the gut microbiome as an endocrine organ


Gut Endocrine Organ

“Officially the endocrine system is made up of a network of glands that secrete hormones to regulate bodily functions, including growth and metabolism. These glands include the hypothalamus, pineal gland, pituitary gland, thyroid, ovaries, testes, and more.  We don’t usually count the human gastrointestinal tract as an endocrine organ, but with 30 trillion plus bacteria encompassing hundreds or thousands of bacterial taxa, and continually converting nutritional cues into hormone-like symbols that impact the human host, it’s fair to regard the gut as a command and control center in the body.  The microbiome is constantly making compounds, some of which are biologically active and act like hormones. They fulfill all the requirements of a hormone: a biologically active entity that diffuses in the bloodstream and act on a distant site.”  Debra Beck from one of last August’s articles in the American College of Cardiology’s journal (Fun with Flora, Does Our Microbial Ecosystem Drive Health and Disease?)

“The gut microbiota has recently been recognized as a key environmental factor driving metabolic diseases. In fact, the gut microbiota is even seen as a separate endocrine organ, which is involved, through a molecular crosstalk with the host, in the maintenance of host energy homeostasis and in the stimulation of host immunity. Shifts in gut microbial composition caused by external factors can result in a dramatic alteration of the symbiotic relationship between gut bacteria and the host, which promotes the development of metabolic diseases. In particular, the gut microbiota is believed to contribute to metabolic diseases via stimulation of low-grade inflammation.”  From a 2016 issue of Genome Medicine (Impact of the Gut Microbiota on Inflammation, Obesity, and Metabolic Disease)

There are two ways I typically date things; music and sporting events.  1976 was the year that the defending champion Big Red Machine (Cincinnati Reds) led by Joe Morgan, Pete Rose, Johnny Bench, and Ken Griffy, swept the hated Yankees (hey, I was a Royals fan). The Steelers squeaked by the Cowboys in the Super Bowl.  And set to the background of the imminent Bicentennial celebration, the pre-Larry Celtics won yet another NBA Championship.   Boston, Kansas, and the Eagles were on top of the music world, and Dr. KD Buchanan of Belfast Ireland’s Royal Victoria Hospital was publishing a study called The Gut as an Endocrine Organ. Huh? 

Not that I knew (or cared) one iota about this last fact in 1976 — for Pete’s sake I was only nine years old — but it shows you that despite not being “officially” considered one of the ENDOCRINE ORGANS, people have been talking about THE GUT as a hormone-producing gland for a very long time (actually Bayliss and Starling were making some of these discoveries in the late 1800’s). 

We know that the Gut itself produces a number of hormones, but what about the bugs that live there (Gut Flora / MICROBIOME)?  Considering what we already know (adipose tissue acts as an endocrine organ — HERE, Gut Health plays a critical role in almost all aspects of health — HERE, and fouled up flora can cause almost every health problem imaginable — HERE), it shouldn’t surprise us to see Gut Flora playing the role — quite probably a significant role —- as an endocrine organ.  Let’s just look at a few recent papers on this topic.  Oh, and just for fun, here are a few of the songs people were listening to in 1976.

(1976) E.L.O. 


(1976) QUEEN

  • BLAME IT ALL ON YOUR GUT / MICROBIOME CONNECTION:  Two years ago next month, FEMS Microbiology Reviews (Microbial Endocrinology: The Interplay Between the Microbiota and the Endocrine System) concluded that, “We now know that microbes influence metabolism, immunity and even behavior. One important but understudied mechanism appears to involve hormones. Although the precise pathways of microbiota-hormonal signaling have not yet been deciphered, specific changes in hormone levels correlate with the presence of the gut microbiota. The microbiota produces and secretes hormones, responds to host hormones and regulates expression levels of host hormones. We categorize these interactions by the different functions of the hormones, including those affecting behavior, sexual attraction, appetite and metabolism, gender, and immunity.”  This last sentence is interesting because I firmly believe that just like other neurological issues such as AUTISM, a significant part of our nation’s gender dysphoria can be tied to disturbances in the microbiome, right along with ENDOCRINE DISRUPTORS, MASS QUANTITIES OF SUGAR, and incessant CHEMICAL EXPOSURE.

