20 Ways Deep Breathing Reduces Cortisol Instantly

12. The Vagus Nerve: Your Internal Calm Button

Deep breathing is a direct activator of the vagus nerve, the longest nerve in the autonomic nervous system, often called the "wandering nerve." This nerve plays a critical role in regulating internal organ functions, including heart rate, digestion, and the immune system. By stimulating the vagus nerve, deep breathing directly communicates with your brain to dampen the stress response and promote relaxation, a powerful physiological "calm button" that reduces cortisol release and fosters a profound sense of tranquility.