A Root Cause Medicine Approach
|
October 25, 2023

Interconnected Health: The Synergy of Hormones, Gut, and Immune Function

Medically Reviewed by
Updated On
September 17, 2024

The human body consists of multiple organ systems that work together to support vital bodily functions. Each of our body systems is interconnected and dependent on each other. For example, the heart (circulatory system) does not beat unless our brain (nervous system) sends signals telling it to. When one system is affected, it can have far-reaching consequences on the entire body. 

The gut, endocrine system, and immune system are in constant communication with each other through hormonal messengers, nerves, and microbial metabolites. Understanding and fostering the synergy between these systems is extremely important as chronic, inflammatory health conditions are on the rise, including autoimmune disease, metabolic syndrome, obesity, and cancer. Effective treatments of these conditions will investigate the relationship between these systems and involve interventions that don’t just target one affected system but also those connected to it.

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Overview of the Three Key Players

Before discussing how they are all connected, let's get started by reviewing the endocrine, gastrointestinal, and immune systems:

What is the Endocrine System?

The endocrine system, also known as our hormonal system, consists of several glands that produce and secrete hormones, which serve as the body’s messengers. They travel through the bloodstream, where they communicate with other tissues and organs to regulate biological functions such as metabolism, digestion, growth and development, mood, sexual function, sleep, and blood pressure.

What is the Gastrointestinal System & What is the Microbiome?

The gastrointestinal system consists of a series of organs connected to one another, from mouth to anus, responsible for the digestion of food and absorption of important nutrients. It is also home to trillions of microorganisms, known as the microbiome. These microorganisms have a variety of functions, including breaking down food compounds, synthesizing certain vitamins and amino acids, and interacting with our immune system.  Each person’s microbiome is unique and can change based on lifestyle factors, including diet, stress, and environmental exposures. Imbalances in the microbiome are associated with a variety of health issues, including gastrointestinal conditions like irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), metabolic syndrome, cardiovascular disease, depression, anxiety, skin conditions like psoriasis and eczema, and immune system dysregulation making individuals more susceptible to conditions like autoimmune diseases and allergies.

What is the Immune System?

The immune system is a network of organs and cells that recognizes and protects against foreign invaders to prevent infections and disease. The skin and mucous membranes serve as physical barriers and first-line defenders of the immune system. The bone marrow, thymus, and spleen are involved in white blood cell formation and storage. The white blood cells are responsible for searching for and destroying pathogens. The lymph nodes, tonsils, and adenoids help to trap foreign invaders. The gut secretes enzymes and contains the microbiome that prevents pathogen colonization. 

How Do Hormones Influence Gut Health and the Immune System?

Hormones influence gut health through a variety of mechanisms, including regulating motility, intestinal permeability, and the composition of the microbiome. Gastrointestinal motility refers to the movement of food through the gut to absorb nutrients and water while eliminating waste. This is accomplished by coordinated contractions and relaxations in the smooth muscles of the gastrointestinal tract, which are controlled by nerves, hormones, and immune system mediators. Ghrelin is a hormone secreted primarily by the stomach and small intestine that increases motility and gastric emptying.

Thyroid hormones also play a role in regulating motility, as demonstrated in the case of hypothyroid patients showing delayed transit times and reductions in motor activity in the stomach, small intestine, and colon. The gastrointestinal lining should be a semipermeable barrier, only allowing for the absorption of fully digested nutrients and water. Intestinal permeability, also known as leaky gut, occurs when this barrier gets disrupted, allowing larger molecules such as pathogens, toxins, and poorly digested food proteins to be absorbed. Certain hormones, like cortisol released during stress, can contribute to the breakdown of the gastrointestinal lining. In addition to inducing intestinal permeability, cortisol can disrupt the composition and overall diversity of the microbiome. Changes in sex hormones, like estrogen and progesterone, during pregnancy and menopause also influence the composition of the microbiome.

Hormones communicate with the immune system, helping to coordinate immune responses and maintain equilibrium within the immune system. When hormone levels become disrupted, several aspects of the immune system can be affected, increasing susceptibility to conditions such as autoimmune diseases and infections. Women are at a higher risk of developing autoimmune diseases than men. In part, this is likely due to sex hormones’ effects on immunity. Estrogen turns on genes for cytokines that coordinate immune responses against pathogens and can also exacerbate autoimmune responses. Furthermore, it activates B cells, a type of white blood cell that makes antibodies. Antibodies are proteins that mark and attack foreign substances and pathogens. In autoimmune diseases, B cells make autoantibodies against the body’s own tissues. Androgens, like testosterone, are largely immunosuppressive and can decrease the activity of immune cells involved in autoimmune reactions. Cortisol influences the activity of immune cells like B cells and T cells. Chronic, stress-induced elevations in cortisol suppress their activity and responsiveness, increasing susceptibility to infections.

How Does Gut Health Affect Hormonal and Immune Balance?

The gut influences both hormone production as well as metabolism. The lining of the gastrointestinal tract contains cells called enteroendocrine cells that release their own hormones. For example, when you eat, these cells release hormones like cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1) that regulate digestion and blood sugar. The gut also communicates with the brain to influence hormone production and regulation outside of the gastrointestinal tract. The gut microbiota produce neurotransmitters, like serotonin, that influence hormone production in the brain and short-chain fatty acids (SCFAs) that regulate hormone function, like improving insulin sensitivity.

Hormones are metabolized in the liver and then excreted into the bile for elimination through the stool. Certain strains of gut bacteria make an enzyme, beta-glucuronidase, that deconjugates these estrogen metabolites, allowing them to re-enter circulation and affect overall hormone balance. 

Between 70-80% of our immune cells are present in the gut, where they interact with the microbiome, influencing the development and activity of our immune system and protecting against infections. Commensal bacteria prevent pathogen colonization through nutrient and resource competition, maintaining proper pH levels in the GI tract, biofilm production, producing antimicrobial substances, stimulating secretory immunoglobulin A (IgA) production, and maintaining a healthy mucus layer.

Some microorganisms support the development of immune cells, known as regulatory T cells, that help to balance immune responses, while others can promote the activity of immune cells involved in inflammation. Alterations of the microbiome (dysbiosis) have been observed in autoimmune diseases. Under normal circumstances, the gastrointestinal lining would prevent pathogens and toxins from entering the bloodstream. When intestinal permeability is present, they are able to be absorbed and interact with the immune system, triggering inflammatory responses and increasing the risk of allergies and autoimmune diseases.

