Hashimoto's Thyroiditis

Causes, Triggers, and Associations of Hashimoto’s Thyroiditis

Imagine trying to solve a puzzle without knowing what the final picture looks like. It’s challenging, right? Similarly, understanding the causes and triggers of Hashimoto’s thyroiditis is like having a clear picture of how that puzzle fits together. It helps you make sense of the condition and empowers you to take proactive steps in managing it. 

Our goal here is to be your compassionate guide through the multifaceted world of Hashimoto’s thyroiditis — because this isn’t just another article, it’s a conversation with you. Together, we’ll explore the underlying causes, potential triggers, and associated factors, all backed by the latest medical research.

By recognizing the factors that might initiate this autoimmune condition or make it worse, you can make informed decisions about your health and well-being. And the best part? Knowledge is power. The more you know, the better equipped you are to navigate the complexities of Hashimoto’s. By the end of this article, you’ll not only be well-informed but also empowered to manage potential triggers.

Whether you’re at the beginning of your autoimmune journey or somewhere in the middle, this article is designed with you in mind. So, while we present the facts, we acknowledge that your health journey is deeply personal, and that’s why our autoimmune care plans at WellTheory are designed to be one-size-fits-you.

Let’s embark on this enlightening journey, understanding that while Hashimoto’s thyroiditis might be a part of your story, it doesn't define you.

Understanding the Immune Response to Hashimoto’s Thyroiditis

Your immune system is like your body’s personal security team. Its primary job is to defend against harmful invaders such as bacteria, viruses, and other pathogens. When it’s working correctly, it identifies these foreign threats and launches attacks to neutralize them, keeping you healthy. (Source)

However, in autoimmune diseases, something goes awry. Instead of just targeting external threats, the immune system mistakenly recognizes the body’s own cells as enemies and starts attacking them. It’s as if your security team suddenly thinks you’re the intruder in your home. In the case of Hashimoto’s thyroiditis, the immune system specifically targets the thyroid gland.

The Thyroid Gland and Its Function

The thyroid gland is a small, butterfly-shaped organ located at the base of your neck. It produces hormones that regulate how your body uses energy, affecting almost every organ. The thyroid plays a pivotal role from how fast your heart beats to how quickly you burn calories.

So, what happens when your body’s defense system targets the thyroid? It disrupts the delicate balance the thyroid maintains. The immune system’s attack on the thyroid often leads to a decrease in the production of thyroid hormones, a condition known as hypothyroidism. This can result in a slew of symptoms, including fatigue, weight gain, and feeling cold all the time. (Source)

Hashimoto’s thyroiditis is more than just a medical term; it’s a complex condition that affects real people like you. Understanding how it works helps you take control of your health and make informed decisions.

Primary Causes of Hashimoto’s Thyroiditis

Genetic Factors

Genetics plays a significant role in many autoimmune diseases, and Hashimoto’s is no exception. Let’s explore this together.

Hashimoto’s thyroiditis doesn’t just appear out of nowhere. It often has roots in your genetic makeup. Think of genetics as a set of instructions that guide how your body functions. Sometimes, these instructions contain variations that can make you more susceptible to certain conditions, including Hashimoto’s.

But here’s the reassuring part: Having a genetic predisposition doesn’t mean you’ll definitely develop the disease. It’s like having a key to a door, but other factors must align to unlock it. Genetics might make you more prone to Hashimoto’s, but environmental factors and lifestyle choices also play a part.

Specific Genes Associated With Hashimoto’s

Now, let’s talk specifics. Research has identified certain genes that might be linked to Hashimoto’s thyroiditis. For example, genes such as HLA-DR and CTLA-4 have been found to be associated with the disease. Sounds technical, right? Just think of them as the “usual suspects” when it comes to this condition. (Source)

  • HLA-DR: This gene is part of the human leukocyte antigen system, which helps the immune system distinguish between self and non-self. Variations in this gene might confuse the immune system, leading it to attack the thyroid gland. (Source)
  • CTLA-4: This gene plays a role in regulating the immune system’s response. Changes in this gene might lead to an overactive immune response, contributing to Hashimoto’s. (Source)

These discoveries are like pieces of a puzzle, helping us understand why some people might develop Hashimoto’s while others don't.

