The thyroid is an unsung hero for most people, with this small gland having a big impact on healthy bodily functions. But, sometimes it can stop working properly. These thyroid disorders are relatively common, with women having a higher tendency to develop thyroid issues¹. 

To help manage symptoms, there are a range of medical interventions. But there is also research to suggest that certain supplements may help to support thyroid health. In this guide, we’ll cover everything you need to know: from what the thyroid actually is and its role in the body, to everything you need to know about thyroid supplements…

What is the thyroid?

But first, what do you already know about the thyroid? Considering that it’s actually pretty important for your growth and metabolism, most of us don’t tend to know a lot about it. 

So, we’re going to start with the basics - like where is your thyroid?

The thyroid gland is in your neck, just below your larynx (voice box). It’s usually described as butterfly-shaped because it’s made up of two lobes that sit on either side of the trachea (windpipe). These are connected by a thin bridge of thyroid tissue called the isthmus². 

Your thyroid is part of the endocrine system. The endocrine system³ manages your hormones, and is in charge of the production, release, and regulation of various hormones that your body needs to function properly. Hormones themselves are a kind of chemical messenger, carrying information and messages through the body to areas that need them, and telling them what to do, and when. 

The thyroid is responsible for producing and releasing several hormones, which are⁴:

• Thyroxine: abbreviated to T4, thyroxine is the main hormone your thyroid makes. However, it has little impact on your body until it’s converted into triiodothyronine.

• Triiodothyronine: also referred to as T3, this is the form of thyroxine that your metabolism uses for regulation.

• Reverse triiodothyronine: this hormone, also known as RT3, reverses the effect of T3. 

• Calcitonin: as the name suggests, this helps to regulate your calcium levels. 

Note: we’ll explore what exactly these hormones do in a bit more detail below.

However, the thyroid doesn’t work alone. Instead, it receives signals from the pituitary gland (which is found in the brain), to produce more or less thyroxine and triiodothyronine.

What does the thyroid do?

So we know where it is, and that it produces hormones: but what does the thyroid do?

Your thyroid, thyroxine, and triiodothyronine, play an important role in various bodily processes, but are mostly involved with metabolism, and growth (in children).

Metabolism refers to how your body uses energy on a cellular level⁵. This involves catabolism, where food is broken down into its component parts; and anabolism, which uses these molecules to build more complex substances. A high metabolism makes energy quickly, whilst a low metabolism is much slower. The hormones produced by your thyroid are involved with this process, helping to regulate the speed in which you produce energy.

The thyroid is also involved in⁶:

• Regulating your body temperature.

• Managing your breathing and digestion.

• Skin and bone health and maintenance.

• Fertility regulation.

• Supporting brain development and mental activity.

Note: in children, the thyroid is essential for proper growth and development. All babies in the UK are tested for congenital hypothyroidism shortly after birth with a heel prick blood test⁷.

Types of thyroid disorders

For most people, the thyroid works as intended, and there’s not really anything you need to think about; just maintain a healthy diet, and exercise regularly.

However, there are occasions where things go awry. When this happens, you can develop a thyroid disorder, which can usually be categorised through overactivity or underactivity.

Hypothyroidism (underactive thyroid)

Hypothyroidism is also known as an underactive thyroid. This is because your thyroid is not producing enough thyroxine and triiodothyronine, which affects how well your body can function. Common symptoms of an underactive thyroid include⁸:

• Extreme tiredness and fatigue.

• Reduced resistance to cold (feeling the cold more).

• Otherwise unexplained weight gain.

• Constipation.

• Trouble concentrating or thinking clearly (aka brain fog).

• Depression or increased low mood.

• Dry skin and hair, or hair loss.

• A croaky voice.

• Irregular, or heavier, periods (if you menstruate).

These symptoms tend to grow over time, and you may experience a mixture over time.

Diagnosis: if you experience a selection of these symptoms, your doctor will often feel around your neck to find out if you have a swollen thyroid. You may also have blood tests to check the levels of T3 and T4 in the blood.

An underactive thyroid may occur for a range of reasons. The main cause in the UK is a condition called Hashimoto’s Disease⁹. This is an autoimmune condition that causes your immune system to attack your thyroid gland, preventing it from producing enough T3 and T4. 

