What a Gut Disorders Therapist Wants You to Know About the Vagus Nerve
By Dr. Lienna Wilson, Licensed Psychologist | Vagus Vitality
Most people don't connect a stomachache to their nervous system. Unfortunately, people with gut disorders, like irritable bowel syndrome or functional dyspepsia, experience that connection every day. That is because the gut and the brain are in constant communication through the vagus nerve, which carries signals in both directions.
To learn more about this topic, I had the pleasure of interviewing Katie Davis, LCSW, a therapist at GI Psychology, who is trained in evidence-based gut-brain therapies. She works with adults and adolescents living with gut disorders (also called disorders of gut-brain interaction or DGBI), structural GI disorders, such as Inflammatory Bowel Disease (IBD), and chronic pain. Katie's clinical work sits at the intersection of the gut and the nervous system, so I asked her to walk through how she explains this connection to clients, where the vagus nerve fits in, and what she recommends people try first.
What Is the Gut-Brain Axis
Katie starts most conversations with clients by introducing the enteric nervous system, the network of neurons lining the gut that is sometimes called the “second brain.” It operates semi-independently from the brain, but the two stay in constant two-way communication, what Katie calls “a bidirectional communication highway,” or the gut-brain axis (Cryan et al., 2019). Katie points to everyday examples that make this concrete for clients: the queasy stomach before a big presentation, the sudden urge to use the restroom before a stressful meeting, the loss of appetite when feeling stressed before meeting someone new. These aren't coincidences. They're the gut-brain axis working in real time.
Where the Vagus Nerve Fits In
The vagus nerve runs from the brainstem down to the large intestine, and it is one of the main channels this communication travels through. As part of the autonomic nervous system, it helps the body shift between the “rest and digest” state of the parasympathetic nervous system and the “fight or flight” state of the sympathetic nervous system. Katie explains that many clients with irritable bowel syndrome (IBS) or functional dyspepsia are living in a state of hypervigilance — constantly scanning their body for discomfort or their environment for threat — which often disrupts digestive function. “By using strategies aimed at nervous system regulation,” Katie says, “we can influence a sense of safety in which healthy digestive function is restored.”
That same vagal tone shows up outside the gut too. “Healthy vagal tone allows an individual to both respond to stress and recover,” Katie says, while low vagal tone is linked to a harder time doing either, a pattern she sees in both DGBI and anxiety disorders. Because gut function and mood are governed by many of the same neurotransmitters, disruption in one can influence the other. According to Katie, clients “may feel that they're either 'always on' or shut down and have a difficult time utilizing strategies which reliably influence their mood.”
How Clients Can Regulate Their Nervous System
“Safety is the language of the nervous system,” Katie tells her clients. When it senses danger, real or perceived, it prepares the body to fight, flee, freeze, or fawn, which can mean shutting down digestion because, as Katie puts it, digestion “is not the most important function in a life or death situation.” When it senses safety, the opposite happens: heart rate and blood pressure drop, and digestion is allowed to resume.
To help clients build that sense of safety, Katie draws on diaphragmatic breathing (Lehrer & Gevirtz, 2014), gut-directed hypnotherapy, attentional training, and positive expectation. Gut-directed hypnotherapy in particular has research behind it. Reviews of the evidence show meaningful improvement in GI symptoms for both children and adults (Palsson, 2015), and a more recent pilot study found that hypnotic suggestions emphasizing safety specifically improved outcomes for clients with DGBI (Damis & Hamilton, 2020).
A Common Misconception about the Gut-Brain Connection
One misconception Katie corrects often is the idea that GI symptoms and anxiety are competing explanations, as though a diagnosis has to be either physical or psychological. Historically, medicine treated the mind and body as separate systems, and many clients with DGBI have been told, directly or indirectly, that their symptoms are mostly in their head. “The brain is only a piece of the puzzle,” Katie says. The most effective, evidence-based treatments for DGBI target the gut-brain axis directly, most often through a combination of cognitive behavioral therapy for GI (CBT for GI) and gut-directed hypnotherapy (Palsson, 2015). That combination addresses both hypervigilance, the constant scanning for symptoms or bracing for a flare, and visceral hypersensitivity, where the nerves become more reactive and ordinary digestive sensations start registering as pain.
Where to Start If You Want to Support Your Gut-Brain Connection
If you want to start supporting your own gut-brain connection today, Katie recommends diaphragmatic breathing as a simple, evidence-informed place to begin:
Put one hand on your chest and one on your abdomen. As you breathe, the abdomen should move, expanding on the inhale and contracting on the exhale, while the chest stays relatively still. Inhale into your abdomen for a count of 4. Hold for 4 counts if that feels comfortable (this part is optional). Exhale for a count of 6. “It's important that the exhale is longer than the inhale,” Katie says, “as the body relaxes even more deeply on the exhale.” Repeat for 5 to 15 minutes.
If you've been struggling with a gut disorder, there is hope. Treatment doesn't have to come from a medical perspective alone. As Katie's work shows, psychological tools, including gut-directed hypnotherapy, CBT for GI, and diaphragmatic breathing, can also meaningfully support the gut-brain connection.
About Katie Davis: Katie Davis is a Licensed Clinical Social Worker trained in evidence-based gut-brain therapies, including CBT for GI and gut-directed clinical hypnosis. She provides individual psychotherapy to adults and adolescents with disorders of gut-brain interaction (DGBI), IBD, and chronic pain at GI Psychology.
A note on this piece: gut-directed hypnotherapy and CBT for GI are typically delivered by a trained clinician as part of a broader treatment plan. Nothing here is a substitute for individualized care. If you're dealing with persistent GI or anxiety symptoms, talk to your doctor or a qualified therapist about what's right for you.
References
Cryan, J. F., O'Riordan, K. J., Cowan, C. S. M., Sandhu, K. V., Bastiaanssen, T. F. S., Boehme, M., ... & Dinan, T. G. (2019). The microbiota-gut-brain axis. Physiological Reviews, 99(4), 1877–2013. https://doi.org/10.1152/physrev.00018.2018
Damis, L. F., & Hamilton, M. S. (2020). Impact of hypnotic safety on disorders of gut-brain interaction: A pilot study. American Journal of Clinical Hypnosis, 63(2), 150–168. https://doi.org/10.1080/00029157.2020.1794434
Lehrer, P. M., & Gevirtz, R. (2014). Heart rate variability biofeedback: How and why does it work? Frontiers in Psychology, 5, 756. https://doi.org/10.3389/fpsyg.2014.00756
Palsson, O. S. (2015). Hypnosis treatment of gastrointestinal disorders: A comprehensive review of the empirical evidence. American Journal of Clinical Hypnosis, 58(2), 134–158. https://doi.org/10.1080/00029157.2015.1039114