How Does the Vagus Nerve Tamp Down Inflammation?

One crucial function of the vagus nerve is to dial down inflammation in the body. This occurs through the cholinergic anti-inflammatory pathway, explains functional-medicine physician Gregory Plotnikoff, MD.

When the vagus is stimulated, it sends electrical signals along its length. These lead to the release of acetylcholine, a neurotransmitter that regulates inflammation.

Acetylcholine interacts with specific receptors on immune cells, inhibiting the production of proinflammatory proteins called cytokines. Reducing proinflammatory cytokine production can lower inflammation not just locally but throughout the body. When we’re in fight-or-flight mode, the vagus nerve isn’t being stimulated, so it can’t send these important inflammation-reducing signals.

“This pathway is the functional ­relay circuit between the nervous ­system and the immune system — the neuroimmune system,” says functional-medicine provider Navaz Habib, DC. This relay plays a key role in conditions characterized by widespread inflammation, such as rheumatoid ­arthritis or inflammatory bowel diseases (IBD). It’s why stress is linked with higher inflammation and worse symptoms in so many conditions.

It’s also why VNS is so promising for any condition worsened by stress in which inflammation plays a role.