Factors contributing to the development of leaky gut and its relationship to autoimmune diseases. Adapted from: “Leaky Gut and Autoimmunity: An Intricate Balance in Individuals Health and the Diseased State” by B.A. Paray, 2020, International Journal of Molecular Science, 21(24). https://www.mdpi.com/1422-0067/21/24/9770

How Does the Immune System Affect Hormones and Gut Health?

As previously discussed, chronic stress and its associated hormonal responses have a profound impact on immune function. It's important to note that this connection operates as a bidirectional relationship. Immune cells release signaling molecules called cytokines in response to infection or inflammation. These cytokines affect the function of the hypothalamus-pituitary-adrenal (HPA) axis and stimulate the release of stress hormones like cortisol. These inflammatory cytokines can also affect the hypothalamus-pituitary-gonadal (HPG) axis and the production of hormones like gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) involved in fertility and reproduction.  Inflammation can directly impact ovarian function and hormone production, as seen in the case of polycystic ovarian syndrome (PCOS), where chronic inflammation is linked to excess androgen production.

The immune system in the gut, called the gut-associated lymphoid tissue (GALT), is responsible for identifying and removing pathogens. The GALT is in constant contact with the commensal microorganisms in the gut and must maintain immune tolerance toward them, requiring properly functioning regulatory T cells. Dysregulated GALT function is associated with gastrointestinal conditions like inflammatory bowel disease. Increased immune system activity and inflammation, such as during active infections, impact gastrointestinal motility, most likely through smooth muscle contractility. Systemic autoimmune diseases can also cause gastrointestinal issues through mechanisms like immune complex deposition and chronic exposure to inflammatory cytokines.

How Can Lab Testing Be Used to Evaluate Hormones, Gut Health, and The Immune System?

Functional medicine labs provide an opportunity to explore the complex interactions between the gut, hormones, and immune system that might otherwise be missed. By ordering these labs in tandem, rather than analyzing these systems in isolation, practitioners can identify the root causes of patients’ dysfunction and personalize holistic treatment plans accordingly.

Gut Health Tests

The GI Effects test by Genova Diagnostics provides insight into microbiome composition, gastrointestinal inflammation, and digestive capacity. Using both culture and polymerase chain reaction (PCR) analysis, the test can reveal the relative amounts of important commensal bacteria as well as identify any potential pathogens like bacteria, fungi, and parasites. Elevations in markers like calprotectin, a protein produced by neutrophils, and eosinophil protein X (EPX) can indicate increased immune system activity in the gut. 

Cyrex’s Array 2, also known as the Intestinal Antigenic Permeability Screen, measures antibodies against specific proteins associated with the gut lining to assess intestinal permeability.

Hormone Panels

There are various testing methods available to measure hormones, including blood, saliva, and urine. Although blood tests are the traditional choice for identifying endocrine conditions, there are also advantages to saliva and urine tests. They provide non-invasive alternatives for patients desiring a more comfortable collection experience and can also reveal additional information about free or bioavailable hormone levels and hormone metabolism.

The DUTCH Complete is a dried urine test that not only measures cortisol, DHEA, estrogen, progesterone, and testosterone but also their metabolites. Like the salivary hormone profile, it measures cortisol levels at multiple points throughout the day to uncover any deviations from the normal circadian rhythm. It also includes melatonin, a hormone involved in regulating our sleep-wake cycle, that is not included in the other testing options mentioned.

Immune System Function Tests

The assessment of immune markers in lab testing can identify immune system dysfunction like a weakened immune system, inflammation, and autoimmunity. 

A complete blood count with differential (CBC w/ diff) measures the total amount of white blood cells as well as the breakdown of the various types of white blood cells including neutrophils, lymphocytes, eosinophils, monocytes, and basophils. Changes in these markers provide information about what type of immune responses might be occurring. For example, low white blood cells can indicate a weakened immune system or immune system suppression, elevated eosinophils can occur in allergies or parasitic infections, and elevated neutrophils are often seen in bacterial infections. 

Immunoglobulins are proteins secreted by immune cells to identify and neutralize foreign substances and pathogens. The Immunoglobulins Panel by Access Medical Laboratories measures the total amount of various immunoglobulins (IgA, IgG, and IgM), reporting whether the immune system is struggling to produce enough immunoglobulins, as seen in immune deficiency states, or producing too many, as seen in chronic inflammatory conditions.

Exposure to chronic infections can impact the body’s immune responses, potentially depleting the immune system, promoting inflammation, and/or triggering autoimmunity. (6, 7, 65).

Antinuclear antibodies (ANA) are a type of autoantibody commonly seen in autoimmune disease. If ANA is positive, an extractable nuclear antigen (ENA) test can be ordered to help identify more specifically which autoimmune disease is present.

C-reactive protein (CRP) is a protein released from the liver in the presence of inflammation. Sedimentation rate (ESR) measures the rate at which red blood cells settle at the bottom of the collection test tube. If inflammation is present, the red blood cells tend to clump together and settle more quickly, causing a higher ESR. Both of these markers tend to be elevated in autoimmune diseases.

Holistic Interventions for Balanced Interconnectivity

Holistic treatment plans for the gut-hormone-immune axis include multi-faceted and personalized interventions designed with the relationship of these essential body systems in mind to optimize interconnected health. 

Nutrition for Balanced Gut Health, Hormones, and Immune Systems

A whole-foods, nutrient-dense, and high-fiber diet can support optimal hormone balance, gastrointestinal function, and immunity. (19, 47, 66)

An example of such a diet would be the Mediterranean diet, which emphasizes fruits, vegetables, legumes, whole grains, and healthy fats and restricts processed meats, foods, sugars, and oils. High-fiber plant foods help to support beneficial microbiome diversity in the gastrointestinal tract. Vitamins, minerals, and phytonutrients found in fruits and vegetables help support hormone production and metabolism as well as immune system function (8, 54). Removing inflammatory foods like processed sugars and trans fats helps to prevent both gastrointestinal and systemic inflammation that can disrupt the gut-hormone-immune axis. (11)

Lifestyle Adjustments for a Healthy Gut, Hormones, and Immune System

Sleep deprivation is associated with changes to immune system function, changes to microbiome composition, and hormone imbalances.  The National Sleep Foundation recommends 7-9 hours of sleep for adults. Some good sleep hygiene practices to implement to improve sleep quality include: stick to a consistent sleep schedule, get daytime natural light exposure, make sure the bedroom is cool, dark and quiet, limit screen exposure in the evenings, and avoid heavy meals and caffeine too close to bedtime.

