by Jenny Lelwica Buttaccio
If you’ve been in holistic health or chronic illness circles for any length of time, you’ve probably bore witness to the panic that ensues at the very mention of the word “candida.” But just what is it about this microbe that causes a particular stir among people? And, what role does it play in contributing to the health challenges so many of us struggle with?
Here, we aim to answer your most pressing questions about candida so that you can implement any changes you may need to improve your health.
What is Candida, Anyway?
Candida is a type of yeast — a single-cell microorganism — that normally takes up residence in various niches in the body such as the skin, mouth, intestinal tract, and vagina. “Candida has to have a host to survive, and it’s commensal,” says Dr. Bill Rawls, Medical Director of Vital Plan, meaning it’s opportunistic and benefits from its association with other organisms.
This is compared to the mutualistic relationship we have with our normal flora that’s been honed for millions and millions of years, explains Dr. Rawls, where the microbes are taking advantage of us, but we have also learned to take advantage of them.
For instance, there are numerous bacteria in our digestive tract that, in exchange for being well fed, aid with nutrient metabolism, vitamin production, and waste processing. Candida is an exception when it comes to providing advantages: It does nothing that we know of to support or improve our overall health and well-being.
Candida belongs to the kingdom of organisms known as fungi, which also includes mushrooms, mold, mildew, and more. Along with a spectrum of different types of microbes, everyone has some amount of candida in their gut. If you’re a healthy individual, other microorganisms that make up your body’s unique flora (the total sum of which is called your microbiome), such as bacterial constituents Lactobacillus acidophilus and Bifidobacterium bifidum, work synergistically to maintain a balance with one another so that one or more don’t become problematic to your health.
Currently, there are more than 20 known species of candida that cause infections or yeast overgrowth in humans, according to the Centers for Disease Control and Prevention (CDC). The most common type to affect humans is known as Candida albicans (C. albicans).
You may already be familiar with the more common types of candida overgrowth like oral thrush (often seen in babies and older adults) or vaginal yeast infections. Generally, a candida infection isn’t life-threatening, though it may make you feel lousy. But if overgrowth remains untreated, it can spread to the bloodstream, causing a serious infection called invasive candidiasis, which can affect the blood, certain organs, bones, and more, states the CDC.
Symptoms of Candida Overgrowth
The symptoms of a candida infection can range from mild to severe, and they vary from person to person. For instance, one person may experience bloating and nothing else; another may struggle with every possible side effect. Candida overgrowth symptoms include any number of the following:
- Oral thrush (characterized by creamy white bumps on the inner cheeks and tongue)
- Recurring vaginal yeast infections
- Chronic urinary tract infections (UTIs)
- Unrelenting fatigue or chronic fatigue syndrome (CFS)
- Bowel disorders such as Crohn’s disease and ulcerative colitis
- Gastric ulcers
- Digestive issues (gas, bloating, constipation, diarrhea)
- Abdominal pain and cramping
- Sugar and carbohydrate cravings
- Joint pain and muscle aches
- Anxiety and depression
- Mood swings and irritability
- Recurring sinus infections
- Chronic inflammation
- Brain fog
- Poor sleep
If you’re thinking that sounds like a long laundry list of symptoms that could easily be confused with a number of other health problems, you’re right. What’s more, candida infections rarely exist by themselves, says Dr. Rawls. Most likely, if you have an overgrowth of the yeast, you also have an excess of other opportunistic microbes in the gut, and it can be difficult to differentiate between them.
The Primary Causes
If we all carry some candida in our body, why do some of us experience overgrowth and miserable symptoms, but the rest of us never know the fungus is even present? Here are the common underlying causes for candida infection.
1. Impaired immune function
For candida overgrowth to occur, you must experience a disruption in your immune system, Dr. Rawls notes. We are regularly exposed to microbes that can make us sick, but often our good flora are able to keep those pathogens in check.
