Fungal Overgrowth Blues: are you really hosting fungal overgrowth? Here is what you should know.

Fungal overgrowth is a common diagnosis, but often, the problem is more complex. Take the approach of Functional Medicine Australia.

The human gastrointestinal tract or gut is home to trillions of microorganisms, collectively known as the gut microbiota. These microbial inhabitants include hundreds of species of bacteria, fungi, viruses, archaea and protozoa1. In healthy people, these diverse microbial communities thrive in perfect equilibrium, with bacteria representing the most abundant group. However, when this equilibrium is broken, alterations to your optimal gut function can occur, including gut dysbiosis and Small Intestinal Bacterial Overgrowth (SIBO), which can lead to multiple health problems. Functional Medicine Australia takes a new approach to health, considering your health as well as the health of your gut microbes, based on comprehensive advanced testing.


Gut Dysbiosis


Alterations to the normal composition and diversity of gut microbes can result in gut dysbiosis, where specific microbial species are depleted, whereas others are over-represented. Another related condition is SIBO where the overgrowth occurs in the small intestine.

Gut dysbiosis and SIBO have been linked to multiple health problems, including dysregulation of the immune system, causing abnormal inflammatory responses. Such inflammatory alterations can contribute to the development of chronic inflammatory conditions, like inflammatory bowel disease, multiple sclerosis, allergic asthma, and rheumatoid arthritis2-6. Conditions like cystic fibrosis and fungal overgrowth are also associated with gut dysbiosis6-7.

Gut dysbiosis and SIBO occur when there is an overgrowth of normally harmless microbes, which can lead to disease or can facilitate infection by external pathogens, like fungi. Learn more about the gut microbiome and your health here. Functional Medicine Australia takes a modern approach to your health, taking into account the health of your gut mycobiome, among many other factors.



Focus on: the human mycobiome


The human mycobiome is the name given to the community of fungal species inhabiting our skin, mouth, and inner organs. Fungi are an ancient group of organisms that include the well-known mushrooms, but also yeasts (like those used to make beer or bread) and moulds (like those that grow on old bread). Fungi are found everywhere in nature, as free-living organisms but also as parasitic or infectious agents, living on or inside plants or animals, including humans.

In humans, more than a hundred different species of fungi have been reported to live in different parts of the body (Figure 2).


There is also a rich diversity of fungi among different people. For example, one study that compared the oral fungal diversity among 20 healthy persons identified 101 fungal species among all participants10. However, each person only hosted between 9-23 fungal species in their mouth, showing that there is a large diversity of fungi among humans. Another study, which generated data for 317 stool samples from the Human Microbiome Project, found that the human gut is dominated by yeast belonging to the Saccharomyces, Malassezia, and Candida genera15.

These fungal species live alongside our gut, skin and oral bacteria, as well as alongside all the other microorganisms that constitute our body’s microbiota. In health, all these microbial groups live in balance and harmony, with bacteria representing the dominating group, limiting the growth of other groups. However, when gut dysbiosis occurs, this balance is broken and overgrowth by potentially pathogenic fungal species can occur. In fact, fungal overgrowth and fungal infections are common conditions that are associated with a wide range of conditions, including digestive problems, changes in mood, headaches, skin problems, immune malfunction, fatigue and weight gain, among other health problems6.


Fungal overgrowth and infections in Australia


One of the most common fungal infections affecting Australians involves yeast infections by the genus Candida. Candidais a fungus commonly found as part of the normal, healthy microbiota of the mouth, gut and genitals, in both males and females. But, under certain circumstances, Candida yeast overgrowth can lead to a disease called candidiasis. Some fungal Candida-related infections, like vaginal thrush, affects as many as 75% of all Australian women.


What is Candidiasis?


Candidiasis is a common yeast infection caused by an overgrowth of the yeast Candida. It is not a sexually transmitted disease, as it is exclusively caused by fungal overgrowth. While Candida is a common inhabitant of your oral cavity, gut and genitals if it overgrows it can cause health problems. The most common species causing candidiasis in adults is Candida albicans, whereas Candida parapsilosis is a species that mostly affects babies and transplant patients. Although less common, Candida parapsilosis is another species known to affect adults8-9.

      • Typical symptoms – depending on the site where the Candida outgrow occurs, people suffering from candidiasis can experience multiple symptoms. For example,


            • Genital candidiasis – also known as genital thrush, can cause redness and swelling of the vagina, a burning, itching or stinging sensation, pain during sex or urination, and is typically accompanied by vaginal discharge with a strong “yeasty” smell. This condition can also affect males, causing similar symptoms as in women. Male genital thrush causes soreness and redness in the penis head, smelly discharges and pain when urinating.


            • Oral candidiasis – also known as oral thrush, this condition is characterised by taste loss, pain while eating or swallowing, and white patches and soreness in the inside of the mouth. Oral candidiasis is not limited to the mouth, it can also extend to the throat and oesophagus. Candidiasis of the oesophagus is a common condition in people living with HIV/AIDS or with a compromised immune system. Typical symptoms include pain/difficulty swallowing, nausea, vomiting, chest pain and weight loss.


