Definition

The vagus nerve is the longest cranial nerve, extending from the brainstem to the abdomen, controlling the parasympathetic ('rest-and-digest') nervous system. It regulates heart rate, digestion, immune response, inflammation, and mood. Vagal tone—the strength of vagus nerve activity—is a key marker of resilience and health.

Why It Matters

Low vagal tone is associated with chronic inflammation, poor digestion, anxiety, depression, and cardiovascular disease. Stimulating the vagus nerve through deep breathing, meditation, cold exposure, singing, and yoga activates the relaxation response, reduces inflammation, improves digestion, and enhances mental health.

Related Conditions

Anxiety Depression Ibs Inflammation Hypertension

Related Modalities

Lifestyle Medicine Clinical Nutrition Ayurveda

Frequently Asked Questions

Practices that stimulate the vagus nerve include deep, slow breathing, meditation, yoga, singing or humming, cold exposure (cold showers, ice on face), gargling, laughter, social connection, and omega-3 fatty acids. Consistent practice over weeks improves vagal tone and stress resilience.

Signs include difficulty relaxing, chronic digestive issues, poor heart rate variability, chronic inflammation, anxiety, depression, difficulty recovering from stress, and autonomic nervous system imbalances. Functional medicine practitioners can assess vagal tone through heart rate variability testing.