In this article:
- What is candida?
- Candida and your immune system
- Is there a thyroid connection?
- Factors that increase your risk for Candida overgrowth
- Treating Candida
Candida, or yeast, is a microorganism that resides in everyone. Several mechanisms control the amount of candida you have in your system, but sometimes it grows uncontrollably. Historically, we have associated yeast overgrowth in people who are immune-suppressed, such as those with AIDS or leukemia. It is also a well-known side effect in people taking inhaled corticosteroids. But medical science is now discovering that candida overgrowth is not just for those with weakened immune systems but could affect otherwise healthy people.
What is candida?
Candida (yeast) is a fungus that lives inside our bodies. Numerous different strains can cause infections in the human body, but the most common is Candida albicans. Under normal conditions, this type of candida is an essential member of the normal gut flora. However, when certain conditions allow, it can become overgrown, making it transition to an opportunistic pathogen.
Yeast infections can occur in various parts of the body, including the:
- Nasal cavity
In rare cases, candida overgrowth may spread into the bloodstream, reaching the brain, heart, liver, spleen, bones, muscles, joints, and eyes.
Candidiasis, another term for yeast overgrowth, may cause a plethora of symptoms. However, there is little evidence to support many of these symptoms at this time. People who have yeast overgrowth in common areas like the mouth and vagina have burning and itching in the affected areas. Often, you can also see evidence of white overgrowth.
Aside from these common symptoms, candida may also play a role in:
- Brain fog
- Weight gain
- Weakness and muscle pain
- Gas, bloating, diarrhea, and constipation
- Muscle and joint pain
- Food sensitivities
However, there is little evidence to show just how much candidiasis may affect these symptoms.
Candida and your immune system
When candida becomes a pathogen, it releases toxins that may cause an inflammatory response by the immune system. Candida overgrowth in the gut can be particularly damaging, as toxins may leak out of the tight junctions that form between the cells lining your intestines.
One of the prevailing theories behind autoimmune disorders is intestinal permeability, or leaky gut, in which those tight junctions weaken, allowing toxins and larger proteins to escape your digestive tract into your bloodstream. With time, the immune system may start targeting your healthy tissues, causing chronic inflammation and autoimmune disease. Eventually, this may lead to organ failure when your immune system attacks a particular organ.
Pathogens like candida may even cause molecular mimicry, where pathogens change part of their molecular structure so that they go undetected by the immune system. With time, molecular mimicry may also lead to autoimmune disease.
Is there a connection between Candida overgrowth and Hashimoto's disease?
The leading cause of hypothyroidism in the United States is Hashimoto’s thyroiditis, an autoimmune condition. In the case of Hashimoto’s, the immune system sees the thyroid gland as foreign and continuously attacks it. With time, chronic inflammation can make thyroid cells unable to produce thyroid hormone, leading to a state of hypothyroidism.
Candida overgrowth may release toxins through the gut, causing inflammation in targeted organs like the thyroid. Given this potential, there may be a connection between candidiasis and Hashimoto’s. However, there is no definitive evidence that candida may cause Hashimoto’s.
Indeed, researchers aren't entirely sure why some people develop autoimmune disorders like Hashimoto's disease. Causes of autoimmunity are likely from a combination of genes and an outside trigger like a virus or infection. So, while we do not fully know the cause of Hashimoto’s, it is likely that many factors may be at play, and candida may be one of them.
Factors that increase your risk for candida overgrowth
We know that certain circumstances place people at greater risk for candidiasis.
Firstly, we know that certain medications can disrupt the delicate balance of our flora. Known drugs that may lead to candida overgrowth include:
- Proton pump inhibitors (often used to prevent gastric ulcers)
- Antibiotics (which can decrease the number of good bacteria, allowing not-so-good bacteria to flourish)
- Birth control pills and hormone replacements therapy
- Corticosteroids and other medications that attempt to weaken the immune system
Higher than normal estrogen levels can increase a person’s risk for candidiasis. Both men and women have estrogen, and both can be affected by elevated estrogen levels. Not surprisingly, it is far more common in women.
Some research suggests that estrogen binds to candida, causing it to change from its healthy microbial state to a pathogen. The body mounts a stress response when pathogenic candida is present in your system, which can worsen yeast overgrowth.
Your gut is particularly prone to stress, and any stress can throw off your microbiome. In fact, cortisol levels can increase intestinal permeability. When people are chronically stressed, it creates an environment where toxins continuously leak out of the digestive system and enter the bloodstream.
What you eat can significantly impact your gut flora. Some of the more common foods and nutrients in the American diet cause pathogenic candida to thrive. Yeast proliferates when there is plenty of sugar, such as in carbohydrates, fruits, grains, and legumes. Saturated fats may also compromise the balance of your gut flora by fueling other pathogenic species and reducing beneficial bacteria.
Treating candida overgrowth
The treatment options are relatively straightforward for ordinary, overt candida infections like thrush and vaginal infections. Usually, people start by trying an antifungal agent to deplete the pathogenic candida. Certain lifestyle adjustments may also help. For instance, rinsing your mouth regularly if you use a corticosteroid inhaler or wearing breathable underwear if you frequently have vaginal yeast infections.
However, treating candida overgrowth in the gut is far more complex. There is no single test that can determine if you do have candidiasis. A great first step in reducing candida is to treat any underlying health conditions that may be contributing to your body’s inflammatory and stress response. Thus, people with Hashimoto’s hypothyroidism need to treat their thyroid condition to keep up with their metabolic demands.
To reduce pathogenic candida in your body, providers may recommend starting with your diet by following a candida-free or anti-candida diet. Some people also take specific supplements to encourage healthy bacteria to grow.
A note from Paloma Health
No two people are the same, and treating thyroid disease requires assessing the whole person, including lab results, symptoms, lifestyle, and medical history. Partner with a Paloma Health thyroid doctor to determine a personalized thyroid treatment plan and start feeling better—faster!