  • IBS, SIBO, FODMAPS, AND THE LINK TO THE NEUROENDOCRINE FUNCTION OF GUT FLORA:  In 2012, the World Journal of Gastroenterology (Irritable Bowel Syndrome: Diagnosis and Pathogenesis) stated, “The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS: heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following: genetic factors, dietary intake, intestinal flora, or low-grade inflammation.  It is noteworthy that the role of FODMAPs and fibre on IBS symptoms is associated with intestinal flora.  Moreover, differences in the diet, intestinal flora and inflammation affect the NES of the gut. The release of different gut hormones depends on the composition and quantity of ingested food, as the food content of FODMAPs and fibre, intestinal flora and the subsequent fermentation can increase intestinal osmotic pressure. This change in intestinal pressure can stimulate hormonal release, such as the release of serotonin. Likewise, inflammation and the release of secretory products from immune cells effects hormonal release and the proliferation of gut endocrine cells.”  I have not yet mentioned it, but 90% of your body’s serotonin is manufactured in the Gut (HERE), which is why DEPRESSION is largely an inflammatory disease of the Gut.  And as far a herititilbity, remember that thanks to our knowledge of epigenetics this is not nearly as big a deal as many would have you believe (HERE). Not sure what SIBO and FODMAPS are?  That’s why I left you the links.

  • THE GUT MICROBIOME AFFECTS STEROID PRODUCTION I:  A 2015 issue of Acta Pharmica Sinica B said, “Bile acids are hormones that regulate their own synthesis, transport, in addition to glucose and lipid homeostasis, and energy balance. The gut microbial community through their capacity to produce bile acid metabolites distinct from the liver can be thought of as an “endocrine organ” with potential to alter host physiology, perhaps to their own favor.  We propose the term “sterolbiome” to describe the genetic potential of the gut microbiome to produce endocrine molecules form endogenous and exogenous steroids in the mammalian gut.”  Too many of these bile acids are associated with things like gallstones and even colon cancer, as well as having the potential to adversely affect FATTY ACID METABOLISM.  Follow along because in part II this process gets really crazy really fast.

  • THE GUT MICROBIOME AFFECTS STEROID PRODUCTION PART II.  A BOOST FOR BODYBUILDERS? / BANE FOR THOSE CONCERNED WITH PCOS:  What if there were a Gut bacteria that could turn the stress hormone CORTISOL — a hormone known for its ability to make you fat — into a precursor for testosterone?  If you are one of Dr. Eric Serrano’s merry band of hardcore strength athletes, this might (emphasis on might) be a good thing if you could somehow harness the process without creating a dysbiotic imbalance in the flora.  However, if you are a female who is already epigentically prone to PCOS, it could prove disastrous.  Four years ago this month, the Journal of Lipid Research discussed this potential in a study titled Clostridium Scindens: A Human Gut Microbe With a High Potential to Convert Glucocorticoids into Androgens (BTW, the term androgens refers to testosterone or its precursors).  The rub is that according to THIS STUDY from 1988, the very precursor being discussed here (11β-OHA) is used, “as an indicator… of excess androgen production in women with polycystic ovaries.

  • ENDOCRINE DYSFUNCTION (MICROBIOME INCLUDED) NOT ONLY MAKES YOU FAT BUT ADDICTS YOU TO UNHEALTHY FOODS:  Just last year, Dove Medical Press published Recent Findings Within the Microbiota–Gut–Brain–Endocrine Metabolic Interactome. These researchers concluded that, “There is no question that each species of gut bacteria engage in complex biochemistry with the host and host systems, which we refer to here as “co-metabolism”, namely, the metabolism that occurs between the microbiome and host metabolic systems, eg, metabolism derived from such organs as the liver, the kidney, and other human metabolic processes and enzymes,  In terms of one’s brain chemistry, leptin, ghrelin activity, and so forth are associated with the microbiota, and neurotransmitters involved in craving particular types of food, more than satiety factors, are the influence found with particular gut microbiota that can influence or help determine the types of foods you crave. Furthermore, the gut microbiota can reduce leptin sensitivity and the expression of obesity suppressing neuropeptides,”  An incredible study that’s free and online helps explain why ADDICTIVE FOODS grab hold of brain and hijack normal neuroendocrine pathways.

