Dr.Tanaka's "Eyes on Health" vol.2

Microorganisms even control our feelings!?

Is H. pylori really the bad guy?

In Japan, H. pylori (Helicobacter pylori) is considered as a major cause of gastric cancer, and it is recommended nationwide to remove it. However, in other countries, it is now known that H. pylori are symbiotic with people. It can be said that H. pylori, which reside in 80% of Japanese people’s stomachs, is no longer considered as pathogenic bacteria like cholera or Vibrio parahaemolyticus, but rather, indigenous bacteria.

In addition, the success rate of H. pylori removal is declining every year, and 20% of those who successfully removed H. pylori get infected again. A TV program once showed a patient who had to visit hospital 12 times for bacteria removal. Do we really need to do that much to remove H. pylori? It is worth keeping in mind that antibacterial products destroy your gut flora and that chemical products are often burdened to human bodies. Due to eradication, drug-resistant H. Pylori already came into existence. Is it really beneficial to create a vicious spiral of eliminating bacteria and letting new drug-resistant bacteria emerge? You could also think this way; your lifestyle is the real cause to disturb H. pylori’s environment. As a matter of fact, it will take more than a few decades from now to find out whether or not eliminating bacteria did decrease gastric cancer patients.


Symbiotic bacteria influence our mind!?

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In this article, I will focus on the relationship between microbes and our mind. Studies are finding out that microbes influence our metabolism a lot more than we imagined. For example, it is now known that H. Pylori can influence your gastric-acid secretion and even control your appetite. Your gut flora is deeply related to producing Serotonin, also known as ‘happy hormone.’


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Our feelings and moods are indeed controlled by substances produced in our brains. Angry people are often described as “having too much adrenaline.” Adrenaline is closely related to anger, sadness and anxiety. Dopamine pertains to pleasure, but if you pursue pleasure too much you will get addicted to it. Serotonin adjusts the amount of dopamine and pacifies your mind. This serotonin is produced synergistically by gut bacteria. I often hear, “If the mothers are living lives filled with beneficial bacteria, their babies are easier to raise because they don’t cry too much.” or “kids living EM lives seldom lose their temper, and they are so calm.” These things are convincing if you think that these kids have stable gut flora, producing plenty of serotonin.

Research on bacteria and mind

English 3It is being researched all over the world how our mind can be affected when beneficial bacteria are dominant in gut flora. A research in France shows that symptoms of depression decrease remarkably when gut flora is improved. There also is a research in the United States shows that people’s brains are not active and do not react to emotional stimuli (in other words, their waves of emotions are calm) when they are relaxed. From these research results, we could think that gut flora is related to serotonin.

Two dermatologists, Dr. Storks and Dr. Pillsbury, did many types of research on the relationships between “gut, brain and skin,” and discovered that inoculating lactic acid bacteria eases mice’s skin inflammation caused by stress and their fur grows back. It is often heard that stress causes skin problems and make atopic dermatitis worse, but now it is clear that our skin is also influenced by gut flora.

Studies in Japan are also finding out that bacteria-free mice get stressed out more easily than regular mice, gut bacteria affects cranial nerve development which is related to memories and learning, and etc. So, improving gut flora might make you smarter!

I am not sure to what degree, but it could be said that our biological activities as human beings are influenced by the numerous microbes living on our skin and in our guts. Now, don’t you want to cherish microbes even more? Microbes, the largest number of all living creatures on earth, have been here for a few billion years. There still must be many more relationships beyond our knowledge between microbes and us.

Relationships between nervousness, constipation, symbiotic bacteria and happy hormones

English 4By the way, many of us wonder why browsing books at bookstores often give us the urge to go to the bathroom. When you go out, you are tense because your sympathetic nerves are tense (sympathicotonia) in the autonomic nervous system. Under this condition, you are in the fighting mode, to confront your enemies. In this mode, your gut stops to move. However, it is switched to the relax mode once you are in bookstores. Then, the parasympathetic nerves, the relaxing nerves, become dominant, and the intestinal peristalsis starts again. When your gut moves, stool near the anus moves towards the anus. When the rectal pressure becomes higher, your brain gives an order, “let the poop out!!!” and it is more than natural to have a bowel movement. Thus, it can be said that it is easier to get constipated if you are continuously living a life full of stress. Being constipated, feces tend to rot, and bad bacteria dominate in the gut. Then, happy hormones decrease, and together with the stress, you will be short-tempered. Doesn’t that make a lot of sense?

Further, chronic stress and deterioration of gut flora may trigger a condition called irritable bowel syndrome or IBS, in which diarrhea and constipation come in turns. It also happens when you are under a lot of pressure for exams or feeling excessive stress upon public speaking. This condition may be caused when your current condition and the instruction from your brain don’t agree, such as, your brain doesn’t give an order to move intestine when the stool needs to go out. Things like, not letting it out when you need to, or taking a laxative because it doesn’t come out, will also cause this condition. Let us cherish the gut bacteria and aim for better bowel movements to achieve the peace of mind.


MD. Yoshimi Tanaka (Japan)

Graduated from the medical department of Tokai University in 1985. After working in neurosurgery at the same university hospital, he engaged in acute care in various hospitals in the city of Isehara, Kanagawa Prefecture for many years. Then, he obtained MD with the research on malignant brain tumors. Medical specialist for The Japan Neurosurgical Society and Japanese Society of Anti-Aging Medicine. Today, he is dedicated to promote preventive medicine, educational seminars, and writing books.