Whenever I have talked with thyroid patients with a family history of hypothyroidism, it was always the same question: is hypothyroidism genetic? The answer to that question is that it depends. 

Genetics plays a small part in your risk of hypothyroidism. However, it doesn’t mean that if you have a family history of hypothyroidism it puts you at a higher risk to develop it. There are several causes of hypothyroidism that I will talk about later, along with the role genetics plays in hypothyroidism, and what the risk factors are. 

Conventional medicine would lead you to believe that once you have hypothyroidism, you will have it for the rest of your life. As a functional medicine doctor, and as a former thyroid patient, I know that is simply not true. 

In functional medicine, we look at the body as a whole instead of specialties. We get to the root cause of your problem, which begins in your gut and your immune system. Through diet and lifestyle changes, you CAN take back your health and reverse your hypothyroidism. I will tell you how you can do that with my proven solution to address the root cause of your symptoms so you can achieve optimal health. Before I do that, let’s talk about what causes an underactive thyroid, or hypothyroidism.

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What are the Major Causes of Hypothyroidism?

Hypothyroidism is the most common thyroid disease. When your thyroid is underactive, it’s not producing enough thyroid hormone. This can happen for various reasons. Here are the major causes of hypothyroidism from the most common to the least common.  

Is Hypothyroidism Genetic – Causes of Hypothyroidism – Infographic – Amy Myers MD®Is Hypothyroidism Genetic - Causes of Hypothyroidism - Infographic - Amy Myers MD® https://content.amymyersmd.com/article/is-hypothyroidism-genetic/Is Hypothyroidism Genetic – Causes of Hypothyroidism – Infographic – Amy Myers MD®

Autoimmune Disease

The most common cause of hypothyroidism is Hashimoto’s thyroiditis, an autoimmune disease where your immune system attacks your thyroid. As with any autoimmune disease, inflammation is one of the primary symptoms of Hashimoto’s and it often leads to an underactive thyroid gland. When your immune system cannot tell the difference between healthy cells and foreign invaders, it just attacks everything in sight. This includes the cells and enzymes in your thyroid that make the thyroid hormone. Hashimoto’s is more common in women than in men. 

Removal of Part or All of the Thyroid

Some people with thyroid nodules, cancer, or Graves’ disease have part or all of their thyroid removed. If you don’t have a thyroid you will get hypothyroidism. If only part of the thyroid gland is left after surgery, then it can make normal amounts of the thyroid hormone. However, it cannot make optimal amounts and you could have the symptoms of hypothyroidism, which I will discuss later. 

Radiation Treatment 

When I was diagnosed with Graves disease in medical school, conventional medicine gave me three options – medication, have it surgically removed, or use radioactive iodine to ablate my thyroid (blow it up). I eventually decided to have my thyroid ablated, a decision I regret to this day. Radiation treatment is also used on brain or neck cancer patients, those with Hodgkin’s disease, and lymphoma. Radiation treatment will cause you to lose all of your thyroid function. 

You’re Born With It

I’m not talking about genetics, when I say “you’re born with it.” There are times when a baby has part or all of their thyroid in the wrong place. This is known as an ectopic thyroid. 

In other cases, a newborn may just not have a thyroid that doesn’t work right. The most common cause of thyroid birth defects is a lack of iodine in the mother’s diet. Iodine is necessary for the production of the thyroid. 

It is important to point out that 15 to 25% of the cases of congenital hypothyroidism are caused by genetics. 


Heart medications such as amiodarone and lithium and immune system medications such as interferon-alpha and interleukin-2 can inhibit the production of the thyroid hormone. This is one area where genetics plays a role in the risk of developing hypothyroidism. These medications increase the risk of hypothyroidism in people with family members with Hashimoto’s or Graves disease.

Too Little Or Too Much Iodine

As I’ve mentioned, iodine is necessary for the thyroid to function and make the thyroid hormone. You get it from food. Seaweed, fish and shellfish, table salt, eggs, beef liver, and free-range chickens are good sources of iodine. Keeping thyroid hormone production in balance requires the right amount of iodine. The recommended daily value (RDV) is 150 mcg per day. 

Damage to the Pituitary Gland

Your pituitary gland is responsible for sending thyroid-stimulating hormone (TSH) to your thyroid gland to signal it needs to make T4 and T3 hormones. Even if your TSH levels are normal, if you have hypothyroidism, your thyroid gland won’t produce enough T4 and T3 to fuel cells. Most conventional medicine doctors only test your TSH levels and free T4 levels for normal ranges. However, there’s a difference between normal levels and optimal levels. The pituitary gland can become damaged due to radiation, surgery, or head trauma. 

As you can likely see, genetics wasn’t a part of the main causes of hypothyroidism. However, that doesn’t mean it’s not a factor. 

Does Hypothyroidism Run in Families?

To answer the question of is hypothyroidism genetic, you have to understand the unique genetic code that makes you, you. Everyone has a different genetic makeup that includes certain defects, variations, or mutations. We all have them! The most common gene mutation is the MTHFR gene. 

Methylenetetrahydrofolate reductase (MTHFR) is an enzyme that breaks down the amino acid homocysteine, which breaks down dietary protein. High levels of homocysteine can lead to blood clots or damaged blood vessels, People that have high levels of homocysteine are more likely to be vitamin B12 deficient.

