Mindful Eating: Tips to Keep Your 'Second Brain' Healthy

Mindful Eating: Tips to Keep Your 'Second Brain' Healthy - A TCM physician recommends the best way to eat to improve gut health.

Mindful Eating: Tips to Keep Your 'Second Brain' Healthy

Mindful Eating: Tips to Keep Your 'Second Brain' Healthy


Health Viewpoints
There are between 200 million and 600 million neurons in the human gut. Some say the digestive tract is a human's second brain. Is this a fair statement?
Modern-day people face ever-increasing stress, which leads to various health problems. A recent survey of over 73,000 people in 24 countries found that over 40 percent were troubled by functional gastrointestinal disorders (or disorders of gut-brain interaction), including irritable bowel syndrome. The prevalence rate was particularly high among women.
A complex bidirectional communication link exists between the brain and the gastrointestinal tract. Studies have found that the intestine is the largest endocrine organ in the human body, secreting a few tens of signaling molecule types. Peptides secreted by the gut can bind to immune cells and receptors on the vagus nerve to transmit information, affecting the mental health of humans and animals alike. Inversely, when creatures experience anxiety or depression, intestinal function is also affected, triggering changes in intestinal microbiota and even leading to leaky gut syndrome.

Is the Gut Really a Second Brain?

An article published in Science in 2019 introduced that gut microbes determine whether the central nervous system and the social behavior of animals can develop normally. One study found that mice raised under sterile conditions without microbes in their guts had abnormal brains and social impairments. When researchers implanted microbes in the guts of the mice, their brain function recovered, and they started socializing with their own species. However, they could not recognize familiar mice because the lack of gut bacteria at a younger age meant they missed opportunities for brain development.

You may have heard the gastrointestinal tract referred to as the "second brain." The digestive system and the brain do have many similarities but also many differences. The brain has cognitive functions, learning and memory, advanced neural activities, and emotional regulatory functions, which are not available in the digestive tract, so it is not exactly true to say that the gut is a "second brain."

However, the digestive tract and the brain also share some similarities. The digestive tract has a vibrant and independent nervous system, with hundreds of millions of nerve cells, all transmitting signals through neurotransmitters. These neurotransmitters include serotonin, dopamine, and ethercholine, all of which play essential roles in the brain and digestive tract.

The 2 Nervous Systems

There are two nervous systems in the digestive tract: The local gastrointestinal nervous system and the sympathetic and parasympathetic nerves (also called the vagus nerve). The parasympathetic nerves are connected to the brain and control digestion and absorption of the gastrointestinal tract, secretion of gastric juice, intestinal hormone secretion and immune function, etc. The brain can affect the function of the digestive tract by regulating the sympathetic and parasympathetic nervous systems, and the digestive tract can also affect our thinking, mood, and behavior by sending signals to the brain.

How do the sympathetic and parasympathetic nervous systems affect the function of our digestive tract? The sympathetic nerve is the nervous system that is excited when we are in a state of fight or flight during an emergency. It will make our digestive tract reduce blood supply, stop secreting digestive juice, weaken peristalsis, etc., to transfer more blood and energy to other parts of the body to deal with danger. The parasympathetic nerve is the nervous system that is excited when we are in a state of relaxation. It will increase the blood supply to our digestive tract, secrete abundant digestive juices, strengthen peristalsis, etc., to activate digestion and absorb nutrients from food.

Therefore, to preserve good digestive functionality, we must relax when eating so that our parasympathetic nerves are excited and the sympathetic nerves are at rest.

Rest and Digest

The ancient Chinese used to say: "Don't talk while you eat; don't talk while you sleep." This motto comes from "The Analects of Confucius," which tells us something about the behavior of Confucius himself, and that he was very attentive while eating and sleeping and refrained from talking on both occasions. On the contrary, modern people often chat when eating, scan their mobile phones, or watch TV. Worse is when people watch nerve-wracking or scary things while eating, which excites the sympathetic nerves, preventing the secretion of digestive juices, stopping peristalsis, reducing the blood supply of the digestive tract, and causing various gastrointestinal problems.
Research has found that concentrating on eating at mealtime can lower cortisol (the stress hormone) levels. A randomized controlled clinical trial divided 47 overweight or obese women into two groups. The experimental group received meditation training and ate bento boxes together to practice the skill of mindful eating. Those in the experimental group had lower cortisol levels than those in the intervention or waitlist group. Since cortisol is associated with central obesity, focusing on eating can also help obese people manage their weight, reducing belly fat especially.

Doing just one thing right can significantly improve our gastrointestinal function and help prevent stomach diseases. Relax during mealtime and focus on mindful eating!