  • OBESITY, MICROBIOME, ENDOCRINE FUNCTION, AND FMT:  Last year, Frontiers in Cellular and Infection Microbiology (The New Era of Treatment for Obesity and Metabolic Disorders: Evidence and Expectations for Gut Microbiome Transplantation) concluded that yes, “microbes residing in the human gastrointestinal tract have been found to act as an endocrine organ.”  They went on to talk about the relationship between DYSBIOSIS and OBESITY by stating, “Despite the promotion of numerous strategies for the prevention and treatment of obesity, most patients are refractory to treatment. Thus, new approaches are currently being sought to reduce the financial, social, and health consequences of the obesity epidemic.  Recent research has implicated these microbes as having a significant role in the development of obesity, diabetes, and cardiovascular disease. Fecal microbiome transplantation has been suggested as a new method of altering the gut microbiota that may lead to beneficial metabolic changes.”  One more reason that FMT is the single most amazing therapy that no one you know has ever done — at least for anything other than C. DIFF.


  • GENETICS, EPIGENETICS, AND THE ENDOCRINE-LIKE GUT FLORA:  A likewise excellent overview of this whole process — this one from a 2013 issue of the Journal of Endocrinology (The Gut Microbiome: The Role of A Virtual Organ in the Endocrinology of the Host) — spells it out.  “In this review, we look at some of the best-characterized functions that only the gut microbiota plays and how it interacts with the host’s endocrine system and we try to make it clear that the 21st-century biology cannot afford to ignore this facet of biology, if it wants to fully understand what makes us human. In the last decade, the paradigm that the human genome is the predominant driver of host health has shifted towards a more superorganism-based viewpoint, with the microbiome playing a significant role in influencing host physiology and function.”  Once again we see epigenetics (factors you can control) trumping genetics (factors you cannot).  This is why it is critical to understand that your genetic makeup does not have as much power over your health as you have been led to believe (HERE).


  • GUT FLORA PRODUCES NUMEROUS SUBSTANCES THAT ACT AS HORMONES, INCLUDING VITAMINS:  In 2014, Oxford’s Molecular Endocrinology (Minireview: Gut Microbiota: The Neglected Endocrine Organ) concluded that, “The gut microbiota performs a number of essential protective, structural, and metabolic functions for host health, including food processing, digestion of complex host-indigestible polysaccharides, pathogen displacement, and synthesis of vitamins. As well as a direct action on the gut mucosa and the enteric nervous system (ENS), the metabolic output of the gut microbiota gives it a reach well beyond the local GI compartment. Thus, considering the ability to influence the function of distal organs and systems, in many respects, the gut microbiota resembles an endocrine organ. Through this lens, the microbiota produces numerous chemicals of a hormonal nature that are released into the bloodstream and act at distal sites.”  There were plenty of studies talking about the hormone we call Vitamin D as well as others.  My favorite expert on this topic of Gut-manufactured vitamins is Dr. Art Ayers (HERE). The other thing you need to be aware of is that despite what anyone tells you, there is a difference between natural vitamins (WHOLE FOOD VITAMINS) and synthetic chemical vitamins (HERE, HERE, and HERE). 


  • GUT FLORA PRODUCES HORMONES THAT AFFECT THE HEART VIA INFLAMMATORY PROCESSES:  Last Fall, the journal Molecular Metabolism (How Gut Microbes Talk to Organs: The Role of Endocrine and Nervous Routes) concluded that, “Changes in gut microbiota composition and activity have been associated with different metabolic disorders, including obesity, diabetes, and cardiometabolic disorders. Recent evidence suggests that different organs are directly under the influence of bacterial metabolites that may directly or indirectly regulate physiological and pathological processes.  We reviewed seminal as well as recent papers showing that gut microbes influence energy, glucose and lipid homeostasis by controlling different metabolic routes such as endocrine, enteric and central nervous system. These dialogues are discussed in the context of obesity and diabetes but also for brain pathologies and neurodegenerative disorders.  The recent advances in gut microbiota investigation as well as the discovery of specific metabolites interacting with host cells has led to the identification of novel inter-organ communication during metabolic disturbances.”  INFLAMMATION will destroy your life in 10,000 different ways if you let it (click the link for a short list)!  Tens of thousands of studies along these lines.  Stick around and I’ll show you how to help prevent / reverse the process.