Role of Family History in Risk Assessment

If you’ve got a family member with Hashimoto’s thyroiditis, it's natural to be curious about your own risk.

A family history of the condition can indeed be an indicator of a higher risk. This is because family members share a portion of their genetic makeup, and certain genetic factors associated with Hashimoto’s might be passed down through generations. (Source)

However, it’s essential to approach this knowledge with a balanced perspective. A family history doesn’t guarantee the onset of the condition, but merely means you should be more mindful of potential symptoms and triggers. Genetics is just one piece of the puzzle. Lifestyle choices, environment, and other factors also play significant roles. 

So, while being informed is good, there’s no need to be overly alarmed. Knowledge is power, and understanding your family history with Hashimoto’s can help you make informed choices about your health.

Environmental Factors

Your environment plays a vital role in your overall well-being, and it’s no different when it comes to Hashimoto’s thyroiditis. Let’s explore some of the environmental factors that influence the development of this condition. Understanding these factors doesn’t mean you should live in fear — it’s about empowering you to begin your healing journey.

Iodine Intake and Its Impact on Thyroid Function

Iodine is like a fuel for the thyroid gland, helping produce hormones that regulate many body functions. But like many things in life, balance is key.

  • too much iodine: Excessive iodine intake might trigger or worsen Hashimoto’s in some individuals. It’s like overwatering a plant; sometimes, more isn't better. (Source)
  • too little iodine: On the other hand, insufficient iodine can also lead to thyroid issues. It’s about finding the right balance for your body. (Source)

If you’re concerned about your iodine intake, talk to a health care team who understands your individual needs, or schedule a free consultation with the WellTheory care team.

Radiation Exposure and Increased Risk

Radiation might sound scary, but let’s break it down together. Some studies have shown a link between exposure to radiation and an increased risk of Hashimoto’s thyroiditis. This could be from medical treatments or environmental exposure.

  • medical treatments: Certain medical treatments, such as radiation therapy for cancer, might increase the risk. (Source)
  • environmental exposure: Events such as the Chernobyl disaster have shown that environmental radiation can have long-term effects on thyroid health. (Source)

Recognizing that these are specific situations and probably not part of your everyday life is essential. If you have concerns about potential exposure, the WellTheory team of autoimmune care professionals can guide you to assess your risk and help you monitor and manage your thyroid health.


Infections can sometimes act as triggers for autoimmune diseases, including Hashimoto’s. Here's what the research tells us:

  • viral infections: Certain viruses, such as human herpesvirus 6 (HHV-6), have been associated with Hashimoto’s. (Source)
  • bacterial infections: Recent studies have linked Hashimoto’s thyroiditis to Helicobacter pylori — a type of bacteria that primarily infects the stomach lining and is a common cause of infections within the digestive tract. (Source)

Understanding these links doesn’t mean you should live in fear of infections. It’s about being aware and taking appropriate precautions, like getting regular check-ups and maintaining good hygiene.

Exposure to Some Chemicals

Chemicals such as pesticides, industrial chemicals, and heavy metals have been linked to an increased risk of autoimmune diseases, including Hashimoto’s thyroiditis. (Source)

Now, you might wonder, "How can these chemicals trigger an autoimmune response?" 

It’s a bit like a mistaken identity scenario. These chemicals can alter the structure of proteins in the body. When the immune system encounters these altered proteins it can mistake them for foreign invaders, triggering an immune response — and your body inadvertently starts a war against itself. 

External and Internal Triggers

Understanding the triggers of Hashimoto’s thyroiditis can be a crucial step in managing the condition. Let’s explore some common external and internal triggers that might affect you or your loved ones.


How Does Chronic Stress Affect Hashimoto's Thyroiditis?

Chronic stress is more than just a feeling; it’s a physiological response that can have real effects on your body, including your thyroid. When you’re stressed, your body produces more cortisol, a hormone that can exacerbate autoimmune responses. This means that if you have Hashimoto’s, stress might worsen your symptoms. (Source)

What's the Connection Between Stress and Thyroid Inflammation?

