by Mila McManus, MD
Perhaps one of the greatest errors from a medical perspective has been to specialize and compartmentalize the human body for diagnosis and treatment. The last 25 years of research have demonstrated the need for a bigger, more comprehensive understanding of hormone balance, given the integrated and complex interplay between the gut, brain, and endocrine organs.
The word endocrine means relating to glands that secrete hormones. The field of endocrinology, which studies the endocrine system and hormones, was formally established in 1916 with the creation of the Association for the Study of Internal Secretions. The system group of glands has traditionally included the hypothalamus, pituitary, thyroid, parathyroid, adrenals, pancreas, testes [males], and ovaries [females]. Over 100 years later, our understanding of hormones has become much better, and is no longer limited to the original organs considered as part of the endocrine system. The gut could well be considered an endocrine organ. There are more than 50 identified hormones in the human body which function in complex and integrated ways with one another and with other organ systems. It should put into question seeing an endocrinologist who knows little about gut or brain function, or a gastroenterologist who knows little about endocrine or brain function, or a neurologist who understands little about the gut or endocrine system.
The Problems of Hormone Imbalance
Hormone imbalances lead to all kinds of misery for men and women. Women see hormone imbalances play out with Polycystic Ovary Syndrome [PCOS], perimenopause, menopause, irregular or absent periods, premenstrual syndrome, and thyroid disorders. Men experience hormonal imbalances that are diagnosed as low testosterone, enlarged breast tissue (gynecomastia), thyroid disorders, erectile dysfunction, and high cortisol levels [Cushing’s syndrome]. Adults and young adults are getting diabetes, thyroid disorders, acne, adrenal insufficiency, and high cortisol levels in unprecedented numbers.
The Bigger Understanding
Hormone balance is dependent on a healthy interplay between the gut, the brain, and the endocrine system. It’s apparent that we cannot isolate a single part of the human body and understand it completely, especially as it relates to other parts of the body. It’s complicated! Let’s examine several fascinating and clinically important relationships that integrative practitioners consider when assessing hormone imbalances.
- The gut is really an endocrine [hormone-producing] organ. Not only is the gut responsible for digestion, but it is also a major hormone-producing organ. Enteroendocrine cells line the GI tract and secrete more than 20 different hormones influencing metabolism, appetite, mood, and reproductive health. GLP-1 is one such example, which improves insulin sensitivity and satiety. Ghrelin is a hormone that stimulates hunger and rises before meals. Fullness is signaled by the hormones PYY and CCK. Serotonin [5-HT], of which 90-95% is made in the gut, affects mood and bowel motility. An inflammatory gut condition will negatively affect all of these functions.
- Thyroid, adrenal, and sex hormone function for both men and women are downstream from gut function. Inflamed or imbalanced gut activity causes a ripple effect through the entire endocrine system. The gut microbiota helps to regulate estrogen metabolism. Dysbiosis in the gut can lead to estrogen dominance or deficiency. Leaky gut increases systemic inflammation and can suppress thyroid, adrenal, and sex hormone function. The liver and gut work together to clear hormones through detoxification pathways. If constipation or poor bile flow is present, hormones are reabsorbed instead of being excreted. Nutrient absorption in the gut also affects hormone synthesis and receptor sensitivity, particularly with B vitamins, zinc, and magnesium.
- Conversely, hormones can alter gut motility, microbiome diversity, and barrier function. Estrogen supports the mucosal integrity of the gut as well as microbiome diversity. Low estrogen [e.g., menopause] can lead to constipation or dysbiosis. Progesterone can be responsible for slowing GI motility, especially during certain phases of the menstrual cycle or during pregnancy. Cortisol, secreted during chronic stress, reduces digestive enzyme output and increases gut permeability. Finally, thyroid hormones directly regulate gut motility; hypothyroidism commonly causes constipation.
Systemic Inflammation Suppresses Hormone Function
As you can see, with a deeper understanding of hormone balance, every source of inflammation can have a negative impact on it. Normally, internal injury causes the release of chemical messengers called cytokines, which are meant to facilitate healing. However, when considerable inflammation and dysfunction exist, leading to chronic, ongoing inflammation, cytokines begin to interfere with the body’s hormone communication network. The brain’s control centers [the hypothalamus and pituitary] become less responsive, so signals to the thyroid, adrenals, and reproductive glands weaken. The result? Fatigue, low libido, menstrual irregularities, sluggish metabolism, and mood swings – even when your lab numbers look “normal”.
Inflammation also changes the way hormones are processed. It can block the conversion of thyroid hormone [T4] into its active form [T3], promote the conversion of testosterone into estrogen, and blunt the sensitivity of hormone receptors at the cellular level. In short, your body may make hormones, but your cells can’t “hear” them.
Taking Your Bigger Understanding and Putting It to Use
Understanding the integrated and complex interplay between the gut, brain, and endocrine organs helps explain why many people experience symptoms of hormonal imbalance without clear answers from conventional labs and practitioners. The problem often isn’t a lack of hormones, but rather inflammatory interference that prevents proper function. Addressing inflammation can often restore balance naturally, reducing the need for constant hormone adjustments.
Bottom line: If your hormones feel “off”, it may not be your age or your glands – it could be the silent fire of inflammation. Calming that fire is often the missing key to true hormonal balance. We can help extinguish the fire! Let us take an integrated look at your health.
Get the Bigger Understanding. Be Well.
References
- Cani, P.D., et al. Metabolic Endotoxemia Initiates Obesity and Insulin Resistance. Diabetes (2007).
- Ervin, S.M., et al. Gut Microbial β-Glucuronidase and Estrogen Reactivation. Frontiers in Cellular and Infection Microbiology (2019).
- Rusch, J.A., et al. Gut Microbiota and Hypothalamic–Pituitary Interactions. Endocrine Reviews (2021).
- Sun, L.J., et al. Gut Hormones in Microbiota–Gut–Brain Cross-Talk. Frontiers in Endocrinology (2018).
- Mohammad, S., et al. Role of Metabolic Endotoxemia in Systemic Inflammation and Disease. International Journal of Molecular Sciences (2021).