the most effective and accessible ways to influence vagus nerve function. Unlike most autonomic processes, breathing can be consciously controlled, providing a direct pathway to communicate with the nervous system.

Slow, controlled breathing stimulates the vagus nerve, increasing the activity of the parasympathetic nervous system and reducing the dominance of the fight or flight response (the sympathetic nervous system).

During inhalation, heart rate naturally increases slightly; during exhalation, it slows. This variation, known as heart rate variability (HRV), is a marker of vagus nerve activity. Slow breathing, particularly with a longer exhale, enhances HRV and strengthens vagal tone.

Diaphragmatic breathing – breathing deeply into the lower ribs and abdomen rather than shallow chest breathing – calms the nervous system by stimulating the vagus nerve and therefore the parasympathetic response.

Practices such as nasal breathing, longer exhalations, and paced breathing (for example, inhaling for four seconds and exhaling for six) have been shown to reduce anxiety, lower heart rate, improve digestion, and support emotional regulation.

Over time, consistent breathing practice can retrain the nervous system, making it easier for the body to shift out of stress and into recovery even outside of formal exercises.

If you feel stuck in fight or flight mode, experiencing symptoms of vagus nerve dysfunction, breathing techniques offer a low-risk, empowering tool to support healing.

While breathing alone may not address all underlying causes, bringing some calm into your day to day is a good place to start. By improving vagal tone, good breathing supports better communication between the brain and body, promoting balance, calm, and improved overall wellbeing.

Get in touch to see how Breathe and Move techniques can help.

Written by Jennie Harmsworth. Having qualified with a degree in Physiotherapy, Jennie spent more than 10-years working in intensive care and post-surgical rehabilitation at both University College London Hospital (UCLH) and Guys and St Thomas’ Hospital.

As a vastly experienced respiratory physiotherapist, Jennie has specialist expertise in dysfunctional breathing, breathlessness management, airway clearance and chronic cough as well as a range of other respiratory conditions such as Asthma, COPD and bronchiectasis.