Name: The Mind-Gut Connection
Rating: 4.5 (524 reviews)
Author: Emeran Mayer

What’s in it for me? Manage your emotions differently by understanding how your gut affects everything

Have you ever wondered why your stomach churns when you're nervous or why a hearty meal can bring you comfort after a tough day? It all comes down to the astounding relationship between your gut and your brain.

Just imagine: nestled within your gut are trillions of microscopic organisms, all bustling with life – and they're not just helping you digest food. They're chatting with your brain, influencing your mood, thoughts, and feelings. But, as it turns out, the conversation is two-way. Yes, your brain has something to say, too!

In the following Blink, you'll discover how your diet, stress levels, and even your social connections can affect this bustling micro-world within you. And you’ll get an idea of how to improve and even repair your brain-gut communications so you can enjoy better all-around well-being.

So, strap in and get ready to change the way you view your gut, your brain, and perhaps your health overall.

Royal enemas, etc.

The earliest writings of ancient humankind contain references to enemas. In Ancient Egypt, the pharaoh had a “keeper of the rectum” who managed all of his enemas. Ancient Babylonian and Assyrian tablets mention the use of enemas as early as 600 BC. Susrut, the father of Indian surgery, wrote details of implements he used to clean out the colon.

Why has humanity been obsessed with the state of the human gut for so long? The answer may lie in a quote credited to Hippocrates: “All disease begins in the gut.”

It turns out that Hippocrates wasn’t too far off in his thinking. We now know that immune cells located throughout the gut make up the largest part of the immune system. Not only that – the gut is equipped with its own dedicated nervous system that many people refer to as a second brain. And, as if that weren’t enough, the gut contains endocrine cells that hold 20 kinds of hormones and also contains the largest supply of serotonin in your body.

These systems don’t just hang out in the gut independently of the rest of the body. They communicate with the brain via the vagus nerve. So if you’ve ever had a “gut feeling” about something, that phrase is more than just a metaphor. You probably had a literal gut feeling.

Using this vagus nerve super highway, your brain receives tons of information from your gut every day, and stores that information in memories. Studies suggest that you’ll never be consciously aware of about 90 percent of that information, but it can and does affect how you behave in response to certain stimuli. Research has also found that 90 percent of the information transferred goes from gut to brain, and only ten percent from brain to gut. Think of the gut like an agent in the field sending intelligence back to head office.

So with all of this information at hand, it’s no wonder that researchers are speculating about the possibility of the gut’s role in the development of mental and emotional conditions like depression and anxiety.

In 1822, army surgeon Dr. William Beaumont was able to witness firsthand, in a bizarre way, the direct effect that emotions have on digestion. He treated a man named Alexis St. Martin, who had been accidentally shot through the stomach with a musket.

While Dr. Beaumont was able to help St. Martin regain function, he wasn’t able to permanently close up his stomach. As a result, there remained enough access to the stomach so that Dr. Beaumont could actually observe digestion in real time. With the consent of St. Martin, Dr. Beaumont studied the direct effects of emotional stimuli on digestive responses.

As the experiments were often uncomfortable for St. Martin, he frequently became upset during the process. By watching St. Martin’s gastric activity as his mood turned, Dr. Beaumont found that St. Martin’s anger ended up slowing his digestion.

While Beaumont’s experiments showed how feelings affect digestion, later experiments showed how gut microbes affect behaviors. Scientists transplanted fecal microbes from one mouse into another and observed any changes in behavior. They found that a timid mouse injected with the microbes of an extroverted mouse became more extroverted. And a lean mouse injected with the microbes of an obese mouse changed its eating habits and gained weight.

This opens up a whole realm of speculation on the role gut microbes play in your feelings and behaviors, and what possibilities there may be in the future for gut-based therapies.

Funny feelings in your gut

In 1983, a Soviet Air Defense Forces officer named Stanislav Petrov received a system alert that five missiles were heading toward the Soviet Union from the United States. Faced with the potential of an all-out nuclear war, Petrov opted not to take any action.

Of course, as it turned out, the warning was a false alarm, but Petrov didn’t truly know that at the time. When asked why he didn’t alert someone or launch retaliatory missiles, the officer gave several reasons, but during a later interview, he explained that he simply had a gut feeling.

Get superhealthy

Only five percent of the North American population qualifies as superhealthy, meaning they are living in a state of optimal health in all areas of life, including physically, emotionally, spiritually, and more.

When you learn how the odds are stacked against you, it’s not surprising that the number is so low.

Final Summary

A human being functions more like an ecosystem than a machine. The more we learn about that ecosystem and the trillions of microbes living within it, the more we realize how important diet is to literally everything about life – from our physical health, to our emotional responses, to the way we behave in different situations.

And it’s a two-way street. Emotions can affect digestion, too. The organisms living in the gut communicate directly with the brain via a complex nerve system known as the “second brain.” Knowing this, we can now begin to understand how we are what we eat and how our emotions are shaped by the microbial response to stimuli within our gut. And finally, we’ve learned that the dietary wisdom we know so well, such as the advice to avoid processed foods and eat at the family table, are actually vital to our health.

What is The Mind-Gut Connection about?

The Mind-Gut Connection (2016) explores the complex relationship between the gut and brain, highlighting the crucial role this connection plays in both physical and mental health. The book delves into key insights, such as the brain-gut axis, the impact of stress on gut health, and the connection between food and mental well-being, emphasizing the need for holistic care to improve overall health.

About the Author

Emeran A. Mayer, MD is the author of The Mind-Gut Connection and The Gut-Immune Connection. His books are informed by 40 years of studying mind-brain-body connections. He is the executive director of the Oppenheimer Center for Neurobiology of Stress and Resilience and the Co-director of the CURE: Digestive Diseases Research Center.