“It’s the balance of the microbiome that we’re finding is so important to disease,” says Dr. Rawls. “And candida overgrowth, in particular, is a symptom of someone’s immune system being trashed, and their microbiome being disturbed — which is not in itself, an illness.”
Underlying immune dysfunction can be a result of chronic illness (including chronic Lyme disease, fibromyalgia, and chronic fatigue syndrome) or any immune-weakening disease or condition. A number of lifestyle factors may also be at play, including lack of sleep, chronic stress, and inactivity—all of which can hamper immune function and upset your body’s balance of flora.
2. Gut dysfunction
In addition to immune system dysfunction, candida overgrowth is typically preceded by a breakdown in your gut health, and microbiome imbalance is soon to follow. Conditions such as leaky gut syndrome, irritable bowel syndrome, and gluten intolerance often coincide with candida overgrowth. Chronic stress is a top culprit, as is consuming excessive refined carbohydrates (candida thrive on starch—more on that below).
3. Antibiotic use
One way the gut flora can be disrupted is through the use of antibiotics, such as when treating Lyme disease and common co-infections like mycoplasma and bartonella. Antibiotics target bacteria – including the ones that are helpful to your body. Researchers discovered that when antibiotics kill off various beneficial bacterial species in the gut, the balance of microbes that normally keeps candida in check begins to shift. This creates favorable conditions for fungal communities to thrive, and can set the stage for candida overgrowth, as stated in the journal, Trends in Microbiology.
4. A carb-loaded diet
To compound the problem, says Dr. Rawls, the diet most common in modern Western society – excess carbohydrates, refined grains, and saturated fats, and minimal fresh produce, lean protein, and healthy fats – is neither natural nor nourishing to our bodies. The reason sugar and refined carbohydrates get a bad rap is that they act as fuel sources for candida. When you feed candida, you facilitate overgrowth and microbiome disruption, which further disrupts the immune system and impairs its ability to maintain a symbiotic relationship with numerous other microbes.
5. Environmental toxins
Another cause of yeast overgrowth includes exposure to environmental and chemical toxins. A prime example of an environmental toxin is mold. All houses have some mold inside of them, about half of which are at problematic levels. Both mold spores and mold metabolites, known as mycotoxins, are present in the air. When inhaled, they can suppress your immune system and allow candida overgrowth, explains Dr. Rawls. Plus, candida itself can produce its own mycotoxins that make you miserable.
Regarding chemical toxins, Dr. Rawls suggests that people are often unaware of the barrage of hidden, chemical exposures present in homes and the environment, which can contribute to hormone imbalances, and ultimately, immunosuppression. Top sneaky toxins found in homes include:
- Phthalates, endocrine-disrupting chemicals used to make plastics flexible
- Bisphenol A, another endocrine-disruptor found in food and drink containers, can linings, and receipts
- Formaldehyde, often found in building materials and pressed-wood furniture products
- Radon, an odorless, radioactive gas that can seep into homes from the ground
- Parabens, estrogen imitators used in cosmetics and other beauty products
- Chlorine, a disinfectant used in municipal water systems
- Perfluorochemicals (PFCs), used on stain-resistant fabrics (Scotchgard, Goretex), cooking pans (Teflon), food wrappers, and microwave popcorn bags
- Flame retardants in building materials, cushions, and more
- Lead in paint made prior to 1978 and old plumbing
Testing and Diagnosis
In many cases, candida overgrowth can be assumed based on an assessment of your symptoms and a risk factor analysis—no separate candida-focused testing needed, says Dr. Rawls.
But in severe cases where symptoms are persistent and life-disrupting, there might be a need to gather additional medical information, such as the strain or species of yeast you’re trying to combat. Other people simply feel more comfortable with an official diagnosis. In those instances, work with your doctor to determine whether the following tests may be appropriate:
There are a variety of specialty labs offering a comprehensive stool analysis, which checks for the strain and species of yeasts that reside in your gut. They can tell you whether your candida levels fall within the normal range (though not what might be a normal for your particular microbiome).
