Gut-Brain Connection - the Power of the Vagus Nerve

Have you ever noticed how your stomach feels tied in knots when you’re stressed, or how you lose your appetite when something’s weighing on your mind? That’s the gut-brain connection at work. At the center of this two-way highway is a powerful nerve: the vagus nerve.

The vagus nerve runs from your brainstem through your neck and chest into your digestive organs. It’s a key player in the gut-brain axis, constantly sending messages between your gut and brain that influence mood, digestion, and inflammation. When the vagus nerve is active, your body shifts into “rest and digest” mode, slowing your heart rate, improving digestion, and helping you feel calm and grounded (Ali, et al., 2023).

When it’s underactive, your body stays stuck in “fight or flight” mode, tense, reactive, and ready for danger. Over time, this chronic stress state can take a toll on both your digestive health and your overall well-being.

How the Vagus Nerve Connects the Gut and Brain

The vagus nerve is the main communication line in the gut-brain connection, influencing everything from gut motility and enzyme secretion to emotional regulation and inflammation (Ali, et al., 2023). In fact, about 80% of the nerve fibers in the vagus send information from the gut to the brain, not the other way around! 

When this nerve is functioning well, the digestive system moves smoothly, nutrient absorption improves, and inflammation stays in check. But when it’s disrupted by chronic stress or inflammation, you may experience bloating, constipation, poor appetite, or anxiety (Breit, et al., 2018).

Why Chronic Stress Keeps Us in Fight-or-Flight

Our bodies evolved to handle acute stress like running from a lion or escaping sudden danger. In those moments, the sympathetic nervous system kicks in, flooding the bloodstream with adrenaline and cortisol. Once the threat passes, the vagus nerve helps the body return to calm balance (Nowacka-Chmielewska et al., 2022).

The problem? In modern life, the “lions” never go away. Instead, they look like emails, traffic, social media, deadlines, and constant noise. This keeps the stress response on far longer than it was meant to be. Chronic stress like this can disrupt digestion, raise inflammation, and contribute to chronic conditions such as IBS, fatigue, and autoimmune disease. 

The good news? You can retrain your body’s stress response by stimulating and strengthening your vagus nerve naturally (Breit, et al., 2018).

Functional Ways to Stimulate and Strengthen the Vagus Nerve

These simple, evidence-based techniques help your body shift from stress to calm (Bonaz, et al., 2016). They’re free, can be done almost anywhere, and support both gut health and nervous system balance.

1. The Physiological Sigh

Take a deep breath in through your nose, then take one more short “sip” of air at the top. Exhale slowly through your mouth until all the air is gone. Repeat three times when you feel stressed.

Tip: Try this before meals to signal to your body that it’s safe to enter rest and digest mode and improve digestion.

2. Humming, Chanting, or Singing

Your vocal cords are connected to branches of the vagus nerve, so humming, chanting “om,” or singing out loud creates soothing vibrations that activate it.
Try doing this for 30–60 seconds daily, or even while driving to an appointment.

3. The Basic Exercise

Adapted from Stanley Rosenberg’s Accessing the Healing Power of the Vagus Nerve, this gentle exercise helps the nervous system reset.
Lie on your back with your hands cradling your head. Keep your head still and look with your eyes up and to the right until you feel a yawn or sigh. Then repeat up and to the left.
Use it at night or after a stressful workday to shift into relaxation mode.

4. Gargling

Gargling engages the throat muscles connected to the vagus nerve. Try gargling water for 30–60 seconds every morning before brushing your teeth to gently stimulate vagal tone.

5. Eat Mindfully

Eating in a relaxed, aware state supports digestion and vagus nerve activation. Slow down and chew your food 20+ times, noticing flavor and texture. Even with coffee or tea, pause to savor the aroma and warmth; this helps your nervous system register safety before digestion begins.

6. Cold Exposure

Cold therapy is not just for athletes or longevity doctors - it’s also a natural form of vagus nerve stimulation. Start by splashing cold water on your face for 30 seconds in the morning or when you’re overwhelmed.
As your tolerance grows, try ending your shower with 30–60 seconds of cold water, or, if available, enjoy a short cold plunge. Cold exposure not only supports stress resilience but may also improve inflammation and mood.

7. Mindfulness Meditation

Ground yourself in the present moment with a simple sensory scan:

• 5 things you can see

• 4 things you can hear

• 3 things you can feel

• 2 things you can smell

• 1 thing you can taste

Or focus on your breath for 5–10 minutes. Mindfulness strengthens vagal tone and helps regulate both your nervous system and digestion. There are many free guided meditations online if you’re just starting out.

8. Legs Up the Wall Pose

Lie on your back with your hips near a wall and your legs resting up. Breathe deeply for 5–10 minutes. This gentle inversion relaxes the nervous system, improves circulation, and helps the body release stress - perfect before bedtime.

Bringing It All Together: Functional Nutrition and Nervous System Health

In functional nutrition, we view gut health and nervous system balance as deeply interconnected. Nutrients like omega-3 fatty acids, magnesium, and B-vitamins support healthy nerve signaling and help calm inflammation. Pairing targeted nutrition with daily vagus nerve exercises can improve digestion, reduce stress, and enhance overall well-being.

Each nervous system is unique, so try a few of these techniques and notice which help you feel most grounded and calm. Over time, you’ll strengthen your vagal tone, your body’s natural ability to recover from stress and return to balance.

When you care for your vagus nerve, you support the body’s natural ability to rest, digest, and heal - foundations of lasting wellness.

Curious to learn more? Make an appointment with our functional nutritionist, Nicole, to work on personalized lifestyle modifications and vagus nerve exercises.

References

• Ali, M. K., & Chen, J. D. Z. (2023). Roles of Heart Rate Variability in Assessing Autonomic Nervous System in Functional Gastrointestinal Disorders: A Systematic Review. Diagnostics (Basel, Switzerland), 13(2), 293. https://doi.org/10.3390/diagnostics13020293 

• Bonaz, B., Sinniger, V., & Pellissier, S. (2016). Vagal tone: effects on sensitivity, motility, and inflammation. Neurogastroenterology and motility, 28(4), 455–462. https://doi.org/10.1111/nmo.12817 

• Breit, S., Kupferberg, A., Rogler, G., & Hasler, G. (2018). Vagus Nerve as Modulator of the Brain-Gut Axis in Psychiatric and Inflammatory Disorders. Frontiers in psychiatry, 9, 44. https://doi.org/10.3389/fpsyt.2018.00044 

• Nowacka-Chmielewska, M., Grabowska, K., Grabowski, M., Meybohm, P., Burek, M., & Małecki, A. (2022). Running from Stress: Neurobiological Mechanisms of Exercise-Induced Stress Resilience. International journal of molecular sciences, 23(21), 13348. https://doi.org/10.3390/ijms232113348

• Rosenberg, S. (2017). Accessing the Healing Power of the Vagus Nerve. North Atlantic Books.