The Benefits of Thiamin for Thyroid Disease

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Typically, most symptoms of thyroid disease can be resolved through appropriate treatment. However, some patients still suffer from lingering and in some cases, debilitating fatigue even after these steps have been taken.

There are multiple reasons why fatigue may linger, but an important factor that may be overlooked is thiamin deficiency. Thiamin influences multiple important systems including the thyroid gland. Knowing the essential role of thiamin, identifying deficiency, and taking the appropriate steps to balance thiamin levels can help alleviate thyroid issues and fatigue.

What is Thiamin?

Thiamin, also known as Vitamin B1, is part of the B-complex of vitamins. This group is noted for their positive impact on immune function and the body’s stress response. Like other essential vitamins, thiamin is not produced by or stored in the body. Therefore, thiamin must be acquired from external sources. Thiamin can be found in many common foods of both plant and animal varieties.

Some of the best sources of thiamin include:

  • Beef liver
  • Blackstrap molasses
  • Dried milk
  • Eggs
  • Enriched, fortified, or whole grain foods including bread, pasta, rice, cereals, and flours
  • Legumes such as beans and peas
  • Nuts and seeds
  • Pork
  • Poultry

Thiamin has multiple benefits including metabolic regulation, stomach acid release, and improved fat and protein digestion. The main function of thiamin is to convert carbohydrates into usable energy. The brain and nervous system rely heavily on the energy produced through thiamin activity. If the body is not able to effectively utilize thiamin, many symptoms can develop. The most prominent and common being fatigue.

What Does Deficiency Look Like?

Thiamin deficiency is frequently seen in chronic conditions that cause long-lasting fatigue. Some experts believe that Americans do not have adequate intake of thiamin in their diet, meaning that they fall short of the recommended daily allowance of 1.0 to 1.1 mg per day. Those on paleo or autoimmune diets may also be at risk of thiamin deficiency because many sources of thiamin are not allowed in these diet plans.

In addition to diet, there are many other factors that may contribute to thiamin deficiency including malabsorption, alcoholism, diabetes, and poor metabolic function. Other conditions such as Crohn’s disease, anorexia, and kidney disease can also promote thiamin deficiency. Using certain medications such as diuretics, seizure medications, and some heart medications like Digoxin may further reduce thiamin levels. When these contributing factors are present along with thyroid dysfunction and autoimmune issues, fatigue can become severe and in some cases debilitating.

The Thyroid and Thiamin

One of the most common symptoms of an underactive thyroid, or hypothyroidism, is fatigue. Typically, appropriate medical treatment, hormone therapy, and dietary optimization can resolve the many nagging symptoms of hypothyroidism including fatigue. However, some patients continue to suffer from long-lasting fatigue even after treatment.

Research suggests that many hypothyroid patients may suffer from fatigue due to even mild thiamin deficiency. It’s common for those with thyroid dysfunction to experience absorption issues which can lead to poor thiamin utilization and subsequent deficiency.

The Role of Thiamin in Autoimmunity

Autoimmune thyroid disorders such as Hashimoto’s thyroiditis and Graves’ disease are among the leading causes of hypothyroidism and hyperthyroidism respectively. It has been found that people with autoimmune disorders may not be able to properly utilize thiamin. Studies suggest that enzymatic dysfunction or imbalance may contribute to poor thiamin processing at the cellular level. Therefore, if a patient is suffering from autoimmune thyroid disease, it is likely that their thiamin levels are reduced. This can further contribute to fatigue.

A study conducted in 2011 sought to investigate the connection between autoimmune dysfunction and the presence of thiamin deficiency. The study was composed of three Hashimoto’s patients who were treated with thyroid replacement therapies but continued to experience significant fatigue. After thiamin treatment was commenced, patients experienced partial or complete regression of their fatigue within a period of hours to days. The study concluded that administering high doses of thiamin helps balance and restore multiple thiamin-reliant processes, thereby eliminating various sources of fatigue.

The Safety of Supplementation

Thiamin has been shown to be an effective method for improving thyroid symptoms. If dietary restrictions keep you from eating food-based sources of thiamin, consider using a thiamin supplement. Supplementing with thiamin, even at greater levels, is considered safe. Because thiamin is water soluble, any excess remaining in the system is excreted through urine thereby avoiding potential toxicity. Furthermore, there are no reports of thiamin-related toxicity from supplementation or diet. This has lead the National Academy of Sciences to deem it unnecessary to give thiamin a Tolerable Upper Intake Level (UL).

Thiamin comes in a variety of forms and can be purchased as tablets, soft gels, lozenges, chewable vitamins, liquid drops, and in B-complex vitamin formulations. Vitamin B1 may also be listed as thiamin hydrochloride or thiamin mononitrates. Because of the many options available, people have the freedom to choose the ideal thiamin delivery method for them. We recommend HoltraCeuticals’ Mega B.

The only warning pertaining to thiamin supplementation is in the case of cancer treatment. Established cancers may sap the body’s stores of thiamin because it is a necessary part of cell proliferation. Therefore, providing greater levels of thiamin may accelerate the growth of certain cancers. If diagnosed with cancer or undergoing treatment for cancer, do not take thiamin unless directed by a physician.

The Thiamin Thyroid Relation

The thyroid and thiamin are mutually responsible for various functions including metabolic regulation and overall energy level. Therefore, it should not come as a surprise that thiamin plays a vital role in proper thyroid function and fatigue prevention.

If your thyroid has been treated and diet optimized but you still feel run down and overly tired on a regular basis, consider using a thiamin supplement to support your thyroid and get your energy back.

For even more information on thyroid health, read our Thyroid 101 e-book!

Click Here to Download Thyroid 101


1. Thiamine May Help Fatigue and Autoimmune Thyroid Disease. VeryWell.

2. Could thiamine be the fix for thyroid fatigue? Hypothyroid Mom.

3. Thiamine and Thyroid Fatigue. Dr. Izabella Wentz.

4. Thyroid and Thiamine. The National Academy of Hypothyroidism.

About Holtorf Medical Group

The Holtorf Medical Group specializes in optimizing quality of life and being medical detectives to uncover the underlying cause of symptoms, rather than just prescribing medications to cover-up the symptoms. We are experts in natural, prescription bioidentical hormone replacement and optimization, complex endocrine dysfunction, fibromyalgia, chronic fatigue syndrome and Lyme disease.

We’ve dedicated our practice to providing you the best in evidenced-based, integrative medicine that’s not only safe and effective, but provides measurable results.