Stress management techniques, like meditation and breathing exercises, help to regulate the HPA axis and cortisol levels. Stress management techniques have been used to improve symptoms in gastrointestinal conditions, reduce inflammatory cytokines, and balance hormones besides just cortisol, including DHEA, melatonin, and testosterone. 

Adding an exercise routine into your weekly schedule can help to balance the gut-hormone-immune axis. Regular physical activity enhances the amounts of beneficial microorganisms in the microbiome, improves sleep quality, reduces inflammation, strengthens the immune system, and regulates hormone production and function. (23, 50)

Herbs & Supplements for a Healthy Gut, Hormones, and Immune System

Probiotics and Ashwagandha are incredibly helpful for supporting a healthy gut, keeping hormones balanced, and supporting a healthy immune system.

Probiotics

Probiotics are supplements that contain live microorganisms like healthy bacteria and yeast. Probiotics improve gut and immune function by improving microbiome diversity, enhancing intestinal barrier function, and preventing pathogens from colonizing in the GI tract. They also interact with immune cells in the gastrointestinal tract to modulate immune cell activity.  Probiotics are also useful in treating hormonal disturbances, like PCOS, insulin resistance, and stress-induced cortisol imbalances.

Ashwagandha

Ashwagandha, or Withania Somnifera, is an herbal adaptogen. Adaptogens help the body to adapt stress and maintain homeostasis. Ashwagandha has been used to calm stress, reduce cortisol, balance the immune system, and inhibit the growth of pathogens. These mechanisms of action can help to strengthen the gut-hormone-immune axis.

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Summary

The interdependence between the body’s systems is particularly evident in the complex relationship between the gastrointestinal, endocrine, and immune systems. Dysregulation in gut health, hormones, or immunity (or all three) can increase the susceptibility to various disease states. As we continue to deal with increasing prevalence of chronic health conditions, it becomes increasingly evident that the key to successful management lies in considering and investigating the interconnectedness of these body systems to create personalized and holistic treatment plans.

The human body consists of multiple organ systems that work together to support vital bodily functions. Each of our body systems is interconnected and dependent on each other. For example, the heart (circulatory system) does not beat unless our brain (nervous system) sends signals telling it to. When one system is affected, it can have far-reaching consequences on the entire body. 

The gut, endocrine system, and immune system are in constant communication with each other through hormonal messengers, nerves, and microbial metabolites. Understanding and fostering the synergy between these systems is extremely important as chronic, inflammatory health conditions are on the rise, including autoimmune disease, metabolic syndrome, obesity, and cancer. Effective management of these conditions may involve exploring the relationship between these systems and considering interventions that support overall health and well-being.

[signup]

Overview of the Three Key Players

Before discussing how they are all connected, let's get started by reviewing the endocrine, gastrointestinal, and immune systems:

What is the Endocrine System?

The endocrine system, also known as our hormonal system, consists of several glands that produce and secrete hormones, which serve as the body’s messengers. They travel through the bloodstream, where they communicate with other tissues and organs to regulate biological functions such as metabolism, digestion, growth and development, mood, sexual function, sleep, and blood pressure.

What is the Gastrointestinal System & What is the Microbiome?

The gastrointestinal system consists of a series of organs connected to one another, from mouth to anus, responsible for the digestion of food and absorption of important nutrients. It is also home to trillions of microorganisms, known as the microbiome. These microorganisms have a variety of functions, including breaking down food compounds, synthesizing certain vitamins and amino acids, and interacting with our immune system.  Each person’s microbiome is unique and can change based on lifestyle factors, including diet, stress, and environmental exposures. Imbalances in the microbiome are associated with a variety of health issues, including gastrointestinal conditions like irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), metabolic syndrome, cardiovascular disease, depression, anxiety, skin conditions like psoriasis and eczema, and immune system dysregulation making individuals more susceptible to conditions like autoimmune diseases and allergies.

What is the Immune System?

The immune system is a network of organs and cells that recognizes and protects against foreign invaders to help maintain health. The skin and mucous membranes serve as physical barriers and first-line defenders of the immune system. The bone marrow, thymus, and spleen are involved in white blood cell formation and storage. The white blood cells are responsible for searching for and responding to pathogens. The lymph nodes, tonsils, and adenoids help to trap foreign invaders. The gut secretes enzymes and contains the microbiome that supports a healthy balance of microorganisms. 

How Do Hormones Influence Gut Health and the Immune System?

Hormones influence gut health through a variety of mechanisms, including regulating motility, intestinal permeability, and the composition of the microbiome. Gastrointestinal motility refers to the movement of food through the gut to absorb nutrients and water while eliminating waste. This is accomplished by coordinated contractions and relaxations in the smooth muscles of the gastrointestinal tract, which are controlled by nerves, hormones, and immune system mediators. Ghrelin is a hormone secreted primarily by the stomach and small intestine that increases motility and gastric emptying.

Thyroid hormones also play a role in regulating motility, as demonstrated in the case of hypothyroid patients showing delayed transit times and reductions in motor activity in the stomach, small intestine, and colon. The gastrointestinal lining should be a semipermeable barrier, only allowing for the absorption of fully digested nutrients and water. Intestinal permeability, also known as leaky gut, occurs when this barrier gets disrupted, allowing larger molecules such as pathogens, toxins, and poorly digested food proteins to be absorbed. Certain hormones, like cortisol released during stress, can contribute to the breakdown of the gastrointestinal lining. In addition to inducing intestinal permeability, cortisol can disrupt the composition and overall diversity of the microbiome. Changes in sex hormones, like estrogen and progesterone, during pregnancy and menopause also influence the composition of the microbiome.

