How Does Estrogen Impact The Gut? Introducing: The Estrobolome

ESTROGEN AND THE GUT WALL

Estrogen is commonly misconstrued as only having an important role in your reproductive system but estrogen receptors are located throughout your body, most notably in your gut and central nervous system (or your brain) [9]. Wherever estrogen receptors are present in the body means estrogen can bind to those cells and affect how that system functions. The Estrobolome is the name for a group of bacteria in the gut that processes and regulates estrogen levels thereby affecting estrogen concentrations in your bloodstream and organs [6,9,10]. In the gut, it also plays an important role in preventing permeability by acting as a physical barrier linking molecules together to make the walls stronger [6]. Dysbiosis of the gut bacteria can interfere with how estrogen is metabolized; either leading to a decrease or increase in circulating estrogen levels throughout the body as well as impacting the integrity of the gut wall mucosal barrier [6,10]. Increases in circulating estrogen levels in the body can lead to conditions such as metabolic syndrome, subfertility, PCOS and endometriosis [9]. Furthermore, as evidenced by women in their follicular phase when estrogen levels are high, increased circulating estrogen levels send a message to the gut to relax and decrease motility leading to further disruption in the absorption of nutrients and the excretion of waste products (a.k.a. slow motility)[9]. Conversely, decreased circulating levels of estrogen in the body can also cause metabolic syndromes but play a larger role in declining cognitive function, anxiety, depression and the stress response [9].

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