Your metabolism, temperature, heart action and digestion are all controlled by the two branches of the autonomic (automatic) nervous system: the sympathetic nervous system and the parasympathetic nervous system. The sympathetic nervous system manages your response to stress and danger; it increases adrenalin and your metabolic rate in what is commonly called the “fight or flight” response. Your body prepares for danger with an increased heart rate, dilation of the lungs to maximize air intake and an increase in glucose metabolism to assure the brain and muscles have adequate fuel. The parasympathetic nervous system, on the other hand, works in an opposite manner. It is often referred to as the “rest, digest and heal” part of the nervous system.
Ideally, these two systems are balanced, and the body moves quickly and efficiently from one to the other and back based on the needs of the moment. When you are in a life-threatening situation survival is more important than digesting and healing. However, when the danger is past you should move back into parasympathetic rest, digest and heal. In sympathetic dominance, an overactive sympathetic nervous system can keep you in a constant “fight or flight” state and cause high blood pressure, heart failure and major depression.
The following PubMed studies show that chiropractic adjustments reduce sympathetic dominance and help your body move more efficiently between the sympathetic fight or flight response and the parasympathetic rest, digest and heal state:
*Journal of Spine Jan. 1997
*Journal of Clinical Neurophysiology 2007
*Autonomic Neuroscience 2001
*Journal of American Osteopathic Assn Dec1979
*Alternative Therapeutic Health Medicine 2011
*Journal of Human Hypertension 2007