Hormones communicate with the immune system, helping to coordinate immune responses and maintain equilibrium within the immune system. When hormone levels become disrupted, several aspects of the immune system can be affected, increasing susceptibility to conditions such as autoimmune diseases and infections. Women are at a higher risk of developing autoimmune diseases than men. In part, this is likely due to sex hormones’ effects on immunity. Estrogen turns on genes for cytokines that coordinate immune responses against pathogens and can also exacerbate autoimmune responses. Furthermore, it activates B cells, a type of white blood cell that makes antibodies. Antibodies are proteins that mark and attack foreign substances and pathogens. In autoimmune diseases, B cells make autoantibodies against the body’s own tissues. Androgens, like testosterone, are largely immunosuppressive and can decrease the activity of immune cells involved in autoimmune reactions. Cortisol influences the activity of immune cells like B cells and T cells. Chronic, stress-induced elevations in cortisol suppress their activity and responsiveness, increasing susceptibility to infections.

How Does Gut Health Affect Hormonal and Immune Balance?

The gut influences both hormone production as well as metabolism. The lining of the gastrointestinal tract contains cells called enteroendocrine cells that release their own hormones. For example, when you eat, these cells release hormones like cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1) that regulate digestion and blood sugar. The gut also communicates with the brain to influence hormone production and regulation outside of the gastrointestinal tract. The gut microbiota produce neurotransmitters, like serotonin, that influence hormone production in the brain and short-chain fatty acids (SCFAs) that regulate hormone function, like improving insulin sensitivity.

Hormones are metabolized in the liver and then excreted into the bile for elimination through the stool. Certain strains of gut bacteria make an enzyme, beta-glucuronidase, that deconjugates these estrogen metabolites, allowing them to re-enter circulation and affect overall hormone balance. 

Between 70-80% of our immune cells are present in the gut, where they interact with the microbiome, influencing the development and activity of our immune system and protecting against infections. Commensal bacteria prevent pathogen colonization through nutrient and resource competition, maintaining proper pH levels in the GI tract, biofilm production, producing antimicrobial substances, stimulating secretory immunoglobulin A (IgA) production, and maintaining a healthy mucus layer.

Some microorganisms support the development of immune cells, known as regulatory T cells, that help to balance immune responses, while others can promote the activity of immune cells involved in inflammation. Alterations of the microbiome (dysbiosis) have been observed in autoimmune diseases. Under normal circumstances, the gastrointestinal lining would prevent pathogens and toxins from entering the bloodstream. When intestinal permeability is present, they are able to be absorbed and interact with the immune system, triggering inflammatory responses and increasing the risk of allergies and autoimmune diseases.

Factors contributing to the development of leaky gut and its relationship to autoimmune diseases. Adapted from: “Leaky Gut and Autoimmunity: An Intricate Balance in Individuals Health and the Diseased State” by B.A. Paray, 2020, International Journal of Molecular Science, 21(24). https://www.mdpi.com/1422-0067/21/24/9770

How Does the Immune System Affect Hormones and Gut Health?

As previously discussed, chronic stress and its associated hormonal responses have a profound impact on immune function. It's important to note that this connection operates as a bidirectional relationship. Immune cells release signaling molecules called cytokines in response to infection or inflammation. These cytokines affect the function of the hypothalamus-pituitary-adrenal (HPA) axis and stimulate the release of stress hormones like cortisol. These inflammatory cytokines can also affect the hypothalamus-pituitary-gonadal (HPG) axis and the production of hormones like gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) involved in fertility and reproduction.  Inflammation can directly impact ovarian function and hormone production, as seen in the case of polycystic ovarian syndrome (PCOS), where chronic inflammation is linked to excess androgen production.

The immune system in the gut, called the gut-associated lymphoid tissue (GALT), is responsible for identifying and removing pathogens. The GALT is in constant contact with the commensal microorganisms in the gut and must maintain immune tolerance toward them, requiring properly functioning regulatory T cells. Dysregulated GALT function is associated with gastrointestinal conditions like inflammatory bowel disease. Increased immune system activity and inflammation, such as during active infections, impact gastrointestinal motility, most likely through smooth muscle contractility. Systemic autoimmune diseases can also cause gastrointestinal issues through mechanisms like immune complex deposition and chronic exposure to inflammatory cytokines.

How Can Lab Testing Be Used to Evaluate Hormones, Gut Health, and The Immune System?

Functional medicine labs provide an opportunity to explore the complex interactions between the gut, hormones, and immune system that might otherwise be missed. By ordering these labs in tandem, rather than analyzing these systems in isolation, practitioners can identify the root causes of patients’ dysfunction and personalize holistic treatment plans accordingly.

Gut Health Tests

The GI Effects test by Genova Diagnostics provides insight into microbiome composition, gastrointestinal inflammation, and digestive capacity. Using both culture and polymerase chain reaction (PCR) analysis, the test can reveal the relative amounts of important commensal bacteria as well as identify any potential pathogens like bacteria, fungi, and parasites. Elevations in markers like calprotectin, a protein produced by neutrophils, and eosinophil protein X (EPX) can indicate increased immune system activity in the gut. 

Cyrex’s Array 2, also known as the Intestinal Antigenic Permeability Screen, measures antibodies against specific proteins associated with the gut lining to assess intestinal permeability.

Hormone Panels

There are various testing methods available to measure hormones, including blood, saliva, and urine. Although blood tests are the traditional choice for identifying endocrine conditions, there are also advantages to saliva and urine tests. They provide non-invasive alternatives for patients desiring a more comfortable collection experience and can also reveal additional information about free or bioavailable hormone levels and hormone metabolism.

The DUTCH Complete is a dried urine test that not only measures cortisol, DHEA, estrogen, progesterone, and testosterone but also their metabolites. Like the salivary hormone profile, it measures cortisol levels at multiple points throughout the day to uncover any deviations from the normal circadian rhythm. It also includes melatonin, a hormone involved in regulating our sleep-wake cycle, that is not included in the other testing options mentioned.

Immune System Function Tests

The assessment of immune markers in lab testing can identify immune system dysfunction like a weakened immune system, inflammation, and autoimmunity. 

A complete blood count with differential (CBC w/ diff) measures the total amount of white blood cells as well as the breakdown of the various types of white blood cells including neutrophils, lymphocytes, eosinophils, monocytes, and basophils. Changes in these markers provide information about what type of immune responses might be occurring. For example, low white blood cells can indicate a weakened immune system or immune system suppression, elevated eosinophils can occur in allergies or parasitic infections, and elevated neutrophils are often seen in bacterial infections. 