  • CHEMICAL ENDOCRINE DISRUPTORS ADVERSELY AFFECT THE GUT FLORA:  An outrageously cool study from the March 2016 issue of Biofilms and Microbiomes (The Gut Microbiota: A Major Player in the Toxicity of Environmental Pollutants?) talked about the microbiome as an endocrine gland, and then discussed some of the ways that toxic chemicals (we frequently refer to these as “ENDOCRINE DISRUPTORS“) can foul the endocrine system up via fouling up the microbiome.  “Exposure to environmental chemicals has been linked to various health disorders, including obesity, type 2 diabetes, cancer and dysregulation of the immune and reproductive systems, whereas the gastrointestinal microbiota critically contributes to a variety of host metabolic and immune functions.  The literature indicates that gut microbes have an extensive capacity to metabolise environmental chemicals that can be classified in five core enzymatic families unequivocally involved in the metabolism of over 30 environmental contaminants. There is clear evidence that bacteria-dependent metabolism of pollutants modulates the toxicity for the host.  Conversely, environmental contaminants from various chemical families have been shown to alter the composition and/or the metabolic activity of the gastrointestinal bacteria, which may be an important factor contributing to shape an individual’s microbiotype.”  In other words, your microbiome plays a huge part in your DETOX AND BIOTRANSFORMATION pathways.  These chemicals have the ability to foul your microbiome to the point they can no longer clear said chemicals from their human environment, creating a vicious cycle.  HERE is another study that throws heavy metals (ALUMINUM and MERCURY), PESTICIDES, FOOD ADDITIVES, and ANTIBIOTICS into the microbiomal mix as well.  And if you are curious about BIOFILMS & HERXHEMER REACTIONS, just click the link.


  • THE BRAIN, MICROBIOTA, DEPRESSION, NEUROENDOCRINE, NEURO-DEGENERATION CONNECTION:  In 2013, the Polish journal Zurnal Mikrobiologii I Immunobiologii published a study called Intestinal-Brain Axis. Neuronal and Immune-Inflammatory Mechanisms of Brain and Intestine Pathology.  This study began by saying, “Mutually directed connections between intestine and brain are implemented by endocrine, neural and immune systems and nonspecific natural immunity. Intestine micro flora as an active participant of intestine-brain axis not only influences intestine functions but also stimulates the development of CNS in perinatal period and interacts with higher nervous centers causing depression and cognitive disorders in pathology.”  After discussing the critical role of the MICROGLIA / GLIAL CELLS, it’s final conclusions were that, “Glia implements neurotransmitter, immunologic, barrier and motoric functions in the intestine. An interconnection between intestine barrier function and hematoencephalic barrier regulation exists. Chronic endotoxinemia as a result of intestine barrier dysfunction forms sustained inflammation state of the brain with consequent destabilization of hematoencephalic barriers and spread of inflammation to other parts of the brain resulting in neurodegradation development.”  Catch this because it is important.  The Gut Barrier System (can anyone say “Leaky Gut?) is intimately related to the BBB (Blood Brain Barrier). When EITHER SYSTEM FAILS, the result is Leaky Gut Syndrome and Leaky Brain Syndrome, that allow inflammation to infiltrate the brain and CNS (which also causes “Leaky Cord / Nerve Syndrome”.  For the record, you can read about all of the various forms of “the leakies” simply by clicking the link.


  • THYROID PROBLEMS AND DYSBIOSIS:  The August 2015 issue of the journal Endocrine (Does Microbiota Composition Affect Thyroid Homeostasis?) “The role of the intestinal tract is crucial in the metabolism of nutrients, drugs, and hormones, including exogenous and endogenous iodothyronines as well as micronutrients involved in thyroid homeostasis. However, the link between thyroid homeostasis and microbiota composition is not yet completely ascertained. A pathogenetic link with dysbiosis has been described in different autoimmune disorders but not yet fully elucidated in autoimmune thyroid disease which represents the most frequent of them.”  Many experts have been talking about this link in detail for years (HERE).

Here’s the thing folks, not only could I have come up with way more bullets, I could have come up with numerous studies under each bullet.  If you have not yet figured out that GUT HEALTH is a critical aspect of your overall health — a veritable deal-breaker if it goes south — it may prove difficult to truly regain or maintain your health.  And this doesn’t even touch on the importance of FASCIA AS AN ENDOCRINE ORGAN.  To see what regaining your health and vitality (not to mention a normal weight) might look like, all you need to do is take a look at THIS SHORT POST.  Oh; and don’t forget to like, share, or follow on FACEBOOK as it’s the best way to reach those you care about most with high-impact health related information.

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