Healthy Stomach Bacteria and the Neuroimmune System – Part 1

By: Michael Lam, MD, MPH; Justin Lam, ABAAHP, FMNM

for proper digestion one must have healthy stomach bacteriaHealthy stomach bacteria– not many people think about these organisms in a positive way. Most think right away of something that invades your body and makes you sick. Immediately, the majority of people get a picture of bacteria causing stomach aches, nausea, and vomiting. Something to be killed by antibiotics. The truth is, healthy stomach bacteria actually keeps you healthy and slows down the aging process.

Bacteria gets into your body from whatever you eat or put in your mouth. And this process starts literally at birth. During the trek from womb to physical birth, you travel through the birth canal and pick up many of your initial stomach bacteria from your mother. You get both harmful and healthy stomach bacteria on this trip.
The more researchers study the bacteria in your stomach, the more the evidence stacks up that your stomach bacteria, along with the bacteria that populate your gut microbiota, strongly affect how you feel both physically and emotionally.

One of the ways bacteria in your stomach affect you physically is the connection between your gastrointestinal (GI) system and your immune system. Researchers suggest a great deal of your immune system is in your gut system. Others say up to 90 percent of diseases originate in your gut. This makes healthy stomach bacteria even more important.

Not only are healthy stomach bacteria vital in keeping you well, they also help you deal with illness conditions. This article will discuss both of these factors.

A human body contains over 10,000 microbes — or more than ten times the number of human cells! The genome of the microbiome, as an entity, is 100 times larger than the human genome, implying that the majority of genetic material inside your body is not actually yours, but the microbes’. These microbes include viruses, fungi, and bacteria that use the body as a habitat to form a balanced ecosystem. This ecosystem is called the microbiome, which is found in and on the bodies of humans and living things—in the mouth, on the skin, inside the gut. The human microbiome includes both harmful and beneficial organisms. The balance is shifting constantly and can affect the human host’s health. For the most part, the bacteria found in your body are valuable to your health and well-being and play a vital role in your survival. These bacteria are not only depended on for survival, they assist in the daily functions of digestion, vitamin creation, and protection against infections, as well as in a plethora of other roles. This article primarily deals with the gut flora, those microorganisms that live in the digestive tract.

Adrenal Fatigue Syndrome (AFS)

AFS is a significant health condition that occurs when your adrenal glands, located on the tops of your kidneys, become depleted and unable to secrete cortisol, the hormone that helps your body handle the effects of stress. This health condition comes when stress attacks your body.

healthy stomach bacteria and obesityRegardless of the origin of the stress, your body reacts the same way. An automatic response pathway is set in motion, beginning with the hypothalamic-pituitary-adrenal (HPA) axis. Various hormones and other chemicals begin the cascade of responses that end with your adrenals secreting cortisol to fight the effects of stress. Unfortunately, in this stress-filled world we inhabit, stress continues, overwhelming your system as your adrenals are depleted.

AFS presents with a long list of physical and emotional symptoms, including insomnia, weight gain around your middle, lack of energy, inability to think clearly, feeling tired even after a good night’s sleep, depression, and poor memory. These symptoms and a lot of serious physical conditions can be triggered by stress resulting from not so healthy stomach bacteria and the changes they can bring due to inflammation and suppression of your immune system.

Because of the multitude of symptoms and their sometimes vague nature, physicians can have a difficult time making an accurate assessment of your condition. This leads to potentially ineffective remediation of your illness.

The NEM Stress Response

One reason physicians may have such trouble determining the root cause of your illness is due to their way of viewing the expression and remediation of disease. Most traditionally trained physicians look at your presentation of symptoms from an organ-specific viewpoint. This limits their choice of ways to handle your illness. In addition, many physicians are specialists and their outlook is limited to their specialty area.

The NeuroEndoMetabolic (NEM) stress response is the body’s system of dealing with stress. There are six major components or circuits, each comprised of various organs and systems programmed to act on specific, targeted anti-stress responses. These components work synergistically to ensure that your body is well taken care of in the face of stressful situations. With regard to your stomach bacteria, the metabolic, immune, and hormone systems are the first to be affected. As your body reacts to the stress of unhealthy bacteria and their effects on inflammation, the other systems also begin to suffer. The neuroaffective and inflammatory responses are two circuits within NEM stress response that significantly alter mood, immune function, and cognition. These circuits involve three intricately interconnected components—the gut, brain, and microbiome—forming what is called the gut-brain axis. What happens to one component will affect the others. The neuroaffective circuit is made up of the autonomic nervous system, central nervous system, and gut. The inflammatory response circuit is composed of the gut, microbiome, and immune system. As you can see, the gut and its microbes are important to both circuits and link the two. Your body’s reaction to stress can lead to increased inflammation, just as an unhealthy gut biome will. Researchers have shown inflammation to be a factor in illness conditions as varied as depression, Parkinson’s disease, Alzheimer’s disease, and even autism. In order to most successfully deal with the symptoms of AFS and any symptoms of unhealthy stomach bacteria, your health professional should consider how all systems of your body interact as in the NEM model. The brain and gut seem so different and so far apart, so how does the connection work? Let’s take a look.

The Gut-Brain Axis

healthy stomach bacteria and the gut brain axisGut flora influence various brain functions, affecting your thoughts, emotions, and memory. Three quarters of the body’s neurotransmitters are actually made in the gut. That is why the signals that go between the brain and the gastrointestinal (GI) tract are vital to establishing and maintaining homeostasis, immune health, and hormonal levels. This connection is regulated by the central nervous system and the enteric nervous system. When there is a disturbance in either of these systems, it affects your ability to respond to stress and influences your overall behavior. As can be seen in those with inflammatory bowel disorder (IBD) and irritable bowel disorder (IBS), there is a strong correlation between anxiety and gastrointestinal disorders that demonstrates the significance of the connection axis between the brain and GI tract.