Immunoglobulins are proteins secreted by immune cells to identify and neutralize foreign substances and pathogens. The Immunoglobulins Panel by Access Medical Laboratories measures the total amount of various immunoglobulins (IgA, IgG, and IgM), reporting whether the immune system is struggling to produce enough immunoglobulins, as seen in immune deficiency states, or producing too many, as seen in chronic inflammatory conditions.

Exposure to chronic infections can impact the body’s immune responses, potentially depleting the immune system, promoting inflammation, and/or triggering autoimmunity. (6, 7, 65).

Antinuclear antibodies (ANA) are a type of autoantibody commonly seen in autoimmune disease. If ANA is positive, an extractable nuclear antigen (ENA) test can be ordered to help identify more specifically which autoimmune disease is present.

C-reactive protein (CRP) is a protein released from the liver in the presence of inflammation. Sedimentation rate (ESR) measures the rate at which red blood cells settle at the bottom of the collection test tube. If inflammation is present, the red blood cells tend to clump together and settle more quickly, causing a higher ESR. Both of these markers tend to be elevated in autoimmune diseases.

Holistic Interventions for Balanced Interconnectivity

Holistic treatment plans for the gut-hormone-immune axis include multi-faceted and personalized interventions designed with the relationship of these essential body systems in mind to optimize interconnected health. 

Nutrition for Balanced Gut Health, Hormones, and Immune Systems

A whole-foods, nutrient-dense, and high-fiber diet can support optimal hormone balance, gastrointestinal function, and immunity. (19, 47, 66)

An example of such a diet would be the Mediterranean diet, which emphasizes fruits, vegetables, legumes, whole grains, and healthy fats and restricts processed meats, foods, sugars, and oils. High-fiber plant foods help to support beneficial microbiome diversity in the gastrointestinal tract. Vitamins, minerals, and phytonutrients found in fruits and vegetables help support hormone production and metabolism as well as immune system function (8, 54). Removing inflammatory foods like processed sugars and trans fats helps to prevent both gastrointestinal and systemic inflammation that can disrupt the gut-hormone-immune axis. (11)

Lifestyle Adjustments for a Healthy Gut, Hormones, and Immune System

Sleep deprivation is associated with changes to immune system function, changes to microbiome composition, and hormone imbalances.  The National Sleep Foundation recommends 7-9 hours of sleep for adults. Some good sleep hygiene practices to implement to improve sleep quality include: stick to a consistent sleep schedule, get daytime natural light exposure, make sure the bedroom is cool, dark and quiet, limit screen exposure in the evenings, and avoid heavy meals and caffeine too close to bedtime.

Stress management techniques, like meditation and breathing exercises, help to regulate the HPA axis and cortisol levels. Stress management techniques have been used to improve symptoms in gastrointestinal conditions, reduce inflammatory cytokines, and balance hormones besides just cortisol, including DHEA, melatonin, and testosterone. 

Adding an exercise routine into your weekly schedule can help to balance the gut-hormone-immune axis. Regular physical activity enhances the amounts of beneficial microorganisms in the microbiome, improves sleep quality, reduces inflammation, strengthens the immune system, and regulates hormone production and function. (23, 50)

Herbs & Supplements for a Healthy Gut, Hormones, and Immune System

Probiotics and Ashwagandha are options that may support a healthy gut, help maintain balanced hormones, and support a healthy immune system.

Probiotics

Probiotics are supplements that contain live microorganisms like healthy bacteria and yeast. Probiotics may support gut and immune function by promoting microbiome diversity, enhancing intestinal barrier function, and helping to maintain a healthy balance of microorganisms in the GI tract. They also interact with immune cells in the gastrointestinal tract to modulate immune cell activity.  Probiotics are also being explored for their potential in supporting hormonal balance, such as in PCOS, insulin resistance, and stress-related cortisol imbalances.

Ashwagandha

Ashwagandha, or Withania Somnifera, is an herbal adaptogen. Adaptogens may help the body adapt to stress and maintain homeostasis. Ashwagandha has been used to help manage stress, support balanced cortisol levels, and promote a healthy immune system. These mechanisms of action can help to support the gut-hormone-immune axis.

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Summary

The interdependence between the body’s systems is particularly evident in the complex relationship between the gastrointestinal, endocrine, and immune systems. Dysregulation in gut health, hormones, or immunity (or all three) can increase the susceptibility to various health challenges. As we continue to deal with increasing prevalence of chronic health conditions, it becomes increasingly evident that the key to successful management lies in considering and investigating the interconnectedness of these body systems to create personalized and holistic approaches.

The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.