The link between stress and inflammation is well-established. Stress can lead to increased production of pro-inflammatory cytokines, which can trigger an inflammatory response in the body. For someone with Hashimoto’s, this can mean an increase in thyroid inflammation, leading to more pronounced symptoms. (Source)

Practical Tip: Managing stress through mindfulness, exercise, or counseling can be a helpful part of your overall treatment plan. Talk to your health care team about stress reduction techniques that might work for you.

Hormonal Changes

How Do Pregnancy, Menopause, and Hormonal Imbalances Affect Hashimoto’s?

Hormonal changes, such as those experienced during pregnancy or menopause, can affect thyroid function. During pregnancy, for example, hormonal shifts can sometimes lead to postpartum thyroiditis, a condition closely related to Hashimoto’s. Menopause, too, can bring about changes in thyroid function, potentially triggering or worsening Hashimoto’s symptoms. (Source)

What Is Postpartum Thyroiditis, and How Is It Connected to Hashimoto’s?

Postpartum thyroiditis is an inflammation of the thyroid that occurs after childbirth. It’s believed to be an autoimmune condition, much like Hashimoto’s, and the two are often connected. Understanding these connections can help in managing and treating both conditions. (Source)

Practical Tip: If you’re planning a pregnancy or experiencing menopause, discuss your thyroid health with your health care team. Regular monitoring and appropriate care can make a big difference in how you feel.

Medications and Vaccines

Can Certain Drugs and Vaccines Trigger or Worsen Hashimoto’s Symptoms?

Yes, certain medications and vaccines might affect your thyroid function. Some drugs, such as interferon and lithium, and vaccines such as those for COVID-19, have been associated with triggering or worsening Hashimoto’s symptoms. (Source, Source)

Why Is It Important to Discuss Potential Risks with Health Care Providers?

Your health care team knows your medical history and can help you understand the potential risks and benefits to you of medications and vaccines. Open communication ensures you receive the care best suited to your needs.

Practical Tip: Always inform your health care team about any medications or supplements you take. This collaboration can help in managing your Hashimoto’s symptoms effectively.

Secondary Causes and Associations

So, you understand the primary causes of Hashimoto’s thyroiditis. But what about the secondary causes and associations? These are the factors that, while not directly causing the disease, can significantly influence its onset and progression. They can be seen as pieces of a puzzle that, combined with the primary causes, complete the picture of this complex condition. Let’s delve deeper to uncover these pieces.

Other Autoimmune Diseases

What Other Autoimmune Diseases Often Coexist With Hashimoto’s Thyroiditis?

Hashimoto’s often doesn’t walk alone. It may coexist with other autoimmune conditions such as celiac disease, type 1 diabetes, and rheumatoid arthritis. This connection isn’t a coincidence, but part of what is sometimes referred to by some as an autoimmune spectrum. (Source)

What Is the Autoimmune Spectrum, and Why Does It Matter?

The autoimmune spectrum is a concept that recognizes the interconnectedness of autoimmune diseases. One autoimmune condition may increase the likelihood of developing others. Understanding this spectrum can guide both diagnosis and treatment, offering a more holistic approach to care. (Source)

Practical Tip: If you have Hashimoto’s, be aware of other autoimmune conditions and discuss them with your health care team. Early detection can make management more effective.

Dietary and Lifestyle Factors

Can Gluten Worsen Hashimoto’s Symptoms?

Yes, gluten might play a role, especially if you have celiac disease alongside Hashimoto’s. Some research suggests that a gluten free diet may help reduce Hashimoto's antibodies. (Source)

What About Smoking?

Smoking has been associated with an increased risk of developing Hashimoto’s and can worsen the symptoms. Quitting smoking can be a positive step toward better thyroid health. (Source)

Practical Tip: Discuss dietary and lifestyle changes with your health care team. Personalized guidance and care plans can make these transitions smoother and more effective.

