Your Gut, Your Second Brain

Have you ever had butterflies in your tummy before a big event? Or felt a queasy feeling in your stomach when things weren’t quite right? Or relied on your “gut instinct” when making an important decision? Why do we feel things emotionally in our gut? Scientists have learned that we have a second brain, called the enteric brain. It’s located in the gut and it affects your mood. Time to meet your gut, your second brain.

The Enteric Brain

The enteric nervous system (ENS) consists of more than 100 million nerve cells lining your gastrointestinal tract (this is more cells than your spinal cord has). Because of this vast number of nerve cells, we can “feel” what is happening inside us. The ENS communicates with your first brain in ways scientists are only beginning to understand.

According to Jay Pasricha, M.D., director of the Johns Hopkins Center for Neurogastroenterology (a newly emerging field), the enteric brain’s main role is “controlling digestion, from swallowing to the release of enzymes that break down food to the control of blood flow that helps with nutrient absorption to elimination. The enteric nervous system doesn’t seem capable of thought as we know it, but it communicates back and forth with our big brain—with profound results.”

Head Brain – Gut Brain Connection

For decades, doctors and scientists thought that depression and anxiety contributed to gastrointestinal problems like IBS (irritable bowel syndrome). Now, they are learning that the opposite is true.  Researchers are finding evidence that irritation in the gastrointestinal system may send signals to the central nervous system (CNS) that trigger mood changes. (1) It’s not all in your head, it’s in your gut!

Things that are happening in our gastrointestinal (digestive) systems, like leaky gut, will affect our central nervous system. Those feelings we talked about that we experience in our gut start in the gut and can affect our mental state, as well as whether we develop certain diseases.

Scientists have learned that around 90% of the fibers in the vagus nerve (the 10th cranial nerve which is part of the involuntary nervous system) carry information from the gut to the brain and not the other way around. 

According to Rosalyn M. King, Ed.D, “As light is shed on the circuitry between the two brains, researchers are beginning to understand why people act and feel the way they do. When the central brain encounters a frightening situation, it releases stress hormones that prepare the body to fight or flee. The stomach contains many sensory nerves that are stimulated by this chemical surge – hence the “butterflies.” On the battlefield, the higher brain tells the gut brain to shut down. Fear also causes the vagus nerve to “turn up the volume” on serotonin circuits in the gut. Thus over stimulated, the gut goes into higher gear and diarrhea results. Similarly, people sometimes “choke” with emotion. When nerves in the esophagus are highly stimulated, people have trouble swallowing. Even the so-called “Maalox moment” of advertising can be explained by the interaction of the two brains, according to Dr. Jackie D. Wood, chairman of the department of physiology at Ohio State University in Columbus, Ohio. Stress signals from the head’s brain can alter nerve function between the stomach and esophagus, resulting in heartburn. In cases of extreme stress, Dr. Wood said that the higher brain seems to protect the gut by sending signals to immunological mast cells in the plexus. The mast cells secrete histamine, prostaglandin and other agents that help produce inflammation. This is protective. By inflaming the gut, the brain is priming the gut for surveillance. If the barrier breaks then the gut is ready to do repairs. Unfortunately, the chemicals that get released also cause diarrhea and cramping.” (2)

You Are What You Eat

Our entire being is affected by what we eat (after all, “you are what you eat”). U.C.L.A.’s Emeran Mayer, M.D., Ph.D., is doing work on how the trillions of bacteria in the gut “communicate” with enteric nervous system cells. The head brain affects the gut brain as much as the gut brain affects the head brain.

Everything we consume becomes a part of our cells. If we eat real, whole food that the body recognizes, the body can pull nutrients from the food and use it to build, maintain, and support the body. If the body doesn’t recognize fake, junk food, the body will attempt to eliminate as much of it as possible. Whatever can’t be eliminated or assimilated is stored wherever the body can put it. In many cases, this leads to autoimmune disease.

Learn more in my new book, Be in Health: Bible-Based Health Restoration: Living in Harmony with God’s Ways Regarding Health. Available now.