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Lab Tests in This Article

  1. Akiho, H. (2011). Cytokine-induced alterations of gastrointestinal motility in gastrointestinal disorders. World Journal of Gastrointestinal Pathophysiology, 2(5), 72. https://doi.org/10.4291/wjgp.v2.i5.72
  2. Andersson, H., Tullberg, C., Ahrné, S., Hamberg, K., Lazou Ahrén, I., Molin, G., Sonesson, M., & Håkansson, Å. (2016). Oral Administration of lactobacillus plantarum 299v reduces cortisol levels in human saliva during examination induced stress: A randomized, double-blind controlled trial. International Journal of Microbiology, 2016, 1–7. https://doi.org/10.1155/2016/8469018
  3. Angoorani, P., Ejtahed, H.-S., Ettehad Marvasti, F., Taghavi, M., Mohammadpour Ahranjani, B., Hasani-Ranjbar, S., & Larijani, B. (2023). The effects of probiotics, prebiotics, and synbiotics on polycystic ovarian syndrome: An overview of systematic reviews. Frontiers in Medicine, 10. https://doi.org/10.3389/fmed.2023.1141355
  4. Beavers, K. M., Brinkley, T. E., & Nicklas, B. J. (2010). Effect of exercise training on chronic inflammation. Clinica Chimica Acta, 411(11–12), 785–793. https://doi.org/10.1016/j.cca.2010.02.069
  5. Belkaid, Y., & Hand, T. W. (2014). Role of the microbiota in immunity and inflammation. Cell, 157(1), 121–141. https://doi.org/10.1016/j.cell.2014.03.011
  6. Brooks, D. G., Tishon, A., Oldstone, M. B., & McGavern, D. B. (2021). Prevention of CD8 T cell deletion during chronic viral infection. Viruses, 13(7), 1189. https://doi.org/10.3390/v13071189
  7. Casanova, J.-L., & Abel, L. (2021). Mechanisms of viral inflammation and disease in humans. Science, 374(6571), 1080–1086. https://doi.org/10.1126/science.abj7965
  8. Casas, R., Sacanella, E., & Estruch, R. (2014). The immune protective effect of the Mediterranean diet against chronic low-grade inflammatory diseases. Endocrine, Metabolic & Immune Disorders-Drug Targets, 14(4), 245–254. https://doi.org/10.2174/1871530314666140922153350
  9. Chandran, P., Satthaporn, S., Robins, A., & Eremin, O. (2003). Inflammatory bowel disease: Dysfunction of GALT and gut bacterial flora (I). The Surgeon, 1(2), 63–75. https://doi.org/10.1016/s1479-666x(03)80118-x
  10. Choukèr, A., Fagundes, C. P., & Christian, L. M. (2019). The Impact of Everyday Stressors on the Immune System and Health. In Stress challenges and immunity in space: From mechanisms to monitoring and preventive strategies (pp. 71–92). essay, Springer Nature.
  11. Clemente-Suárez, V. J., Beltrán-Velasco, A. I., Redondo-Flórez, L., Martín-Rodríguez, A., & Tornero-Aguilera, J. F. (2023, June 14). Global impacts of western diet and its effects on metabolism and Health: A Narrative Review. Nutrients. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10302286/
  12. Cloyd, J. (2022, December 8). Inflammatory Bowel Disease: Treatments for IBD Flares and Remission. Rupa Health. https://www.rupahealth.com/post/inflammatory-bowel-disease-ibd-treatments-for-flares-and-remission
  13. Cloyd, J. (2023, February 28). A functional medicine protocol for Leaky Gut Syndrome. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-protocol-for-leaky-gut-syndrome
  14. Cloyd, J. (2023, May 17). The role of nutrition and dietary supplements in preventing and managing cardiovascular disease. Rupa Health. https://www.rupahealth.com/post/the-role-of-nutrition-and-dietary-supplements-in-preventing-and-managing-cardiovascular-disease
  15. Cloyd, J. (2023, July 7). A functional medicine eczema protocol: Testing, nutrition, and supplements. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-eczema-protocol-testing-nutrition-and-supplements
  16. Cloyd, J. (2023, July 20). A functional medicine PCOS protocol: Comprehensive Testing, Therapeutic Diet, and supplements. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-pcos-protocol-comprehensive-testing-therapeutic-diet-and-supplements
  17. Cloyd, J. (2023, August 21). A root cause medicine protocol for patients with psoriasis: Comprehensive lab testing, therapeutic diet, and supplements. Rupa Health. https://www.rupahealth.com/post/a-root-cause-medicine-protocol-for-patients-with-psoriasis-comprehensive-lab-testing-therapeutic-diet-and-supplements
  18. Cloyd, J. (2023, September 25). An integrative medicine approach to understanding sleep’s role in a healthy immune system. Rupa Health. https://www.rupahealth.com/post/an-integrative-medicine-approach-to-understanding-sleeps-role-in-a-healthy-immune-system
  19. Cloyd, K. (2023, October 3). Functional medicine protocol for autoimmune diseases: Balancing the immune system. Rupa Health. https://www.rupahealth.com/post/functional-medicine-protocol-for-autoimmune-diseases-balancing-the-immune-system
  20. Cojocaru, M., Cojocaru, I. M., Silosi, I., & Vrabie, C. D. (2011). Gastrointestinal Manifestations in Systemic Autoimmune Diseases. Maedica Journal of Clinical Medicine, 6(1), 45–51.
  21. Conner, V. (2022, July 13). This virus has infected over 90% of the adult population. yet many never experience any symptoms. Rupa Health. https://www.rupahealth.com/post/epstein-barr-virus-ebv
  22. Creswell, J. D., Taren, A. A., Lindsay, E. K., Greco, C. M., Gianaros, P. J., Fairgrieve, A., Marsland, A. L., Brown, K. W., Way, B. M., Rosen, R. K., & Ferris, J. L. (2016). Alterations in resting-state functional connectivity link mindfulness meditation with reduced interleukin-6: A randomized controlled trial. Biological Psychiatry, 80(1), 53–61. https://doi.org/10.1016/j.biopsych.2016.01.008
  23. Cumming, D. C., Brunsting, L. A., Strich, G., Ries, A. L., & Rebar, R. W. (1986). Reproductive hormone increases in response to acute exercise in men. Medicine & Science in Sports & Exercise, 18(4). https://doi.org/10.1249/00005768-198608000-00001
  24. da Silveira, M. P., da Silva Fagundes, K. K., Bizuti, M. R., Starck, É., Rossi, R. C., & de Resende e Silva, D. T. (2020). Physical exercise as a tool to help the immune system against COVID-19: An integrative review of the current literature. Clinical and Experimental Medicine, 21(1), 15–28. https://doi.org/10.1007/s10238-020-00650-3