In this context, we’d like to highlight that blood tests for thyroid antibodies - mainly anti-thyroid peroxidase (Anti-TPO) and anti-thyroglobulin (Anti-Tg) - are used to detect autoimmune thyroid disease. However, many NHS GP services test only TSH (thyroid-stimulating hormone) - which is why many people opt for private antibody testing to get a quicker or more complete panel.

Note: functionally, a TSH value above 2.1 is considered the beginning of hypothyroidism. 

Other causes of hypothyroidism include:

• Having an associated condition, like thyroiditis. This is where the thyroid gland becomes inflamed, and is unable to release enough hormones into the body¹⁰.

• Surgery on or around the neck and thyroid, including the removal of the thyroid (a partial or total thyroidectomy).

• Radiotherapy on or around the neck and thyroid.

• Incorrect dosing for an overactive thyroid.

• Insufficient iodine in the diet (however, this is rare in the UK).

• Certain medical treatments, such as drugs for diabetes, lithium-based mood-stabilisers, etc¹¹. These drugs can suppress thyroid function.

• HLA genetics can also be a common cause of hypothyroidism - akin to what causes Coeliac disease. 

The majority of the time, an underactive thyroid is treated with a medicine called levothyroxine. This helps to top up poor function, or replaces hormone production entirely in the case of a total thyroidectomy.

Hyperthyroidism (overactive thyroid)

At the opposite end of the spectrum, you can develop an overactive thyroid (or hyperthyroidism). This is, as the name suggests, where the thyroid is working too well, and produces too much T3 and T4. This results in symptoms like¹²:

• Mood swings, and increased nervousness, anxiety, and irritability.

• Trouble sleeping.

• Persistent tiredness, and feelings of weakness in the body.

• Increased sensitivity to heat.

• Swelling in the neck (an enlarged thyroid gland or goitre).

• Heart palpitations (an irregular or faster than usual heartbeat).

• Twitching and trembling.

• Unexplained or sudden weight loss.

As with an underactive thyroid, you may experience a selection of these symptoms over time.

Hyperthyroidism can be caused by a number of different factors¹³.

Graves’ Disease is the most common cause of hyperthyroidism, with around 4 in 5 cases attributed to it¹⁴. Like Hashimoto’s in that it’s an autoimmune disorder, with Graves’ Disease, instead of attacking the thyroid, the body produces antibodies that stimulate thyroid hormone production.

Less commonly, you can develop nodules on the thyroid. These can contain thyroid tissue, which increases the amount of hormones produced. These nodules are typically benign, and tend to affect people over 60 (but not always). Cancerous nodules are much rarer: only around 5 in 100 thyroid lumps are cancerous¹⁵.

You may also develop an overactive thyroid if you have too much iodine in your diet, i.e. in certain medications, such as amiodarone (which is used to treat heart arrhythmias). Iodine is essential for the production of T3 and T4, and too much can cause overproduction¹⁶. You may also develop thyroiditis (or swelling of the thyroid), which can cause your body to produce too much T3 and T4. In both of these cases, your body will tend to go back to normal once the inflammation has died down, or stop/change medications.

Diagnosis: if doctors believe the issue may be your thyroid, they will usually arrange a blood test. In hyperthyroidism, the thyroid is producing too much thyroid hormone. High circulating T4/T3 suppress the pituitary’s release of TSH by negative feedback, so TSH falls and is often very low or undetectable. From here, you may have further tests to understand the underlying cause. 

There are a range of treatments for an overactive thyroid, depending on the severity of the condition. Treatment tends to be one of three options, which are¹⁷:

• Medication: medications called thionamides stop your thyroid from producing excess amounts of thyroid hormones. This is typically taken for around 12-18 months, and you may be prescribed beta blockers as a short-term measure to manage symptoms. If the issue resolves, you can be slowly weaned off of the medicine. However, in some cases, you may need to take these for the rest of your life.
  

• Radioactive iodine treatment: in this treatment, patients are given a drink or capsule containing iodine and a small amount of radiation, which is absorbed by your thyroid. This destroys cells in the thyroid, which reduces its output. Most only need a single dose to cure an overactive thyroid.
  

