Thyroid Support: Top Supplements You Should Know About

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Your thyroid is a small but mighty gland in your neck that plays a crucial role in your body’s metabolism, energy, and mood. When it’s out of balance, you can feel it in many ways, from fatigue to weight changes. The aim of this article is to provide some guidance through the maze of dietary supplements that can support your thyroid health. We’ll delve into various options, backed by peer-reviewed research, to help you make informed choices. Remember to consult with a registered dietitian or healthcare provider for personalized advice tailored to your specific needs.

Understanding Thyroid Function

The thyroid gland produces thyroid hormones that regulate a range of bodily functions, including your metabolism, heart rate, and body temperature. The main hormones it secretes are thyroxine (T4) and triiodothyronine (T3). These hormones travel through your bloodstream to receptors on every cell of the body and influence everything from how fast you burn calories to how quickly your heart beats.

When your thyroid is functioning well, it maintains a delicate balance of these hormones, keeping your body running smoothly. A malfunctioning thyroid can lead to hypothyroidism, where it produces too few hormones, or hyperthyroidism, where it produces too many. These conditions can greatly impact your overall health. Symptoms can range from weight gain or loss and fatigue to more severe complications like cardiovascular issues and mood disorders. The thyroid even plays a role in regulating your menstrual cycle, so its effects are truly wide-ranging.

Symptoms of Thyroid Imbalances

Thyroid imbalances can manifest as either hyperthyroidism, where the thyroid gland is overactive, or hypothyroidism, where the thyroid is underactive. Both conditions can have a significant impact on various bodily functions, and their symptoms can be quite distinct.

Symptoms of Hyperthyroidism

Hyperthyroidism occurs when the thyroid gland produces too much thyroid hormone, leading to an acceleration of the body’s metabolism. Common symptoms include:

  • Weight Loss: Unexpected weight loss, even when appetite and food intake remain normal or increase.
  • Increased Heart Rate: Rapid heartbeat (tachycardia) commonly over 100 beats per minute, palpitations, and arrhythmias.
  • Anxiety and Irritability: Nervousness, anxiety, and irritability are common.
  • Sweating: Excessive sweating and intolerance to heat.
  • Tremors: A fine tremor of the hands or fingers.
  • Fatigue and Muscle Weakness: Despite high energy levels, muscle weakness is common.
  • Sleep Disturbances: Difficulty sleeping.
  • Other Symptoms: Increased frequency of bowel movements, changes in menstrual patterns, and enlargement of the thyroid gland (goiter).

Symptoms of Hypothyroidism

Hypothyroidism occurs when the thyroid gland doesn’t produce enough thyroid hormones, slowing down the body’s metabolism. Common symptoms include:

  • Weight Gain: Unexplained weight gain is common, often despite a reduced appetite.
  • Fatigue: Persistent tiredness and lethargy.
  • Slow Heart Rate: A slower than normal heart rate.
  • Sensitivity to Cold: Increased sensitivity to cold temperatures.
  • Constipation: Digestive disturbances, often constipation.
  • Depression: Feelings of depression or low mood.
  • Muscle Weakness and Aches: General muscle weakness and aches.
  • Dry Skin and Hair: Dry, thinning hair and dry skin.
  • Eyebrow Changes: Loss of the outer third of the eyebrows.
  • Other Symptoms: Puffiness in the face, hoarseness, and impaired memory.

These symptoms can vary widely among individuals and can be subtle, especially in the early stages of thyroid dysfunction. Some symptoms may also overlap with other health issues, making thyroid imbalances sometimes difficult to diagnose based solely on symptoms. If you suspect a thyroid imbalance, it’s crucial to consult with a healthcare provider for appropriate testing and diagnosis.

Food Choices and Lifestyle Factors That Affect The Thyroid

Nutrients play a critical role in thyroid function. For instance, iodine is a key ingredient that your thyroid needs to produce hormones. It’s often added to table salt to ensure people get enough in their diet to prevent goiter. Selenium, another important mineral, aids in the conversion of T4 to the more active T3 hormone and also protects the thyroid from oxidative stress. Zinc, iron, and vitamin D also contribute to healthy thyroid function by supporting metabolism, hormone production, and immune health, respectively.

Your food choices can have a direct impact on thyroid health. Consuming foods rich in these nutrients can support optimal thyroid function. On the flip side, deficiencies in these nutrients can lead to thyroid issues. For example, an iodine deficiency can result in an enlarged thyroid gland, also known as a goiter, and may eventually lead to hypothyroidism. Foods like fish, dairy, and fortified grains are generally good sources of these essential nutrients. In contrast, certain foods known as goitrogens, such as raw cruciferous vegetables, can interfere with iodine uptake and should be consumed in moderation if thyroid function is a concern.

