Hashimoto’s Disease Causes
Molecular Mimicry and Cross-Reactivity
It's important to understand that Hashimoto's disease causes are not well understood, but we have a much better foundation of research on autoimmune triggers and drivers than ever before.
The leading theory behind the activation and continued perpetuation of autoimmunity is a concept called molecular mimicry.
Molecular mimicry is simple.
Molecular mimicry is the idea that your immune system reacts to something foreign, like a food, pathogen or chemical that looks so much like one of the many proteins that make up your body, that the immune system mistakenly attacks your tissues.
The process of reacting to your tissues due to molecular mimicry is called cross-reactivity.
Once the tissues of your body have been tagged by circulating antibodies, you have lost self-tolerance and are now susceptible to the destruction of the tagged tissues by other immune system cells.
So what are the symptoms of Hashimoto's thyroiditis?
Symptoms of an Autoimmune Thyroid
Symptoms associated with Hashimoto’s disease:
- Fatigue
- Weight Gain / Obesity
- Constipation
- Hair Loss
- Dry, pale skin
- Weak, brittle nails
- Depression
- Cold hands, feet, and the tip of the nose
- Prolonged, heavy menstrual bleeding
- Problems with memory and concentration “Brain Fog”
Common symptoms of Graves’ disease include:
- Anxiety
- Depression
- Trouble Sleeping, Insomnia
- Increased heart rate
- Weight loss
- Bulging eyes
- Sensitivity to warm or hot environments
- Enlarged thyroid (goiter)
What risk factors are believed to cause Hashimoto's disease?
Risk Factors for Hashimoto’s Disease
Several risk factors for developing Hashimoto’s disease have been identified:
- Sex - Females are more likely to develop Hashimoto’s
- Age - Age of onset is usually middle age, but more common around puberty, pregnancy, and perimenopause in women.
- Genetics - If other people in your family have an autoimmune disease you are at a greater risk of developing Hashimoto’s.
- Having another autoimmune disease - You have an increased risk of developing Hashimoto’s, especially if you have been diagnosed with rheumatoid arthritis, lupus, or type 1 diabetes.
- Exposure to radiation - exposure to elevated amounts of radiation increases the risk of developing Hashimoto’s disease.
- Exposure to environmental toxins or heavy metals
- Intestinal hyper-permeability “Leaky Gut”
Hashimoto’s Disease Causes, 3 Key Factors
The continued study of the immune system and drivers of autoimmunity has advanced our understanding of the autoimmune process, and in particular, three key factors have been identified as requirements to develop autoimmunity.
- Genetic Predisposition
- A Trigger
- Intestinal Permeability
Genetic Predisposition
The leading theory behind how we trigger Hashimoto's is that there must be a genetic predisposition.
How do you know if you have a genetic predisposition to develop Hashimoto's?
We don't know the exact genes that are required to cause Hashimoto's disease, but we do know that if you have an immediate family member with autoimmunity you, too, are more likely to develop an autoimmune condition.
In addition to having a genetic predisposition to cause Hashimoto's disease, you also need a trigger.
Immunological Trigger
Research suggests that there are several triggers for Hashimoto's and other autoimmune conditions that fall within three categories:
- Food Sensitivities (peptides)
- Pathogens
- Chemicals
Hashimoto's Disease Causes - Trigger #1 Food Sensitivities
Hashimoto's Disease Causes - Trigger #2 Pathogens
Hashimoto's Disease Causes - Trigger #3 Chemicals
Intestinal Permeability
Intestinal permeability is a condition where the intestinal lining develops larger than normal gaps, or holes that allow materials, that in a healthy gut, should not pass from inside the intestinal tract into the bloodstream.
Intestinal permeability is also commonly referred to as "leaky gut."
You can learn more about intestinal permeability or leaky gut in my video below.