            • Candidiasis in the gut – various factors can lead to the overgrowth of gut fungal species such as Candida, which can potentially affect various aspects of your health. For example, overgrowth of Candida in the gut is associated with multiple diseases of the gut, like ulcerative colitis, Crohn’s disease, gastric ulcers and reduced inflammatory responses16. Typical symptoms depend on the specific disease but may include bloody diarrhea, abdominal pain and cramping, weight loss, fatigue, fever, reduced appetite, or vomiting.


            • Invasive candidiasis – this serious condition occurs when the Candida species manages to invade the bloodstream, infecting organs like the kidney, heart bones, eyes, and even the brain. This condition is more common in hospitalised patients or in people who are already suffering from other conditions. Typical symptoms vary, depending on the site of infection and may include dysphagia, skin or mucosal lesions, blindness, vaginal symptoms (itching, burning, discharge), fever, shock, oliguria, renal shutdown, and others.


      • Factors triggering Candida overgrowth – Several factors are known to influence the overgrowth of Candida. Below we discuss some of the most important factors.


            • Antibiotic use – long-term antibiotic use drastically changes the composition of gut microbiota in mice, favouring the presence of fungal species17-18


            • Certain conditions can favour the development of candidiasis, like being pregnant or suffering from certain diseases, like diabetes or a compromised immune system19-23


            • Hormonal contraceptives have been associated with Candida outgrowth24.


            • Early-life factors – anything from your mode of delivery (C-section vs natural birth) to the lifestyle of your mother and your early feeding habits (e.g. being breastfed) can influence your chances of developing fungal overgrowth25-26.


            • Immune dysfunction, which can be caused by genetic malfunctions or exposure to environmental toxins, among other factors27.


            • Unhealthy eating habits – following a diet rich in carbohydrates and sugar, for example, can favour yeast growth28.


            • Chronic stress – studies have shown that chronic stress is among the factors that can predispose women to develop vaginal candidiasis29.


            • Use if certain medicines, like corticosteroids, oral contraceptives or certain prescription drugs30-31


Do you suffer from fungal overgrowth?


Today, a significant proportion of patients in primary care are misdiagnosed with fungal overgrowth and prescribed a treatment plan that can worsen their condition. This is a problem because often patients may be suffering from other health problems, like SIBO, in addition to fungal overgrowth or might not even have fungal overgrowth at all.


Fungal overgrowth testing is crucial


Accurate and comprehensive testing is critical to confirm fungal overgrowth and to rule out any other potential health problems. Only after the results of comprehensive testing have been analysed, a treatment plan can be envisioned.

Our model of Modern functional medicine Australia relies on comprehensive testing and interpretation before any treatment plan is developed.

Our approach of Modern Functional Medicine Australia employs the following testing:


      • Advanced stool analysis

        here we employ a complete microbiome mapping approach, called GI-MAP, which currently stands as the most advanced DNA-based stool test available in Australia. This comprehensive test can identify the microbial diversity of your gut and identify if you have any worrisome levels of pathogens, including yeast and other microbes that can cause disease. This test will also measure the levels of multiple health markers, like specific enzymes, fat and blood content in stool, and confirm the presence of genes involved with antibiotic resistance. Read more about our testing here.


      • Organic Acid Testing

        this is a urine test that can detect a wide range of important biological markers of health. These markers can inform us about how well your metabolism is working and how well cells are functioning. It can also inform us about your levels of vitamins and other important chemicals, like neurotransmitters or about the presence of toxins. Learn more about our Organic Acid Testing here.


      • Immunological testing

        this test allows for the identification of biological markers that can inform us about the presence of Candida yeast infection in the blood. This would be indicative of a serious systemic yeast infection.



Modern Functional Medicine Australia: a better approach to fungal overgrowth


At the Australian Centre for Functional Medicine, we take a comprehensive approach for testing and treating fungal infections. We take into consideration your current symptoms and consider the possibility of fungal overgrowth, but we are mindful about the wide range of other possible conditions that can affect you.

We rely on our extensive testing panels, which analyse your blood, stool, urine, and breath and provide critical information about every aspect of your body function and health status. Once we have analysed your test results, we can develop a treatment plan, which can include different approaches, from standard care treatments (antibiotics, or other drugs) to natural and preventive approaches.

For all patients, a new nutritional plan is designed based on their personal needs and requirements. Following the design of a nutritional plan, we follow a two-phase approach; First, removal of the pathogen, in case of infection, or clearing the fungal overgrowth. Once your body is clear from the infection or overgrowth, we can start the second phase, focused on rebuilding and restoring your gut microbiome and nutrient status.

If you suspect a yeast infection is affecting your health, become a patient today and learn about all the factors that might be at play.




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