• Surgery: finally, you may be advised to have some or all of your thyroid completely removed via surgery. This is called a partial or total thyroidectomy, and may be the best option for a number of reasons:

• The gland is severely swollen due to a large lump or goitre.

• Less invasive treatments aren’t an option for you, or your symptoms keep returning after trying them.

Supplement ingredients for thyroid disorders

For most people, maintaining a healthy and balanced diet is enough to maintain a healthy bodily equilibrium. But, sometimes you need some extra support from supplements - including when you have a thyroid disorder. 

Below, we’ve picked out several minerals, extracts, and active ingredients that can help to manage and support a healthy thyroid.

L-Tyrosine

Tyrosine is a key amino acid in thyroid function, and supplementation may be useful for people with hypothyroidism to support hormone production¹⁸. L-Tyrosine also supports the production of thyroglobulin - the large precursor protein from which T4 and T3 are cleaved.

Olive leaf extract

Whilst the exact method of action is unknown, research suggests that olive leaf extract could ‘stimulate thyroid function’¹⁹. Some scientists speculate that olive leaf extract may assist the thyroid primarily through its active compound oleuropein - which has powerful antioxidant properties. 

L-BAIBA

Also known as β-aminoisobutyric Acid, L-BAIBA has been linked to reducing inflammation and fat metabolism in the body²⁰. It is thought that L-BAIBA supports thyroid function indirectly through mitochondrial, metabolic, and hormonal pathways. 

Schizandra Root

Research suggests that Schizandra Root can contribute to the number and volume of thyroid nodules²¹. Schizandra Root also supports liver function - which is the main site of T4 to T3 conmversion.

Guggul extract

A traditional part of Ayurvedic medicines, studies have shown that Guggul Extract has thyroid-stimulatory properties (through encouraging the uptake of iodine in the body)²². Arguably, the most important function of Guggul Extract is its effect on thyroid hormone synthesis - boosting thyroxine (T4) production.

Capsaicinoids

Currently in the early stages, nevertheless, research suggests that capsicum annuum could have thyroid-stimulatory properties to help support and improve thyroid function²³. Further, it is believed that capsaicinoids can increase your body’s metabolic rate - reducing the burden on your thyroid. 

Coleus Forskohlii Extract

Research has shown that forskolin, which is the main biologically active phytoconstituent in the coleus forskohlii plant, increases the production and release of thyroid hormones²⁴.  On a more detailed level, Coleus Forskohlii Extract can directly increase cyclic AMP - a key secondary messenger for thyroid-stimulating hormone (TSH). 

Paradoxine

A patented form of Grain of Paradise extract, early research suggests that this ingredient may help to elevate T3 and T4 levels in the body. It’s also an anti-inflammatory²⁵. It is also speculated that Paradoxine may increase thermogenesis - reducing the metabolic load on the thyroid. 

Copper Bisglycinate

Copper has been linked to maintaining thyroid function in a selection of ways, from preventing T4 overabsorption to stimulating hormone production²⁶. Copper is also integral in the production of thyroid hormones. It also works in tandem with Iodine to support proper thyroid physiology. 

Manganese Gluconate

Early research suggests that manganese is important for maintaining thyroid hormone homeostasis (the balance of hormones in the body)²⁷. Manganese Gluconate is also required for the synthesis of T4. 

Folinic Acid

Studies have shown that Folinic Acid, a form of folic acid, in combination with levothyroxine, can help to reduce levels of homocysteine in the body. Elevated levels of homocysteine has been related to an increased risk of cardiovascular disease²⁸. Folic Acid also supports methylation - which is crucial for thyroid-hormone metabolism.

Selenium Monomethionine

Selenium is an important part of thyroid hormone synthesis, and lower serum levels have been linked to the “newly diagnosed Graves’ disease and autoimmune hypothyroidism”²⁹. Selenium can also protect the thyroid from oxidative damage, and supports healthy TSH feedback signalling.

Molybdenum Amino Acid Chelate

Molybdenum is associated with thyroid metabolism and thyroid hormone levels³⁰. Molybdenum also supports the detoxification pathways that protect the thyroid from oxidative damage, as well as reducing the burden of environmental goitrogens (substances that can interfere with the thyroid’s ability to produce hormones). 

