Skip to main content

Natural Awakenings Northwest Florida

A Curious Connection Between Our Two 'Brains’

Jun 02, 2013 04:11PM ● By Diane Vchulek

Many physical and psychological issues are processed through the stomach and gut? “Butterflies”, tightness and nausea are familiar sensations when experiencing feelings of fear, excitement, stress and anxiety. Underlying them is an extensive network of neurons lining the gut, known as the “second brain”. Michael Gershon, an expert in neurogastroenterology at New York Presbyterian Hospital, believes the second brain connects with the brain in our skull, working together to determine our mental and physiological states.

The nerves in our gut influence a large part of our emotions, through the vagus nerve. According to studies published in the Journal of Clinical Investigation, our butterflies are signaling stress as the processes of the fight-or-flight response take effect.

Studies using rodents have indicated that microbiome (microbes and their genomes) in the gut influences neural development, brain chemistry and a wide range of behavioral issues, including emotional behavior, pain perception and stress response. Research is showing that maintaining a balance between beneficial and disease-causing bacteria in the gut can even alter brain chemistry. Also, knowing that the brain can exert a powerful influence on gut bacteria, even mild stress can cause imbalance in the gut, increasing vulnerability to infection, disease and negative feedback to the nervous system.

Neurotransmitters in the brain are also found in the gut, so medications affecting neurotransmitters, such as antidepressants, often cause nausea and other gastric issues as side effects. Serotonin, the feel-good neurotransmitter, in the second brain might even play a role in autism and osteoporosis. Part of its job is to protect the immune system, help us sense environmental threats and influence our responses. Serotonin is involved in preventing depression and regulating sleep and appetite. Close to 95 percent of serotonin is present in the gut, not the brain.

According to Dr. Natasha Campbell-McBride, in her book, Gut and Psychology Syndrome, there are many connections between recovery from addiction and mental illness based on the gut, including the symptoms (depression, anxiety, phobias), sensitivity to what is being eaten, issues that mimic psychological components, commitment to abstinence, triggers and positive response to nutrition. Looking at the damage from alcohol and drug abuse, she indicates that widespread immune system damage, brain damage and weakened immune systems are creating a growing epidemic of mental and physiological problems that lead to behavioral abnormalities, poor mental development, mental illness, allergies and digestive diseases.

Individuals that suffer from addiction often have significant medical issues, including lung and cardiovascular disease, stroke, cancer and mental disorders. Especially vulnerable to damage from alcohol is the cerebral cortex, which is responsible for higher brain function and problem solving, and the hippocampus, responsible for memory and learning. Toxic inhalants damage the heart kidneys, lungs and brain. Cocaine is linked to heart and respiratory problems, as well as nerve and digestive system problems. All of these results are accompanied by severe mental health and psychological problems affecting all organs in the body, including the gut.

Depression, anxiety, addiction to drugs and alcohol may not seem to be likely associated with good intestinal and digestive health, but the brain and gut are connected, and better brain function is dependent upon good gut function. We are just learning about the intimate relationship between digestive health and mental health, but changes in how we treat diseases, including addiction, could be affected.

Diane Vchulek, MA, MS, LMHC, NCC, is the director of clinical services for Twelve Oaks Recovery Center, in Navarre. She holds an MS in counseling and human development, an MA in clinical psychology and is a licensed mental health counselor. Contact her at 850-939-1200 or

Global Brief
Health Brief