  25. Dicks, L. M. (2022). Gut bacteria and neurotransmitters. Microorganisms, 10(9), 1838. https://doi.org/10.3390/microorganisms10091838
  26. Digestive system: Function, Organs & Anatomy. Cleveland Clinic. (n.d.-a). https://my.clevelandclinic.org/health/body/7041-digestive-system
  27. Endocrine system: What is it, functions & organs. Cleveland Clinic. (n.d.-b). https://my.clevelandclinic.org/health/body/21201-endocrine-system
  28. English, J., Connolly, L., & Stewart, L. D. (2023). Increased intestinal permeability: An avenue for the development of autoimmune disease? Exposure and Health. https://doi.org/10.1007/s12403-023-00578-5
  29. Greenan, S. (2021, November 5). A functional medicine approach to IBS. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-approach-to-ibs
  30. Gribble, F. M., & Reimann, F. (2019). Function and mechanisms of enteroendocrine cells and gut hormones in metabolism. Nature Reviews Endocrinology, 15(4), 226–237. https://doi.org/10.1038/s41574-019-0168-8
  31. Gubbels Bupp, M. R., & Jorgensen, T. N. (2018). Androgen-induced immunosuppression. Frontiers in Immunology, 9. https://doi.org/10.3389/fimmu.2018.00794 
  32. Harvard T.H. Chan School of Public Health. (2022, July 25). The microbiome. The Nutrition Source. https://www.hsph.harvard.edu/nutritionsource/microbiome/
  33. Henry, K. (2023, February 21). An integrative medicine approach to Depression. Rupa Health. https://www.rupahealth.com/post/an-integrative-medicine-approach-to-depression
  34. Henry, K. (2023, March 21). An integrative medicine team approach to treating anxiety. Rupa Health. https://www.rupahealth.com/post/an-integrative-medicine-team-approach-to-treating-anxiety
  35. Hoge, E. A., Bui, E., Palitz, S. A., Schwarz, N. R., Owens, M. E., Johnston, J. M., Pollack, M. H., & Simon, N. M. (2018). The effect of mindfulness meditation training on biological acute stress responses in generalized anxiety disorder. Psychiatry Research, 262, 328–332. https://doi.org/10.1016/j.psychres.2017.01.006
  36. Hopper, S. I., Murray, S. L., Ferrara, L. R., & Singleton, J. K. (2019). Effectiveness of diaphragmatic breathing for reducing physiological and psychological stress in adults: A quantitative systematic review. JBI Database of Systematic Reviews and Implementation Reports, 17(9), 1855–1876. https://doi.org/10.11124/jbisrir-2017-003848
  37. Hu, S., Ding, Q., Zhang, W., Kang, M., Ma, J., & Zhao, L. (2023). Gut microbial beta-glucuronidase: A vital regulator in female estrogen metabolism. Gut Microbes, 15(1). https://doi.org/10.1080/19490976.2023.2236749
  38. Ibrahim Abdalla, M. M. (2015). Ghrelin – physiological functions and regulation. European Endocrinology, 11(2), 90. https://doi.org/10.17925/ee.2015.11.02.90
  39. Immune system: Parts & common problems. Cleveland Clinic. (n.d.-c). https://my.clevelandclinic.org/health/body/21196-immune-system
  40. Kanchibhotla, D., Sharma, P., & Subramanian, S. (2021). Improvement in gastrointestinal quality of life index (GIQLI) following meditation: An open-trial pilot study in India. Journal of Ayurveda and Integrative Medicine, 12(1), 107–111. https://doi.org/10.1016/j.jaim.2021.01.006
  41. Khakham, C. K. (2023, June 8). Exploring the complexities of autoimmune diseases: Unraveling mechanisms, risk factors, and integrative approaches to testing, diagnosis, and treatment. Rupa Health. https://www.rupahealth.com/post/understanding-autoimmune-diseases-mechanisms-and-risk-factors
  42. Kline, C. E. (2014). The bidirectional relationship between exercise and sleep. American Journal of Lifestyle Medicine, 8(6), 375–379. https://doi.org/10.1177/1559827614544437
  43. Koren, O., Goodrich, J. K., Cullender, T. C., Spor, A., Laitinen, K., Kling Bäckhed, H., Gonzalez, A., Werner, J. J., Angenent, L. T., Knight, R., Bäckhed, F., Isolauri, E., Salminen, S., & Ley, R. E. (2012). Host remodeling of the gut microbiome and metabolic changes during pregnancy. Cell, 150(3), 470–480. https://doi.org/10.1016/j.cell.2012.07.008
  44. Leproult, R., & Van Cauter, E. (2009). Role of sleep and sleep loss in hormonal release and metabolism. Pediatric Neuroendocrinology, 11–21. https://doi.org/10.1159/000262524
  45. MacLean, C. R. K., Walton, K. G., Wenneberg, S. R., Levitsky, D. K., Mandarino, J. P., Waziri, R., Hillis, S. L., & Schneider, R. H. (1997). Effects of the transcendental meditation program on adaptive mechanisms: Changes in hormone levels and responses to stress after 4 months of practice. Psychoneuroendocrinology, 22(4), 277–295. https://doi.org/10.1016/s0306-4530(97)00003-6
  46. Magata, F., Tsukamura, H., & Matsuda, F. (2023). The impact of inflammatory stress on hypothalamic kisspeptin neurons: Mechanisms underlying inflammation-associated infertility in humans and domestic animals. Peptides, 162, 170958. https://doi.org/10.1016/j.peptides.2023.170958
  47. Maholy, N. (2023, May 10). A Functional Medicine Immune Support Protocol. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-immune-support-protocol
  48. Maholy, N. (2023, May 23). A functional medicine treatment protocol for metabolic syndrome: Testing, nutrition, and supplements. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-treatment-protocol-for-metabolic-syndrome-testing-nutrition-and-supplements
  49. Mikulska, P., Malinowska, M., Ignacyk, M., Szustowski, P., Nowak, J., Pesta, K., Szeląg, M., Szklanny, D., Judasz, E., Kaczmarek, G., Ejiohuo, O. P., Paczkowska-Walendowska, M., Gościniak, A., & Cielecka-Piontek, J. (2023). Ashwagandha (Withania Somnifera)—current research on the health-promoting activities: A narrative review. Pharmaceutics, 15(4), 1057. https://doi.org/10.3390/pharmaceutics15041057
  50. Mishra, S. (2013). Effect of physical activity on insulin resistance, inflammation and oxidative stress in diabetes mellitus. Journal Of Clinical And Diagnostic Research. https://doi.org/10.7860/jcdr/2013/6518.3306