The Benefit of A Gluten-Free Diet

In managing thyroid disorders, understanding the impact of gluten is crucial. Gluten is found in wheat, barley, and rye. It can be immunogenic, triggering an immune response, especially in people with autoimmune thyroid disorders such as Hashimoto’s thyroiditis. Gluten is a problem for those with celiac disease, where gluten damages the intestine, and non-celiac gluten intolerance.

However, gluten can also increase intestinal permeability, commonly known as ‘leaky gut,’ allowing particles to enter the immune system and bloodstream where they cause an immune response. The main concern for people with Hashimoto’s is the possibility of molecular mimicry, where the immune system, responding to gluten, might mistakenly target thyroid tissue due to structural similarities. Essentially, the immune system mistakes thyroid tissue for the gluten it is trying to destroy. This cross-reaction can worsen autoimmune thyroid conditions, leading to further thyroid dysfunction.

Research as well as anecdotal evidence supports improvements in symptoms and antibody levels for some people with autoimmune thyroid disorders on a gluten-free diet but responses can vary.

Hashimoto’s thyroiditis (HT) is the most common autoimmune disease. HT may be associated with nonthyroidal autoimmune diseases, including celiac disease (CD) or other gluten-related conditions…The meta-analyses showed reduction in antibody levels … Our results seem to indicate a positive effect of the gluten deprivation on thyroid function and its inflammation, particularly in patients with Hashimoto’s and Gluten Related Conditions. 

Effect of gluten-free diet on autoimmune thyroiditis progression in patients with no symptoms or histology of celiac disease: a meta-analysis [PMC10405818]

Exercise and Stress Management

Physical activity is not only good for your overall health, but it can also help regulate thyroid function. Exercise boosts metabolism, aids in weight loss, and can improve hormone levels, including those that affect the thyroid. Stress management techniques such as deep breathing, meditation, and other relaxation practices can also help. Chronic stress can adversely affect the thyroid by disrupting hormone levels and exacerbating thyroid problems. So managing stress effectively can go a long way in supporting your thyroid health.

The Iodine Controversy

The controversy over iodine supplementation, particularly the recommended doses, has been a subject of debate within the medical and nutritional community. The disparity between the relatively high dose of 12.5 milligrams (mg) and the much lower recommended daily allowance (RDA) of around 150-170 micrograms (mcg) for adults highlights this debate. Understanding this controversy involves looking at both historical incidents of harm from iodine and the theories advocating high doses.

Historical Incidents of Harm from Iodine:

  • Iodine Excess and Thyroid Dysfunction: Excessive iodine intake has been linked to thyroid dysfunction, including both hyperthyroidism and hypothyroidism. These conditions can arise due to the thyroid’s response to high levels of iodine, particularly in individuals with pre-existing thyroid issues or iodine sensitivity.
    • High iodine intakes are well tolerated by most healthy individuals, but excess iodine intakes may precipitate hyperthyroidism, hypothyroidism, goiter, and/or thyroid autoimmunity. [PMID: 30891786]
  • Iodine-Induced Thyrotoxicosis: There have been historical instances, such as in Japan, where high dietary iodine intake (often from seaweed) led to thyrotoxicosis, a condition characterized by an overactive thyroid gland.

Theory That High Doses Are Sometimes Needed:

  • Detoxification: Some theories suggest that higher doses of iodine can help detoxify the body, particularly from heavy metals and halogens like fluoride and bromide.
  • Breast Health: There is a viewpoint that higher iodine doses can be beneficial for breast health, although this is not widely supported by mainstream medical research.

Current Medical Consensus:

The prevailing medical consensus advocates for a balanced approach to iodine intake, aligning with the RDA of 150-170 mcg for most adults. This stance is based on research indicating that this level is sufficient for maintaining thyroid health without the risks associated with higher intake.

In summary, while there are historical and theoretical bases for both low as well as high-dose iodine supplementation, the scientific evidence and medical consensus currently support lower intake at 150-170 mcg for most adults. The need for high-dose supplementation is not well-substantiated in the broader medical community. People considering iodine supplementation at higher doses should consult with healthcare professionals to weigh the benefits and risks, considering their specific health circumstances.


