The body's immune system typically protects itself from disease, yet an abnormal response can harm and even destroy the body it's trying to protect. Dr. Oz talks to neurosurgeon Dr. Kevin Tracey, a leading researcher in the developing field of neuroimmunology, about how the brain functions in regulating the immune system.
In some situations, Dr. Tracey says that the immune system—by responding to some health threat, be it an injury, a burn or an infection—actually produces "weapons" that cause disease.
Through his research, Dr. Tracey discovered an overproduction of one molecule in particular produced by the immune system called TNF. He says that if you produce a normal amount of TNF, this molecule is very important to maintaining health. But after certain types of injuries, an overproduction of TNF can have disastrous consequences.
In an effort to determine how the immune system is normally regulated so that it doesn't overproduce these lethal molecular weapons, Dr. Tracey says his research led him to the discovery of something termed the "inflammatory reflex."
Dr. Tracey discovered that the brain, which normally controls virtually all the components of day-to-day living—your heart rate, your respiratory rate and all of your normal organ functions—also controls the immune system.
Moreover, he says brain signals that are carried down what's been called the most important nerve in the body, the vagus nerve, serve as a break to prevent the release of TNF and other molecules by the immune system. "That's one important mechanism for which the brain can provide the oversight, the control [and] the regulation to prevent damage or disease generated by the immune system," Dr. Tracey says.