It turns out that both our gut and our brain originate early in embryogenesis from the same clump of tissue which divides during fetal development. While one section turns into the central nervous system, another piece migrates to become the enteric nervous system. Later the two nervous systems connect via a cable called the vagus nerve -- the longest of all the cranial nerves whose name is derived from Latin, meaning "wandering." The vagus nerve meanders from the brain stem through the neck and finally ends up in the abdomen. There's the brain-gut connection.
Have you ever wondered why an impending job interview can cause an attack of intestinal cramps? And why do anti-depressants targeted for the brain cause nausea or abdominal upset in millions of people who take such drugs? The reason for these common experiences is because each of us literally has two brains --the familiar one encased in our skulls and a lesser-known but vitally important one found in the human gut. Like Siamese twins, the two brains are interconnected; when one gets upset, the other does, too. No wonder people trust their gut. One half of all our nerve cells are located within the gut?
The state of the gut has a profound influence upon our health. It is from the healthy gut that we enjoy neurological and psychological as well as immunological health. This is not to discount the human brain. This is simply to say that the body has two brains -- the second brain being our gut. There is an excellent article on this brain-gut connection called Complex and Hidden Brain in Gut Makes Bellyaches and Butterflies written by Sandra Blakeslee, originally published in the January 23, 1996 issue of The New York Times. I have added a link to her article in the Diet section of the Links page.
This complex circuitry provides the brain in the gut with the means to act independently. Proof of this can be seen in stroke victims whose brain stem cells, which control swallowing, have been destroyed. If this occurs, a surgeon has to create an opening in the abdominal wall, so that feeding can be accomplished by manually inserting foods directly into the stomach. Once the food is in the stomach, digestion and absorption can take place, even in individuals who are brain dead. The central nervous system is needed for swallowing and for defecation, but from the time the food is swallowed to the moment its remains are expelled from the anus, the gut is in charge.
Abnormal REM sleep is reduced by low-dose treatment with the anti-depressant amitryptiline, which has also been shown to be effective in treating lBS and non-ulcerative dyspepsia. Many drugs designed to affect the brain also affect the gut. For example, the gut is loaded with the neurotransmitter serotonin. In fact, more serotonin is produced there than anywhere else in the body. Serotonin is linked with initiation of peristalsis.
Although a little is beneficial for constipation, a lot is not. When the Gershon team greatly increased the amount of Prozac in the guinea pig colon, the pellet stopped moving at all. Hence, a little cures constipation; a lot causes it. Prozac stimulates sensory nerves, thus can also cause nausea.
The gut has opiate receptors much like the brain. "Not surprisingly, drugs like morphine and heroin that are thought to act on the central nervous system also attach to the gut's opiate receptors, producing constipation," notes pain management specialist Michael Loes, M.D., M.D.(H.), author of The Healing Response (Freedom Press 2002) "Both brains," he says, "can be addicted to opiates."
Many Alzheimer's and Parkinson's disease patients are constipated. A sickness we think of as primarily affecting the brain or central nervous system also impacts the gut.
Our gut also helps us in some amazing ways. The gut also produces chemicals called benzodiazepines. These are the same chemicals found in anti-anxiety drugs like Valium, and these are the same chemicals that alleviate pain. Perhaps our gut is truly our body's anxiety and pain reliever. While we are not sure whether the gut synthesizes benzodiazepine from chemicals in our foods, bacterial actions, or both, we know that in times of extreme pain, the gut goes into overdrive, delivering benzodiazepine to the brain. The result is to render the patient unconscious or at least reduce the pain, says Dr. Anthony Basile, a neurochemist in the Neuroscience Laboratory at the National Institutes of Health in
Lastly, in Biblical times, the seat of emotion, which we call the heart, is actually referring to the bowels. That thought in itself conjures up an image of a young Romeo sending a love note to his Juliet saying, "You move me."
In all seriousness, most people today completely ignore gut health. As a result, they are experiencing health problems that could be overcome if they knew that they centered in their gut. So I guess the thing to remember is, as Dr. Gershon puts it, "Take care of your gut and your gut will take care of you."