Dietary supplements are not designed to diagnose, treat, cure, or prevent any disease. This article aims to offer valuable insights into which nutritional supplements have undergone scientific study and shown promise in supporting specific health conditions. We break down the research, so you can work with your medical providers to make informed decisions about adding supplements to your health regimen. For personalized advice tailored to your needs, we recommend consulting with a registered dietitian in addition to your primary care provider.

Check with your physician when adding supplements. While supplements are generally safe for most people, do not add nutritional supplements without your physician’s specific approval if you are pregnant or nursing, are undergoing cancer treatment, have a history of organ transplant, liver or kidney disease, or take medications that interact with supplements.


Benefits of Nutritional Supplements for Thyroid Support

While dietary supplements are not designed to diagnose, treat, cure, or prevent any disease, this article aims to offer valuable insights into which nutritional supplements have undergone scientific study and have shown promise in supporting thyroid conditions.

Here’s the research, so you can make informed decisions about adding supplements to your health regimen. For personalized advice tailored to your needs, we strongly recommend consulting with your medical provider and registered dietitian nutritionist in the selection of nutritional supplements.

Supplements that are shown to be important for thyroid function include:

  • Multivitamin: Multivitamin will include vitamins and minerals that are important for thyroid function.
    • Vitamin D: Vitamin D has implications for bone health and the immune system. In terms of thyroid health, adequate levels of vitamin D may help regulate the immune response and could be beneficial in autoimmune thyroid conditions like Hashimoto’s or Graves’ disease. Vitamin D receptors are found in the cells of the immune system and may play a role in preventing excessive immune reactions that could harm the thyroid. [PMC8877323]
    • Iodine: Iodine plays an indispensable role in thyroid health because it’s a primary ingredient in the production of thyroid hormones T3 (triiodothyronine) and T4 (thyroxine). When you consume iodine, it’s absorbed into your bloodstream and travels to the thyroid gland, where it becomes a building block for these crucial hormones. A deficiency in iodine can lead to issues such as hypothyroidism and even goiter, an abnormal enlargement of the thyroid gland. Intake varies widely across the population. [PMID: 28322679]
    • Selenium: This essential mineral performs multiple roles in supporting your thyroid. It’s integral in the enzymatic reaction that converts the less active T4 hormone into the more active T3 form. Furthermore, selenium acts as an antioxidant, protecting the thyroid gland from harmful oxidative stress and potential damage. This protective feature could be beneficial for conditions like Hashimoto’s thyroiditis, an autoimmune disease affecting the thyroid. [PMC10080082]
    • Zinc: Zinc contributes to the conversion of T4 into T3 in the liver, optimizing your thyroid hormones into their most active form. This conversion is essential for regulating metabolism, energy levels, and mood. Additionally, zinc plays a role in the functioning of thyroid receptors, which exist in cells throughout your body, helping to ensure that thyroid hormones do their job effectively. [PMID: 35532055]
  • Ashwagandha: Known as an adaptogen, ashwagandha helps the body adapt to stress, which can be particularly beneficial for thyroid health. It has been studied for its ability to regulate thyroid hormones and can be useful in both low (hypothyroidism) and high (hyperthyroidism) thyroid conditions. Ashwagandha seems to enhance T4 levels, thus making it easier for the body to convert this into the more active form, T3. [PMID: 37013429]
  • Myoinositol: A study found that the combination of myo-inositol and selenium reduced thyroid antibody levels in patients with Hashimoto’s thyroiditis, while also increasing fT3 and fT4 levels and improving quality of life, effectively restoring normal thyroid function. [PMC5331475]

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Supplement and Safety Details

When it comes to thyroid support, the supplements Iodine, Selenium, Zinc, Vitamin D, and Ashwagandha are generally considered safe for most people when used appropriately. Each of these supplements plays a specific role in thyroid function, from hormone production to immune system regulation. However, like most supplements, they can interact with medications or other supplements, and excessive doses can lead to unwanted side effects.

Medication Interactions

  • Iodine: Can interact with thyroid medications, potentially affecting thyroid function, and should be used cautiously in people with thyroid disorders.
  • Selenium: May interact with chemotherapy drugs and can affect the body’s ability to use certain medications used to lower cholesterol.
  • Zinc: Can reduce the effectiveness of certain antibiotics and may interact with diuretics and arthritis medications.
  • Vitamin D: High doses can interact with steroids, weight loss drugs, and certain heart medications, affecting their efficacy.
  • Ashwagandha: Can interact with thyroid, blood sugar, and blood pressure medications, potentially affecting their effectiveness.

