#RelevantResearch: 2017 Review-Estrogen-gut microbiome axis: Physiological and clinical implications.
As research continues to reveal more and more about the broad and intimate connections between gut health and other aspects of our health, such as the connections to the immune system, mood, and cognition, estrogen’s no exception! Estrogen has been shown to influence the gut microbiota (microbiome) and the reverse is also true, the gut microbiota can significantly impact estrogen levels! (1)
Microbiota: the microbe population living in your intestines (2)
How Does The Gut Impact Estrogen Levels?
The body can recycle estrogen, impacting circulating levels. This process takes place in the gut. The gut influences estrogen activity through what’s called beta-glucuronidase, which is an enzyme produced by certain strains of bacteria in your gut. Most inactive estrogen is bound to what’s called sex hormone binding globulin (SHBG), which the liver produces. (1) When estrogen is bound, it is inactive, and unable to initiate its “estrogenic” effect. However, beta-glucuronidase is able to free estrogen, to an unbound, biologically active state. When estrogen is unbound it is active and able to activate those estrogen receptors, to cause a downstream “estrogenic” effect.
It can be thought of as a big ol’ high-five, when estrogen activates estrogen receptors. When estrogen is bound, it’s like SHBG has wrapped up its arms and prevented estrogen from being able to raise a hand to pass on that high-five. However, when it’s free, it’s hands are free, and able to initiate that high-five (or activate that estrogen receptor😉).
Dysbiosis-What Is It, And What’s The Significance?
“An imbalance of the gut microbiota is referred to as dysbiosis and has pathophysiological consequences.” (1)
Dysbiosis is an imbalance in the microbes residing in your gut-too much of the bad, or ugly, and/or not enough of the good! This imbalance or skewed representation has been linked to health consequences which lead to disease and dysfunction. (1)
One of the potential consequences of dysbiosis is leaky gut.
“Gut epithelial barrier integrity has been shown to be influenced by dysbiosis through the reduction in cell–cell junctions leading to increased permeability and subsequently bacterial translocation . Bacterial translocation can lead to systemic inflammation leading to the exacerbation or induction of disease .” (1)
What this means is, an unhealthy gut microbiota has been shown to disrupt the cell-to-cell connections in the gut. You can think of it as a bunch of bridges connecting cells together in the single cell lining of the gut. Dysbiosis is capable of causing a loss of integrity to those bridges! This means that the cells are not held together as they should, allowing substances to gain entry into the body that normally would not be allowed in. Bacteria gaining access can lead to systemic inflammation sparking disease or making disease processes worse! (1)
The Vast Effects Of Estrogen Activity
We may think of estrogen as being only a female hormone having to do with the lady parts, puberty, and reproduction…However, this isn’t the full story. Men, you have estrogen too, just as ladies we have testosterone too. But getting back to estrogen, receptors are found in a variety of locations throughout the body. Where there’s a receptor, there’s the potential for estrogen’s effects to be triggered, through that downstream signalling! Estrogen receptors are found in the intestines, bone, brain, and (adipose) fat tissue, as a result estrogen has been shown to play a role in cardiovascular health, neural development, bone density and some cancers.(1)
Dysbiosis and Estrogen
Not all gut bacteria are able to produce beta-glucuronidase, and subsequently increase the level of circulating estrogens. Too many beta-glucuronidase producing bacteria, can propagate hyperestrogenic pathologies such as endometriosis and certain cancers.(1) That is, the gut microbiota of women with endometriosis may have a greater proportion of beta-glucuronidase producing bacteria, leading to more released circulating estrogens, driving endometriosis. (1) Whereas, too little beta-glucuronidase producing bacteria can contribute to hypoestrogenic pathologies such as metabolic syndrome, cardiovascular disease, and cognitive decline. (1) Diversity within your gut microbiome (or microbiota) is key, that is, there should be a diverse assortment of healthy microbes living in your gut!
Ways To Promote A Healthy Microbiota
Diet is crucial in establishing a healthy gut microbiota. Both sources of prebiotics and probiotics are applicable. Prebiotics are fermentable fibers that feed, nourish, and support the growth of beneficial microbes, whereas probiotics are those beneficial microbes themselves! These both can be consumed through the diet and through supplementation.
In general, healthy diets utilizing fiber, including plenty of vegetables, as well as fermented or cultured foods, will promote a hospitable environment to promote those good and varied strains of microbes. Whereas, antibiotic use negatively impacts your microbiota. Furthermore, lots of refined sugar, red meat, and processed foods, don’t set yourself up for success when it comes to the critters living in your gut. These factors not only deter the growth of beneficial bacteria; they can also feed those undesirable pathogens, fueling dysbiosis.
Diet is so important, and a pillar for health!