Functional medicine has done extensive research on MTHFR mutation and MTHFR support which has become increasingly accepted in modern medicine. 

Not only does MTHFR mutation decrease your body’s ability to detoxify, it’s also linked to over 60 chronic health conditions, including Hashimoto’s and hypothyroidism. Having a family history of MTHFR gene mutation increases your risk of also having it. This would indicate that hypothyroidism is genetic. 

Your doctor can order genetic testing to test for MTHFR mutation, or they may perform a blood test to check homocysteine levels. If you have or suspect MTHFR mutations, you should consider Methylation Support®

Methylation is a biochemical process that, among many other critical functions, transforms toxins into safer substances that will not harm your body. This process depends on several vitamins and cofactors, including folate, vitamin B12, and vitamin B6. 

Methylation Support® is the perfect blend of the nutrients your body needs to engage in optimal methylation. I custom-selected these nutrients in their most bioavailable forms to support the body’s methylation and detoxification efforts. 

What Age Is Most Likely to Get Hypothyroidism?

People between the ages of 30 and 50 are more likely to develop hypothyroidism, however, it can affect anyone over the age of 12. Hypothyroidism caused by Hashimoto’s is more common among women and is more likely to develop in those who have increased risk factors such as gluten sensitivity, B12 deficiency, lupus, type 1 diabetes, and Rheumatoid arthritis, and Addison’s disease, a condition that affects your adrenal gland. 

The Early Warning Signs of Hypothyroidism include: 

Testing for Hypothyroidism

It should come as no surprise given conventional medicine’s “one-size-fits-all” approach to thyroid disease focuses on treating symptoms rather than getting to the root cause of your condition. Unfortunately, conventional doctors are still using this outdated model.

Here are three methods to determine if you have a thyroid problem: 

  • Ultrasound: This is helpful to look at nodules on the thyroid, and your doctor may request you have a fine needle biopsy to confirm that the nodules are not cancerous.
  • Radioactive iodine uptake (RAIU): This is the next step in diagnosing a thyroid imbalance. An RAIU using a small dose of I-131 will determine how much iodine the thyroid takes up. A high iodine uptake is indicative of Graves’ disease. This test can help rule out other possible causes of an overactive thyroid.
  • Blood testing: This is the first step. In hyperthyroidism, the thyroid-stimulating hormone (TSH) will be very low and the Free T4 and Free T3 will be elevated. In autoimmune conditions, you will see elevated levels of antibodies as well. I recommend the home thyroid test from LetsGetChecked to test your thyroid hormone levels. If you want a more comprehensive look at your thyroid health, LetsGetChecked offers a thyroid antibody test. The results are available online and you can take them to your functional medicine doctor to go over them. 

What are the Optimal Lab Values for Thyroid Tests?

I found that these are the ranges below are the ones in which my patients thrive: 

  • TSH 1-2 UIU/ML or lower (Armour or compounded T3 can artificially suppress TSH)
  • FT4 >1.1 NG/DL
  • FT3 > 3.2 PG/ML
  • RT3 less than a 10:1 ratio RT3:FT3
  • TPO – TgAb – < 4 IU/ML or negative

Thyroid medication can help you manage your thyroid levels, however, that is only part of the process. The real work comes in identifying the early warning signs of a thyroid problem and addressing the underlying factors and supporting your thyroid health. Let me tell you how to do that. 

The Best Supplements for Hypothyroidism

In my New York Times bestseller, “The Thyroid Connection” I talk about my proven method that I’ve used with thousands of patients and seen amazing results in my decades of experience as a physician. I call it The Myers Way®. The Myers Way® rests on four pillars to get to the root cause of your hypothyroidism and reverse your condition. 

Even if you’ve followed The Myers Way® for any amount of time, it is still important to support your thyroid health. I designed my Hashimoto’s Support Plus Kit specifically for those with low thyroid, hypothyroidism, and Hashimoto’s Disease. 

Having suffered from a thyroid condition myself, I’m aware of how big of an issue  thyroid disease is. If you have been newly diagnosed with low thyroid, hypothyroidism, or even an autoimmune disease that attacks and suppresses your thyroid such as Hashimoto’s Disease, then I designed this kit for you. 

The Hashimoto’s Support Plus Kit includes The Myers Way® Multivitamin to include optimal amounts of selenium, zinc, and iodine to support optimal thyroid health. I formulated this potent multivitamin with thyroid health in mind. 

The kit also includes Adrenal Support to promote a more balanced physical and emotional stress response, while encouraging healthy energy levels. This physician-formulated supplement contains key nutrients in their most bioavailable forms to support the adrenal glands. 

Finally, ZenAdapt is also included in Hashimoto’s Support Plus Kit. This powerful blend of adaptogenic herbs supports optimal cortisol levels and promotes a balanced stress response. 

Genetics plays only a small role in hypothyroidism. While you cannot do anything about genetics, you can support your thyroid health with optimal amounts of nutrients, recognize the early warning signs, and get to the root cause. As a former thyroid patient, I know that you can reverse your hypothyroidism with the tools I’ve given you. 

Adrenal Support bottle