Other Hashimoto’s Disease Triggers
There is no agreed-upon cause of Hashimoto’s disease except that it is multifactorial. Scientists believe a variety of factors could contribute to the development of Hashimoto's:
- Stress (Chemical, Physical, Emotional)
- Intestinal Permeability “Leaky Gut”
- Immunological reactivity to environmental chemicals
- Immunological reactivity to pathogens (bacteria, viruses, fungi, parasites)
- Immunological reactivity to dietary triggers (peptides) a.k.a. “food sensitivities”
- Nutrient deficiency
- Insufficient sleep
- Genetic predisposition
Of the suspected Hashimoto's disease causes, there are five factors that sit at the top of the list.
Top 5 Hashimoto’s Disease Causes
Do you know the top 5 Hashimoto's disease causes?
Research suggests several mechanisms behind the initiation and perpetuation of autoimmune conditions like Hashimoto's.
The Top Five Causes of Hashimoto’s Disease Are:
- Selenium Deficiency
- Wheat Gluten
- Iodine
- Molecular Mimicry
- Poor Repair of The Intestinal Lining
#1 Selenium Deficiency
- Decreased selenium-dependent proteins
- Insufficient Glutathione Peroxidase (GSH)
- Results in increased inflammation from Hydrogen Peroxide not being neutralized by GSH
(Animal studies show protective benefit from selenium consumption)
Supporting Selenium
- Typical recommendations for selenium are 200-400 mcg per day from ALL sources, including food
- Selenium can be toxic
- Serum level targets may need to be 140 mcg/L or higher
#2 Wheat Gluten
- Wheat gluten shown to cause intestinal permeability “Leaky Gut”
- Leaky gut allows bacterial antigens and food peptides into circulation
- Through “Molecular Mimicry” immune system attacks thyroid mistakenly
Addressing Wheat Gluten
- Get Tested:
- Gluten Sensitivity
- Celiac Disease
- DQ8 genetic testing for susceptibility
- Eliminate from diet for at least 2 - 3 months
- Lab testing can be false negative
- Fecal Testing
- Anti-gliadin antibodies
- Cross-Reactive Foods
- If gluten sensitive, gluten cross-reactive foods must be assessed
- Consider Digestive Enzymes for Oral Tolerance
#3 Iodine
There is conflicting research on Iodine’s role in Hashimoto’s.
It is believed to be multifactorial, and not an issue of iodine alone being the problem.
It appears too much, and too little are both problems and potential triggers.
Iodine - Too Much As A Trigger
Some studies show iodization of the food supply has increased the incidence rate of Hashimoto’s.
Animal studies with mice show iodine can trigger Hashimoto’s.
Could Iodine Cause a Hashimoto’s Flare Up?
The scientific literature suggests iodine can cause hyperthyroidism in some cases.
- Some medications high in iodine
- Radiographic contrast with iodine
- Unidentified thyroid nodules “Hot Nodule” with mutated TSH receptors
Iodine - Deficiency As A Possible Trigger
Hashimoto’s has increased while iodine levels have dropped over the past several decades.
Why not a decrease in Hashimoto’s if Iodine is a trigger?
Iodine, what to do?
- Iodine is essential for thyroid hormone production, but its use must be monitored for possible adverse response
- Establish sufficient selenium levels first ~ 140 mcg/L
- Consider iodine at 225 - 450 mcg per day
#4 Molecular Mimicry
Theory where the immune system mistakenly attacks the thyroid (Cross-reactivity) because it is reacting to something foreign that has a similar protein structure (Molecular Mimicry) to TPO, TGB, TSH receptors, sodium iodide symporter, or other tissues, hormones, enzymes essential to thyroid function.
Molecular Mimicry
You must test to determine immunological reactivity to pathogens, food peptides, and chemicals or chemical metabolites that are driving an immune response.
There is no way to know what an individual is reacting to without quantification via laboratory testing.
#5 Poor Intestinal Repair - Leaky Gut
Poor ability to repair the intestinal lining results in intestinal permeability, or “Leaky Gut”.
Leaky Gut has been identified as a likely contributing factor in a number of health problems:
- Autoimmunity
- Obesity
- Chronic Fatigue Syndrome
- Ulcers
- IBS
- Inflammatory bowel disease
- Thyroid disorders
- Parkinson's Disease
Deficiency in key nutrients will impair the regeneration of the intestinal barrier.