There is also mounting evidence suggesting that the enteric microbiome (in the intestines) affects gut-brain communication, hence the naming of the microbiome-gut-brain axis.

An unbalanced collection of gut flora (dysbiosis), combined with stress, could lead to damage the gastrointestinal lining and increase the permeability of the blood-brain barrier. Thus, an unbalanced population of gut flora and healthy stomach bacteria can contribute to the inflammation of the whole body in addition to affecting the neuron signaling from the gut to the brain.

How Microbiome Affects the Human Brain

There is a wealth of evidence that demonstrates complex interactions between host and microbe. There are three particularly important methods by which the microbes in your gut interact with the brain: directly, via the vagus nerve and a network of nerves that wrap around the gut and transfer signals to the brain; through the circulation of primed immune cells that exist in the gut and move towards the brain; and through metabolite molecules, produced by gut microbes, that enter first the bloodstream and then the brain and eventually affect behavior. These metabolites have been shown to cause abnormalities associated with anxiety and autism when injected into healthy functioning mice. This could lend further support to the possibility of microbial molecules connecting the brain, gut, and neuroaffective circuit of the NEM stress response system.

Communication Between Your Two Brains

That there is a complex interconnectedness among your gut system, your brain, and your immune system has been shown through research over and over. However, how they are interconnected and how they communicate is not as clear.

A tremendous amount of research has taken place recently providing information about how healthy stomach bacteria (that are a part of your gut microbiome) are crucial not only to your immune system, but also to the way your genetic makeup is expressed, to body health, to memory, to mental health, and to making you less susceptible to serious illness like cancer.

Some of this research has explored how communication happens between your two brains, the one in your head and the one in your enteric nervous system (ENS) that is embedded in the wall of your gut. This ENS is the part of you gives you that “gut feeling” when something is about to happen or isn’t right. It developed as the original nervous system in our distant ancestors and is made up of 500 million neurons. Scientists suggest it has so many because food can be dangerous.

How the mind is effected by healthy stomach bacteriaThere is some research evidence that suggests your enteric nervous system and your brain develop from the same embryonic tissue.

With the gut’s job of keeping out foreign “invaders” in the form of bacteria, there must be plenty of neurons to determine good from bad foods. In the case of ingesting bad food, this ENS signals your other brain to induce either diarrhea or vomiting to rid the body of the bad food.

How does it do this? About 90 percent of the communication between your gut brain and your head brain goes along the vagus nerve. Since vagus is Latin for wandering, this is a nerve that literally wanders through your body connecting many organs. The communication between your two brains is bidirectional. Information flows both ways between your brains.

This communication travels in the form of cytokines produced in your gut. They are intimately involved in cell communication having to do with immune functioning and inflammation. They are like hormones and serve the function of signaling cells where to go when an inflammatory response occurs.

Cytokines may travel from your gut to your brain and stimulate microglia, the immune cells in the brain, to produce neurochemicals. Some of these neurochemicals affect your mitochondria in a negative way, decreasing energy production and impacting the feedback loop that controls hormones, including cortisol.

This is just one way the unhealthy and healthy stomach bacteria in your gut system have far-reaching effects. They affect and have significant control over your entire bodily health.

The vagus nerve communication appears to be so important that researchers have found stimulation of this nerve to have a calming effect on the autonomic nervous system. When the vagus nerve is surgically cut (a vagotomy), the opposite effect occurs. When the vagus nerve is intact, it works to reduce inflammation and restore homeostasis.

Some research suggests pathogens can travel along the vagal pathway as well and, over a period of time, may give rise to an increased risk of Parkinson’s disease. On the other hand, full truncal vagotomy appears to decrease this risk. This finding highlights the importance of this vagal communication pathway between your ENS and your brain.

Healthy Stomach Bacteria and Stress

A significant number of researchers have found stress to have a strong effect on your health. The activation of the HPA axis begins a cascade of responses to stress that clearly have an impact in your stomach and gut.

Scientists are convinced your gut bacteria are continually influenced by lifestyle choices, diet, and environment. It’s nearly impossible today to stay away from stressors in the environment. Some of these stress producers come from choices you make, some come from toxins in the environment, and some are the result of poor diets filled with fast foods.

healthy stomach bacteria and stressStress from any source can lead to increased inflammation and decreased immune functioning. Inflammation wreaks havoc on your healthy stomach bacteria and your gut system. When your gut is thrown out of balance (dysbiosis), your body is opened up to all kinds of illness conditions.

With increased inflammation, the healthy stomach bacteria begin dying off from increased toxins in your system and those that aren’t as healthy seem to thrive. This can lead to a condition known as “leaky gut” where those toxins actually penetrate your gut lining and travel throughout your body.

Not only do these toxins prime your body for significant health problems, your stomach and gut are no longer able to extract sufficient nutrients from the food you eat to energize your body. These systems and the bacteria that live there also contribute to fat storage. When the balance of bacteria in your stomach and gut is disturbed, changes in body fat can also take place.

One study showed germ-free mice to gain weight and increase fat storage without increasing food intake when injected with gut bacteria from overweight mice. Apparently, the receiving mice’s gut system stimulated the production of hormones like insulin and increased fat storage, leading them to gain significant weight. The apparent stress of getting “foreign” bacteria led to this weight gain.

Read Part 2 | Part 3 | Part 4

© Copyright 2017 Michael Lam, M.D. All Rights Reserved.

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