A healthy gut is a pivot for good coordination of all activities in the body including gastrointestinal activities, immune system, drug metabolism, physical, and mental health, and even hormonal balance.
The gut microbiome constitutes the entire population of microorganisms that colonizes a particular location, and it includes not just bacteria, but other microbes also such as fungi, viruses, and archaea.
It helps manage a variety of health conditions ranging from inflammatory bowel diseases, obesity, and diabetes, allergic disease to neural illnesses.
Recently, few studies have reported its impact on the female reproductive system and related conditions.
The imbalanced gut microbiota can trigger several diseases and conditions in females, including complications during pregnancy, adverse pregnancy outcomes, PCOS, endometriosis, and even cancer.
The gut microbiota exhibit an essential role in the reproductive endocrine system in a female’s life by interacting with female sex hormones; estrogen, androgens, and insulin. Estrogen is the female sex hormone that regulates the menstrual cycle. It is not only influenced by estrogen levels but it also actively affects estrogen levels. The Gut microbiota that is capable of regulating estrogen levels is estrobolome.
How Gut Microbiota Regulates Female Sex Hormone Estrogen?
The gut microbiota helps to regulate estrogen levels by secretion of β-glucuronidase, an enzyme that breaks down estrogen in the gastrointestinal tract. This estrogen is forwarded to the uterus via the bloodstream where it binds to estrogen receptors, resulting in physiological downstream effects.
A decrease in β-glucuronidase activity as a result of gut microbial dysbiosis can result in the reduced breakdown of estrogen and low circulating estrogens in the bloodstream.
This alters the activation of estrogen receptors leading to health conditions such as obesity and cardiovascular diseases and even cognitive decline.
On the other hand, increased β-glucuronidase activity can result in elevated estrogen levels in the blood leading to health conditions, such as endometriosis and cancer. Thus, optimal microbiome activity is essential to maintain estrogen levels in females.
In addition, estrogen levels can also affect PCOS, endometrial hyperplasia, and ultimately fertility.
How Gut Microbiota Regulates PCOS?
PCOS is an endocrine disorder that leads to difficult pregnancies or infertility in about 6.5−8.0% of reproductive-age women.
The syndrome is characterized by hyperandrogenism (that regulates male characteristics), amenorrhoea ( absence of menstruation), and polycystic ovary.
In addition, the gut microbiome contributes to several additional characteristics of PCOS such as obesity, hyperandrogenism, insulin resistance, and low-grade inflammation, therefore indirectly participating in the onset of PCOS.
In a study, Escherichia coli, a bacteria found in the gut in abundance, showed a positive relationship with serum luteinizing hormone (LH) levels and follicle-stimulating hormone (FSH), and a higher level of these hormones are linked with PCOS condition in females.1
In another study, the gut microbiome is directly related to Ghrelin, the hormone that initiates hunger. It is found that during PCOS, ghrelin levels are low whereas BMI and testosterone levels are high. Therefore imbalanced gut microbe is the indirect risk factor for PCOS.
An increase Escherichia and Shigella in PCOS can also alter the synthesis of the short fatty acids chain that is beneficial to regulate lipid profile in the body.2
Dietary Intervention to Correct Gut Dysbiosis
The following dietary interventions can help promote good bacterial and eliminate harmful bacteria from the gut to improve PCOS symptoms:
- Regarding carbohydrates, it is suggested that high levels of glucose, fructose, and sucrose in diet, increase Bifidobacteria (good bacteria) and reduce Bacteroides (bad bacteria).
- Besides, non-digestible carbohydrates, such as whole grain and wheat bran, increase Bifidobacteria and Lactobacilli (good bacterias).
- Regarding protein, it is recommended that a high intake of animal-based proteins increase the count of bacterial species of Bacteroides, Alistipes, and Bilophil (bad bacteria), and reduce counts of Bifidobacterium (good bacteria) that increase the risk of cardiovascular disease.
- On the contrary, plant proteins increase the count of Bifidobacterium and Lactobacillus (good bacteria), and reduce the count of Bacteroides and Clostridium (bad bacteria), with the positive health outcome of increasing Short Chain Fatty Acids levels that eventually reduce inflammation.3
- Regarding fats, it is recommended that a high-fat diet increases the count of Bacteroides (bad bacteria) and reduces the count of Lactobacillus (good bacteria) which results in increased inflammation.
- Incorporating probiotics into the diet is reported to exhibit positive effects on the metabolic profile in women with PCOS.
- Probiotic supplementation including the bacterial species of L. acidophilus, L. casei, and B. bifidum (good bacterias) for 12 weeks are reported to reduce weight and BMI significantly in PCOS patients and simultaneous reduction in glycemic index, triglycerides, and VLDL cholesterol.
- Prebiotics supplementation with, fructooligosaccharides (FOS), inulin, galactooligosaccharides (GOS), and lactulose, the most common ones, induce the growth of both Bifidobacterium and Lactobacillus (good bacterias), which helps in reduction of fasting glucose, triglycerides, total cholesterol, and bad cholesterol, with a significant increase in good cholesterol levels.
- Dietary fiber also plays a beneficial role in the composition of the gut microbiota where it acts as a prebiotic to support useful gut bacteria and suppresses harmful bacteria.
PCOS is a very common reproductive disorder in females of reproductive age and is characterized by irregular menstruation, weight gain around the abdomen, excessive hair growth, and acne skin.
Current research well establishes that an imbalanced gut microbiome is linked to several female reproductive tract disorders, commonly endometriosis, PCOS, gynecological cancers, and infertility.
The imbalance in gut flora or dysbiosis of gut microbiota brought about by an unhealthy diet is responsible for an increase in gut mucosal permeability, releasing lipopolysaccharides in blood, activating the immune system, increasing serum insulin levels, leading to increased androgen production in the ovary that interferes with normal follicular development during PCOS.
However, an appropriate dietary intervention is recommended to enhance the count of good bacteria and decrease the count of harmful bacteria in the gut will eventually help to improve lipid profile, balance hormones, eliminate bad cholesterol and promote good cholesterol with significant weight loss.
The supplementation with prebiotics and probiotic is highly recommended to promote good bacteria in women with PCOS.
Get a healthy diet plan for yourself to incorporate good bacteria in your gut to improve PCOS and related symptoms.