Depending on who you ask, Candida overgrowth is either entirely made up or the root of all disease. 

Some experts claim as much as 90% of people have chronic candida overgrowth and it causes a gamut of health issues from weight gain to cancer. Others say it’s only an issue in acute cases like oral thrush or vaginal yeast infections (which can be easily treated and eradicated). 

So what’s the truth?

As with most things, the truth is somewhere in the middle. Chronic candida is a research-backed condition, but that doesn’t mean everything you’ve heard about it is true. 

As a functional medicine practitioner, I’m interested equally in what the research has shown and what my patients are experiencing. In this series, I’m going to share everything I know—both from research and anecdotal experience—about candida overgrowth with you. 

This will be a multi-part blog post. Today, we’re going to focus on what Candida is (and isn’t) and how it presents.


Part 1: What The Heck Is Candida?

First of all, you need to know that 99% percent of the time, when you hear “Candida,” it refers to Candida albicans. 

Other species do exist (C. glabrata, C. krusei, C. tropicalis and C. parapsilosis for example) but C. albicans is the most common. For the rest of this post, know that I’m talking about C. albicans when I say “Candida.”

OK—moving on.

Candida is normally a commensal fungus that lives in your oral, gastrointestinal, and genital tracts and is part of the “world of microorganisms” that live inside your body and make up the microbiome. 

“Commensal” means that Candida gets nutrients from you without causing any harm. Your body recognizes the Candida as a “friendly” fungus and doesn’t mount an immune response against it. 

As a commensal fungus, Candida is very common: approximately 80% of healthy people have commensal Candida living in their mouths, guts, and vaginas. In fact, it’s completely normal for Candida colonization of the vagina to increase in puberty as hormonal shifts make the vagina even more hospitable to fungal growth.

The main point is: Candida isn’t all bad! For most people, it’s just part of a healthy microbiome.

But that can change when Candida shifts from “commensal” to “pathogenic.” 


Here’s What Happens When Candida Breaks Bad

Under specific conditions, Candida can shift from it’s normal commensal state to a pathogenic state, overgrow, and cause symptoms. 

This happens in two ways:

#1 Candida Changes Form

Under certain circumstances (like a change in temperature or acidity) Candida can go through a process called “morphogenesis” and change form from one your body recognizes as friendly to one it sees as an enemy. The result is an immune response from your body toward the new form of candida. This is also when candida can grow “roots” – aka hyphae – and start burrowing into intracellular space. 

#2 Your Body Starts Reacting To Candida

The Candida doesn’t always have to change form for a response to happen. In vulvovaginal candidiasis (vaginal yeast infection), the Candida that’s normally present in the vagina doesn’t necessarily change form (although that can also happen) – but the tissue of the vagina creates an immune response against the Candida. 

This means that the symptoms are caused both by Candida changing form AND your body changing how it reacts to the Candida. 


Acute vs. Chronic Candida Overgrowth

Acute Candida overgrowth is called candidiasis. This is the typical vaginal yeast infection or oral thrush, but can also cause infections in the esophagus and intestines. 

The acute form results in an overgrowth of yeast on mucosal surfaces (like your mouth and vagina), but that’s not all. During active infection, Candida can grow hyphae, which are like roots that can burrow into intracellular spaces. With hyphae, Candida can invade deeper tissues and grow inside the epithelial cells. There, they release products of fermentation and enzymes that kill the tissue cells. The result are the white patches that characterize candidiasis (the white is actually dead cells, not clumps of Candida colonies!).

Acute candidiasis is often treated with a short course of antifungal drugs or herbals. But if the treatment is incomplete, the yeast in the epithelial cells won’t be totally eradicated… leading to chronic Candida overgrowth symptoms. 

In the chronic form, the Candida is inside the epithelial cells, instead of just on the surface of the cells. The yeast is “dormant” but still releasing antigens that trigger inflammation, and can result in red and inflamed tissues. 

The low-grade inflammation caused by chronic Candida can cause pain, tenderness, burning, and more. This is especially common with vaginal yeast infections.


A Closer Look At Vaginal Yeast Infections

About 75% of women will be diagnosed with a vaginal yeast infection at least once in their lives, and Candida is the cause of about 40% of all vaginitis cases. A vaginal yeast infection is probably the most common type of acute Candida overgrowth or candidiasis. 

They’re most common in women of reproductive age because they have higher estrogen levels – and estrogen promotes yeast in the vaginal tissues. (Side note: this is also why oral contraceptives increase your risk of yeast infections—they contain synthetic estrogen. More on this to come!)

The symptoms are all too familiar to most women: Itching, redness, burning, white discharge, painful intercourse, yeasty odor, and painful intercourse from tissue irritation. It can also lead to vaginitis and urinary tract infections (UTIs). 

The worst part, however, is that yeast infections can become a vicious cycle for women, as the antibiotics used to treat UTIs and vaginitis make women MORE susceptible to yeast infections recurring. 

We know that repeat infections can lead to vulvodynia (vaginal pain and tissue irritation) that makes sex painful and everyday activities (like wearing yoga pants and using tampons) uncomfortable. The vulvodynia may very well be caused by the low-grade inflammation of chronic Candida leading to irritated vaginal tissue cells. 

But complications from vaginal yeast infections are just one way candida overgrowth can impact your life. 

In Part 2 of this series, I’m going to dig into the symptoms chronic candida can cause—and I’m going wayyy beyond just “sugar cravings!” You’ll also learn what the risk factors and predisposing conditions for Candida are. 


Recap: Candida Overgrowth

Because this is  an intense topic, I want to give a really quick recap before we wrap up this first part of the series.

Here are the main points:

  • “Candida” usually refers to Candida albicans
  • Candida is a normal, healthy yeast (type of fungus) that lives in about 80% of peoples’ microbiomes
  • In certain circumstances, candida can overgrow and change form, causing two types of Candida overgrowth problems:
    • #1 Acute Candida Infections – like vaginal yeast infections and oral thrush 
    • #2 Chronic Candida Overgrowth – low-level, long-lasting candida overgrowth, often a result of incomplete treatment of an acute infection

OK—that’s all for now! I’ll see you back here for Part 2, where we’ll go over the symptoms and root causes of Candida overgrowth in-depth!