Blood Antibody Testing
Blood work examines the IgG, IgM, and IgA antibody levels of candida. Elevated antibody levels can indicate a candida overgrowth somewhere in the body. But similar to antibody tests that check for Lyme disease, it’s possible to get a false negative. That’s because when candida suppresses the immune system, your body may not be able to yield a sufficient response and produce measurable levels of antibodies for the test.
Urine Organic Acids Testing
If an overgrowth of candida is present in the gut, it creates a metabolite known as D-Arabinitol, which will be excreted in the urine as a byproduct.
Complete Blood Count (CBC) with Differential
Another way to assess immune function, a CBC can detect a low white blood cell count, which has been associated with yeast overgrowth. But it’s important to note that results are very non-specific, says Dr. Rawls. A low white blood cell count could indicate any number of other illnesses, so a CBC test alone will not help you pinpoint candida infection.
This detects the DNA of certain specific candida species. A negative test indicates that either the species-specific DNA is not present, or that levels are present at a concentration below the detectable limit.
It’s important to note that no testing methods provide a foolproof way to detect the presence of candida overgrowth. Positive test results or no, if you suspect you’re suffering from yeast overgrowth, treatment aimed at restoring immune and gut health and balancing the microbiome will address yeast overgrowth along with too-high levels of other problematic microbes and related health concerns.
How to Overcome Candida Overgrowth
While there may be instances where a short course of antifungal medication is warranted to jumpstart the treatment, over time, candida can become resistant to conventional therapies. To get well, Dr. Rawls emphasizes the importance of treating the underlying illness, which includes restoring healthy immune function and balance in the microbiome.
Step one? Herbal interventions. “Virtually any herb is going to have some effect on yeast,” says Dr. Rawls. “One of the nice properties of herbs is they tend to suppress pathogens without affecting the normal flora. So herbs have a balancing effect on the gut, which is very different than prescription antifungals and antibiotics.”
Certain herbs have been shown to be particularly effective against yeast. They include berberine, andrographis, cat’s claw, garlic, and Japanese knotweed. Additionally, herbs like Reishi mushroom and cordyceps are highly helpful. Both Reishi and cordyceps are fungal species, and some people are hesitant to pit fungus against fungus, but Dr. Rawls assures that both are especially beneficial for balancing the immune system and normalizing immune response.
Also key is reassessing your diet and nixing excess sugar, refined carbohydrates, and starch—yeast’s favorite foods. “If you don’t feed candida, they can’t thrive—simple as that,” says Dr. Rawls.
That means staying away from sweets, fruits, alcohol, processed foods, and grains, and avoiding starchy vegetables such as potatoes, acorn and butternut squash, peas, corn, pumpkin, parsnips, and plantains. Stick with this candida diet until your symptoms subside, then gradually add foods back in — one every few days or so—and watch to be sure your symptoms don’t flare up again.
Beyond that comes adopting all the habits that are vital to supporting a strong immune system, one that’s capable of maintaining healthy balance in your microbiome and keeping yeast and other troublemakers at bay. That includes cultivating eight hours of sleep each night, taking steps to minimize the stress in your life, and reducing your exposure to toxins.
Finally, empower and educate yourself about your condition. While most people with candida overgrowth are able to get a handle on the problem all on their own, sometimes a stubborn infection calls for additional support. So if you do consult with a physician, you’ll be armed and ready with plenty of information to discuss your needs and treatment options with them.
Jenny Lelwica Buttaccio, OTR/L, is a medical, health, and lifestyle writer and editor, and a licensed occupational therapist. Her work has been found in leading publications like HuffPost, Men’s Health Magazine, Prevention Magazine, and many others. Her areas of expertise include chronic health conditions, wellness, mind-body fitness, and chronic illness management. You can find her personal Lyme story on her blog, The Lyme Road or diving into the grassroots, Lyme disease awareness movement, Lyme Disease Challenge. Follow her on Twitter and Instagram.
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