Gut Health

What Is the Gut–Thyroid Axis, and Why Is It Significant to Hashimoto’s?

The gut–thyroid axis is the relationship between your gut health and thyroid function. Your gut is home to trillions of microorganisms that are vital to immune regulation. With 70%–80% of your body’s immune cells being present in the gut, an imbalance in this microbiota may lead to immune dysfunction that affects thyroid health, including Hashimoto’s. (Source)

Practical Tip: Probiotics and a balanced diet can support gut health. Talk to your health care team about options that might be right for you.

Vitamin D and Selenium Deficiencies

How Does Vitamin D Affect Immune Function and Hashimoto’s?

Vitamin D is more than just a nutrient for strong bones — it’s vital to your immune system’s well-being. You might be wondering how exactly it plays such a role. Vitamin D, which cells in your skin can synthesize after exposure to sunlight, acts as a kind of double agent in your body. 

On one hand, it encourages the production of antimicrobial proteins, your body’s natural defense against infections. On the other hand, it helps control inflammation, which, if left unchecked, can cause serious harm to your body’s systems.

A deficiency in vitamin D has been specifically linked to Hashimoto’s thyroiditis. Vitamin D plays a key role in modulating immune responses, which can directly affect Hashimoto’s. In fact, there’s evidence to suggest that vitamin D may help reduce thyroid antibodies in those with this condition, thereby playing a part in managing the disease. This fascinating connection underscores the importance of maintaining proper vitamin D levels as part of your overall health strategy. (Source)

What Is the Role of Selenium in Thyroid Health?

Your body relies on selenium to assist in converting the thyroid hormone T4 into its active form, T3. If you can picture a production line in a factory, selenium is like the skilled worker who ensures everything runs smoothly. 

Selenium also serves a crucial role in protecting your thyroid gland from oxidative damage. Think of it as a bodyguard for your thyroid, safeguarding it from harmful free radicals that can disrupt its function. Without it, your thyroid would be left vulnerable, much like a fortress without its guard.

But how does a deficiency in selenium impact your thyroid health? Low levels of selenium have been linked to autoimmune thyroid disorders, including Hashimoto’s thyroiditis. This association suggests that maintaining adequate selenium levels could be key in managing this condition. (Source)

Practical Tip: Regular monitoring of vitamin D and selenium levels and appropriate diet supplementation can be part of your Hashimoto’s care plan.

Other Associated Conditions

What Other Conditions Are Associated with Hashimoto’s?

Research has shown Hashimoto’s is often associated with other autoimmune conditions. (Source)

Examples of these include:

  1. anemia
  2. vitiligo
  3. rheumatoid arthritis
  4. type 1 diabetes
  5. adrenal insufficiency
  6. Graves’ disease
  7. celiac disease

Practical Tip: Open communication and regular check-ups with your health care team can help manage not just Hashimoto’s but your overall well-being.

As you can see, Hashimoto’s isn't caused by a single factor. Understanding this interconnectedness helps you see the bigger picture, recognizing that managing Hashimoto’s isn’t about addressing one aspect, but embracing a comprehensive approach.

The Bottom Line

Managing Hashimoto’s is a journey, and you don't have to walk it alone. By understanding the underlying causes and potential triggers, you’re empowered to take control of your thyroid health. Recognizing what might worsen your symptoms allows you to make informed decisions, whether it’s managing stress, making dietary changes, or working closely with your health care team.

Yes, managing Hashimoto’s is a team effort! Your primary health care provider offers medical expertise, your therapists provide emotional support, nutritionists guide dietary choices, support groups offer community, and WellTheory brings a modern, integrative autoimmune care approach to understanding the root causes and guiding you on the journey to faster healing.

With a focus on evidence-based nutrition and lifestyle coaching, WellTheory’s personalized approach to autoimmune care can help you (or your loved ones) better manage Hashimoto’s thyroiditis. Our care team at WellTheory, consisting of people with lived experiences with autoimmune conditions, offers long-term support tailored to your evolving needs, promoting better health through daily lifestyle choices in nutrition, sleep hygiene, stress management, movement, and fostering positive relationships.


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