  51. Monda, V., Villano, I., Messina, A., Valenzano, A., Esposito, T., Moscatelli, F., Viggiano, A., Cibelli, G., Chieffi, S., Monda, M., & Messina, G. (2017). Exercise modifies the gut microbiota with positive health effects. Oxidative Medicine and Cellular Longevity, 2017, 1–8. https://doi.org/10.1155/2017/3831972
  52. Moulton, V. R. (2018). Sex hormones in acquired immunity and autoimmune disease. Frontiers in Immunology, 9. https://doi.org/10.3389/fimmu.2018.02279 
  53. Mörbe, U., Jørgensen, P., Fenton, T., von Burg, N., Riis, L., Spencer, J., & Agace, W. (2021). Human gut-associated lymphoid tissues (galt); diversity, structure, and function. Mucosal Immunology, 14(4), 793–802. https://doi.org/10.1038/s41385-021-00389-4
  54. Nagpal, R., Shively, C. A., Register, T. C., Craft, S., & Yadav, H. (2019). Gut microbiome-mediterranean diet interactions in improving host health. F1000Research, 8, 699. https://doi.org/10.12688/f1000research.18992.1
  55. Niewiem, M., & Grzybowska-Chlebowczyk, U. (2022). Intestinal barrier permeability in allergic diseases. Nutrients, 14(9), 1893. https://doi.org/10.3390/nu14091893
  56. Peters, B., Santoro, N., Kaplan, R., & Qi, Q. (2022). Spotlight on the gut microbiome in menopause: Current insights. International Journal of Women’s Health, Volume 14, 1059–1072. https://doi.org/10.2147/ijwh.s340491
  57. Powha, R., Goyal, A., & Jialal, I. (2023). Chronic Inflammation. In StatPearls. essay, StatPearls Publishing.
  58. Preston, J. (2023, October 3). A functional medicine protocol for seasonal allergiesJ. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-protocol-for-seasonal-allergies
  59. Rusch, J. A., Layden, B. T., & Dugas, L. R. (2023). Signalling cognition: The gut microbiota and hypothalamic-pituitary-adrenal axis. Frontiers in Endocrinology, 14. https://doi.org/10.3389/fendo.2023.1130689
  60. Salles, B. I., Cioffi, D., & Ferreira, S. R. (2020). Probiotics supplementation and Insulin Resistance: A systematic review. Diabetology & Metabolic Syndrome, 12(1). https://doi.org/10.1186/s13098-020-00603-6
  61. Salve, J., Pate, S., Debnath, K., & Langade, D. (2019). Adaptogenic and anxiolytic effects of ashwagandha root extract in healthy adults: A double-blind, randomized, placebo-controlled clinical study. Cureus. https://doi.org/10.7759/cureus.6466
  62. Sanders, K. M., Koh, S. D., Ro, S., & Ward, S. M. (2012). Regulation of gastrointestinal motility—insights from smooth muscle biology. Nature Reviews Gastroenterology & Hepatology, 9(11), 633–645. https://doi.org/10.1038/nrgastro.2012.168
  63. Silva, Y. P., Bernardi, A., & Frozza, R. L. (2020). The role of short-chain fatty acids from gut microbiota in gut-brain communication. Frontiers in Endocrinology, 11. https://doi.org/10.3389/fendo.2020.00025
  64. Smith, R. P., Easson, C., Lyle, S. M., Kapoor, R., Donnelly, C. P., Davidson, E. J., Parikh, E., Lopez, J. V., & Tartar, J. L. (2019). Gut microbiome diversity is associated with sleep physiology in humans. PLOS ONE, 14(10). https://doi.org/10.1371/journal.pone.0222394
  65. Sundaresan, B., Shirafkan, F., Ripperger, K., & Rattay, K. (2023). The role of viral infections in the onset of autoimmune diseases. Viruses, 15(3), 782. https://doi.org/10.3390/v15030782
  66. Teeter, L. A. (2023, April 13). Using functional nutrition to address hormone imbalances. Rupa Health. https://www.rupahealth.com/post/using-functional-nutrition-to-address-hormone-imbalances
  67. Tharakan, A., Shukla, H., Benny, I. R., Tharakan, M., George, L., & Koshy, S. (2021). Immunomodulatory effect of Withania somnifera (ashwagandha) extract—a randomized, double-blind, placebo controlled trial with an open label extension on Healthy Participants. Journal of Clinical Medicine, 10(16), 3644. https://doi.org/10.3390/jcm10163644
  68. Vanuytsel, T., van Wanrooy, S., Vanheel, H., Vanormelingen, C., Verschueren, S., Houben, E., Salim Rasoel, S., Tόth, J., Holvoet, L., Farré, R., Van Oudenhove, L., Boeckxstaens, G., Verbeke, K., & Tack, J. (2013). Psychological stress and corticotropin-releasing hormone increase intestinal permeability in humans by a mast cell-dependent mechanism. Gut, 63(8), 1293–1299. https://doi.org/10.1136/gutjnl-2013-305690
  69. Velez, L. M., Seldin, M., & Motta, A. B. (2021). Inflammation and reproductive function in women with polycystic ovary syndrome. Biology of Reproduction, 104(6), 1205–1217. https://doi.org/10.1093/biolre/ioab050
  70. Weinberg, J. L. (2022, September 7). An integrative medicine approach to hypothyroidism. Rupa Health. https://www.rupahealth.com/post/understanding-hypothyroidism-and-how-to-treat-it-naturally
  71. Weinberg, J. L. (2022, November 16). 4 science backed health benefits of the Mediterranean diet. Rupa Health. https://www.rupahealth.com/post/4-science-backed-health-benefits-of-the-mediterranean-diet#:~:text=A%20Mediterranean%20diet%2C%20emphasizing%20vegetables,fatty%20liver%20disease%20(NAFLD).
  72. Weinberg, J. L. (2023, May 12). How to tell if you have an estrogen imbalance. Rupa Health. https://www.rupahealth.com/post/a-functional-medicine-approach-to-estrogen-imbalance
  73. Wiertsema, S. P., van Bergenhenegouwen, J., Garssen, J., & Knippels, L. M. (2021). The interplay between the gut microbiome and the immune system in the context of infectious diseases throughout life and the role of Nutrition in Optimizing Treatment Strategies. Nutrients, 13(3), 886. https://doi.org/10.3390/nu13030886
  74. Yan, F., & Polk, D. B. (2011). Probiotics and immune health. Current Opinion in Gastroenterology, 27(6), 496–501. https://doi.org/10.1097/mog.0b013e32834baa4d
  75. Yaylali, O., Kirac, S., Yilmaz, M., Akin, F., Yuksel, D., Demirkan, N., & Akdag, B. (2009). Does hypothyroidism affect gastrointestinal motility? Gastroenterology Research and Practice, 2009, 1–7. https://doi.org/10.1155/2009/529802 
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