1) Glutamine
2) Zinc
Glutamine and zinc could be low due to poor absorption, stress, dietary approaches (vegan, vegetarian).
What to Do About Poor Intestinal Repair - Leaky Gut
The ideal approach to Leaky Gut is to test, then support what you find.
It’s impossible to know if someone has intestinal permeability or what is causing it without testing.
The trial and error approach:
- Supplement with vitamins, minerals, herbs (glutamine and zinc may help)
- Remove potentially irritating foods
- Decrease stress
- Get sufficient sleep (8 to 10 hours)
Hashimoto’s Flare Up
It's important to mention that Hashimoto's disease is often associated with symptoms of both hypothyroid and hyperthyroid activity.
Hashimoto's is classically associated with low or hypothyroid symptoms, but it's not uncommon for people with Hashimoto's to experience a Hashimoto's flare up.
A Hashimoto's flare up can cause a temporary spike in thyroid hormone that results in symptoms of hyperthyroidism.
As I mentioned before, we don't know for sure what causes Hashimoto's because it's an autoimmune condition.
Hashimoto's flare-ups are the results of the autoimmune process "flaring" or becoming more active.
The increase in symptoms associated with a "Hashimoto's flare" is believed to be the result of increased inflammatory load and cytokines, and a temporary surge in thyroid hormone levels when the thyroid tissue is destroyed causing spilling of thyroid hormones into the bloodstream.
Tips for Avoiding Hashimoto’s Flare Ups
Hashimoto’s With Normal TSH
You may be surprised to find out that you can have Hashimoto's with normal TSH.
Technically, Hashimoto's is a clinical diagnosis and thyroid antibodies and hypothyroidism (high TSH) are factors considered when your doctor makes the official diagnosis.
It's important to understand that you can have thyroid antibodies and a normal TSH.
Typically having Hashimoto's with normal TSH is a good thing.
Having a Hashimoto's with a normal TSH suggests that you are in an earlier stage of the autoimmune process.
Having a normal TSH with Hashimoto's typically indicates the thyroid is still able to manufacture adequate thyroid hormone (T4 and T3) becasue the TSH is still normal, and not yet elevated due to a deficiency.
When thyroid hormone goes down, TSH should go up.
There are three main phases of thyroid autoimmunity that you need to know about. I'll explain more in the following video.
3 Stages and Progression of Autoimmunity
Now that you have a better understanding of the phases of autoimmunity let's discuss some of the potential complications of Hashimoto's disease and Hashimoto's flare-ups.
Complications of Hashimoto’s
It’s important to understand that autoimmune conditions are considered progressive diseases. There is the potential for complications with Hashimoto’s disease, especially if left untreated.
Some of the possible complications with Hashimoto’s are:
Hashimoto’s disease could also progress to other diseases and is associated with hypothyroidism, thyroid lymphoma, and papillary thyroid carcinoma.
Hashimoto’s progresses to hypothyroidism due to progressive destruction of the thyroid gland.
This progressive destruction of the thyroid reduces the glands capacity to produce thyroid hormone.
Hashimoto’s is also associated with thyroid lymphoma and papilla.
Hashimoto’s and Autoimmune Expansion
Hashimoto’s disease is associated with other autoimmune diseases.
If you have Hashimoto's it means you could have or could develop other autoimmune conditions.
Research indicates the most common autoimmune conditions found with Hashimoto’s are dependant on sex and age.
I use a science-based approach to help people across the US and Internationally to investigate the drivers of their autoimmunity and implement a plan to support their health.
If you would like to learn more about the approach I use, click here Hashimoto's Doctor Method.
National & International Distance consultations available via phone and video, visit New.ThyroidConsult.Com to learn more
Self-help programs - learn more at ThyroidProgram.com
Online Support Group - Facebook - Greater Hickory Thyroid Support Group
About the Author:
Dr. Shook has psoriasis and Hashimoto's disease and has trained extensively in functional medicine, epigenetics, and human performance optimization. DrBradShook.com is a resource to help people with Hashimoto's disease, thyroid dysfunction, and other autoimmune conditions learn more about how they can complement their current medical care and support their thyroid and autoimmunity naturally.
