We recently spoke with Dr. Emeran Mayer, PhD, gastroenterologist, neuroscientist, professor and author of The Mind-Gut Connection, to pick his brain on the incredible ways that the gut and mind communicate. He focuses his research and career on “bringing the brain back into medicine.”
Dr. Mayer will be attending an upcoming event in Los Angeles with CYE founder Ilchi Lee to discuss the connection between the gut and brain. They will also address the influence Belly Button Healing has on strengthening this connection and improving the overall health of the body.
CYE: In your research over the last 35-years of your career, what has surprised you most about the relationship between the brain and the gut?
Dr. Mayer: I have always had a longstanding personal interest in the interactions between the mind and the digestive system, and have always been fascinated by the insights ancient healing traditions have had in these interactions for thousands of years. I have pursued this interest as a scientist and clinician for the past 35 years from different viewpoints.
In the beginning my main interest had been on the signals the brain sends to the digestive system. Later I became equally fascinated by the way the gut can send signals to the brain. The gut microbes became the latest and most surprising player in this communication. Not in my wildest dreams would I have believed that microbes living in our intestinal tract have anything to do with the brain gut axis, our emotional state and our health.
Today, I see the brain gut microbiome interaction as a circular, integrated process of signals going in both directions all the time, with the microbes being an active player in this communication.
CYE: In your TEDx talk you mentioned the gut contains wisdom and transmits this wisdom to the brain. Where does this wisdom come from and why does it live in the gut?
Dr. Mayer: The gut and its own (enteric) nervous system is much older than our brain. The most primitive marine animals, like the hydra, lived some 500 million years ago in the Earth’s ocean. They were basically floating digestive tracts which were wrapped into a network of nerves that regulated digestive function.
These marine animals started to interact with microbes and algae living in the oceans which decided that it was beneficial for them to live inside these primitive animals. These microbes had several hundred times more genes than their hosts (which they had accumulated over 3.5 billion years), and started transferring some of this information to the nerves of the marine animals, which ultimately turned into our neurotransmitters and was a prerequisite for the development of our nervous system.
So our gut and its microbes have an ancient history, and have evolved for billions of years accumulating a lot of wisdom about communication along the way.
CYE: In your book, The Mind-Gut Connection you state the microbes actually “speak” to the brain. How does this communication happen and how does this influence our emotional and mental states?
Dr. Mayer: There are multiple communication channels between the gut and the brain: immune mechanisms, hormonal mechanisms and neural mechanisms. The microbes living inside of our gut, and talking to the gut, are able to take advantage of these existing gut brain communication channels to send their own signals to the brain.
As food intake is one of the major factors influencing gut microbial composition and behavior, what we eat has therefore a way to influence our emotional brain centers and this effect is mediated by the gut microbes. The microbes digest some of the food we eat, produce signaling molecules which then communicate through the above channels with the brain.
The fact that many of the microbes’ signaling molecules are very similar to our own neurotransmitters allows for a amazing bidirectional dialogue between the microbes in the gut, and our emotional centers in the brain.
CYE: How much does diet affect mental health in terms of depression?
Dr. Mayer: This is a great question, but unfortunately, I don't have a scientific answer for it. There are many neuroactive substances in food (including serotonin in chocolate), and the gut bacteria are able to produce many neuroactive substances from the fermentation of food.
Based on what we currently know about gut microbes, certain strains are able to influence the synthesis of serotonin in the gut, which then can signal via the vagus nerve into the emotional centers of the brain.
We also know that high fat and high sugar diets can have a beneficial effect on mood (“comfort foods”), but the effect is transient, and in the long term such diets have negative effect on mood and brain health. My personal opinion is that by eating a healthy diet (high in plant based foods) together with a healthy lifestyle (regular exercise and meditative practices) has a major beneficial effect on mental health.
CYE: Belly Button Healing may be a new concept for the western world, but the acupressure and acupuncture point at the navel has been used for healing across cultures for thousands of years. How do you think the stimulation of this point will affect the communication between the gut and brain and how can it improve our health, both mental and physical?
Dr. Mayer: I had not heard about the belly button stimulation technique until very recently, and have not read any scientific reports on its effect on health. However, I can imagine that stimulation of the navel will have an effect on blood flow and on vagal nerve endings in the gut, which then send a signal to the brain. I am anxious to learn more about the technique.
CYE: When you first heard of Belly Button Healing, what was your initial reaction? Were you skeptical, or did you think of it as an excellent physical exercise to compliment with proper diet and mindful attention to our gut?
Dr. Mayer: I was surprised the first time I heard about it, and as a scientist I am a skeptic by nature. But I can think of several ways by which this type of stimulation has a beneficial effect on the brain gut axis. Such possible mechanisms include stimulating blood flow to the digestive tract, and activating nerve endings that may communicate with the enteric nervous system and the brain. Another mechanism which may play a role is the shift of attention to the belly. I am anxious to learn more about this technique.
About the event
“Healthy Gut & Happy Brain Workshop” is open for all to attend. Seats are limited. Click here to learn more and get your tickets.