Supplement Interactions

  • Iodine: Can interact with other minerals like copper and selenium, potentially disrupting the balance of these trace elements in the body.
  • Selenium: High doses of selenium may interfere with the absorption and effectiveness of other antioxidants like vitamin C and vitamin E.
  • Zinc: Can compete with copper and iron for absorption in the body, potentially leading to deficiencies of these minerals if taken in high doses.
  • Vitamin D: When taken in high doses, it can affect the metabolism of magnesium and calcium, potentially leading to imbalances.
  • Ashwagandha: Can increase the sedative effects of supplements that promote relaxation, possibly leading to increased drowsiness. These include Valerian Root, Magnesium, Ashwagandha, L-Theanine, Chamomile, Passionflower, Lemon Balm, CBD Oil, Melatonin, and GABA.

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Types of Labs to Consider

Thyroid labs are available, but interpretation is complex, so consult with a healthcare provider to decide which labs are most relevant for your specific health concerns.

  • TSH (Thyroid Stimulating Hormone) Test: Physicians often use this test as a screening tool for thyroid function and to adjust medication dosages. While TSH levels alone don’t give a complete picture, they’re a useful starting point for understanding thyroid health.
  • Free T3 and Free T4 Tests: These tests measure the levels of active thyroid hormones in your blood. Understanding the balance between T3 and T4 can provide a more nuanced view of thyroid health and are key for pinpointing whether you’re dealing with conditions like hypothyroidism or hyperthyroidism.
  • Thyroid Antibody Tests: These tests help identify autoimmune conditions affecting the thyroid. For Hashimoto’s disease, thyroid peroxidase (TPO) antibodies are often present. In Graves’ disease, the test may measure Thyroid thyroid-stimulating immunoglobulins (TSIs) which are indicative of the condition. These tests are crucial for confirming autoimmune thyroid issues.
  • Micronutrient Tests for Selenium, Zinc, etc.: These tests measure essential minerals that impact thyroid function. Knowing your selenium and zinc levels can help guide your dietary choices and determine if supplementation might be necessary.

The NutriScape Lab Shop includes a Comprehensive Thyroid Lab that tests for TSH, free T3 and T4, total T3 and T4, and antibodies including thyroglobulin and thyroid peroxidase.

Food First!

Although this article discusses supplements in detail, don’t forget that we are absolutely committed to the “Food First” approach to nutrition. When it comes to your health, the totality of your eating habits far surpasses the impact of individual nutrients or any single supplement you consume. Even though this article doesn’t delve into the broader picture of your overall diet, it’s crucial to keep this element at the forefront of our minds. Your food needs to provide all the vitamins, minerals, fiber, and phytochemicals to nourish your body systems down to the cellular level.

Food choices, rather than supplements, are the most critical factors for a healthy gut microbiome. These trillions of tiny inhabitants in your gut affect your brain waves; they orchestrate your immune system. They possess the power to create molecules that can switch genes on or off and are even capable of synthesizing neurotransmitters. Opting for organic foods and steering clear of plastic packaging (including those labeled BPA-free) is a smart move to limit toxin exposure. The sum of all these parts leads to a powerful conclusion: the ultimate key to your health lies in the quality and balance of the food you consume. Supplements are secondary.

To Sum It Up

Navigating the world of nutritional supplements for thyroid support can be overwhelming, but the good news is there are scientifically-backed options that can make a real difference. From essential minerals like Iodine, Selenium, and Zinc to other supportive nutrients like Vitamin D, and Ashwagandha, these supplements offer a variety of ways to improve thyroid health. Remember, supplements are most effective when used as part of a broader health strategy that includes a balanced diet and lifestyle. For tailored recommendations that suit your specific needs beyond prescribed medication, consult a registered dietitian. They can provide expert advice and help you make informed choices to support your thyroid and overall well-being.


This Article is Not a Substitute for Medical Advice

Dietary supplements are not designed to diagnose, treat, cure, or prevent any disease. The Supplement Sciences website seeks to provide comprehensive access to the most relevant supplement information along with convenient online ordering. We do not provide medical advice and cannot guarantee that every product suggested is completely without risk. Since each person is unique in their health history and medication use, it is important to discuss supplements with your personal physician. Specifically, pregnant women and individuals being treated for cancer or liver or kidney problems must consult their physician about every nutritional supplement they plan to take. People taking medications for the treatment of HIV or with a history of organ transplant must not take supplements without consulting with their physician.


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