Vitamin B12 (methylcobalamin)

Research suggests that there is an association between low levels of vitamin B12 and hypothyroidism³¹. Vitamin B12 also supports healthy methylation (which is, of course, essential for thyroid-hormone metabolism). It also supports red blood cell formation, which is critical to thyroid hormone delivery.

Iodine

As we’ve mentioned previously, iodine is essential for thyroid hormone production. Insufficient iodine levels can “impair thyroid function” and “lead to goiters” and “is responsible for hypothyroidism due to a lack of the substrate for the synthesis of thyroid hormone”³² Basically, this means that your body needs iodine to make T3 and T4. However, too much iodine can potentially cause an overactive thyroid (as it makes too much), so it’s important to monitor the levels in your supplements.

On this point, please be aware that kelp and other seaweed supplements are an unreliable source of Iodine - precisely because Iodine content can vary wildly between species and batch (from tens to thousands of micrograms per gram). For this reason, many UK dietetic and thyroid charities advise against using kelp/seaweed supplements as a routine Iodine source. 

Here at Supplement Needs, our Thyroid Stack only uses 7mcg of Iodine in a controlled manner from Potassium Iodide.

Supplement Needs Thyroid Stack: why choose us?

Buy Now

When it comes to supporting your health, you deserve the best. And, while we may be biassed, we truly believe that the best is the Supplement Needs Thyroid Stack. Why?

• 🔍 Complete ingredient transparency: we strongly advocate for total ingredient transparency in all of our products. So, not only do we tell you exactly what ingredients are in our supplements, we also explain how much, and (where applicable) the provenance of the ingredient - from root to leaf. 

• 💯 Superior ingredient quality: you will never find “filler” ingredients in our supplements. Everything we include serves a purpose. Plus, we always use the patented or superior form of an ingredient where possible to ensure maximum quality. For example, in Thyroid Stack, this includes the chelated Molybdenum, or Aframols® form of paradoxine.

• 🎓 Expert knowledge and research-backed formulation: our Thyroid Stack is researched and developed by renowned industry expert Dr Dean St Mart PhD, and is built around practical, evidence-based choices at every step.

• 🏭 Excellent manufacturing standards: our Thyroid Stack (like all of Supplement Needs’ products), is manufactured in line with GMP/ISO 22000 standards, meaning it meets the highest-possible quality standards to ensure an excellent final product.
  

Discover our Health collection at Supplement Needs

Whether you’re managing an underactive or overactive thyroid, or simply looking to optimise your long-term health, choosing the right supplements matters. At Supplement Needs, every formulation is created with a single purpose: to provide you with uncompromising, research-backed support you can trust.

Shop the Supplement Needs Thyroid Stack now

For more information and insights into supplements, explore the Supplement Needs blog…

Could a Vitamin Deficiency Be Making You Tired? | What are the Best Supplements for High Blood Pressure? | What are the Best Supplements for Women over 40?

Disclaimer

The information on this website should not be used as a substitute for professional medical care or advice. If you have any questions about your health, please contact your doctor.

References:

1. NHS Online, 2023, ‘Overview: Overactive Thyroid (hyperthyroidism). Available from: https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/. Accessed on 24th November 2025. 

2. British Thyroid Foundation, 2025, ‘Your thyroid explained’. Available from: https://www.btf-thyroid.org/what-is-thyroid-disorder. Accessed on 24th November 2025.

3. Cleveland Clinic Online, 2023, ‘Endocrine System’. Available from: https://my.clevelandclinic.org/health/body/21201-endocrine-system. Accessed on 26th November 2025.

4. Cleveland Clinic Online, 2022, ‘Thyroid’. Available from https://my.clevelandclinic.org/health/body/23188-thyroid. Accessed on 25th November 2025.

5. Sánchez López de Nava, A., & Raja, A., 2022, ‘Physiology, Metabolism’, StatPearls [Internet]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK546690/. Accessed on 26th November 2025.

6. Cleveland Clinic Online, 2022, ‘Thyroid’. Available from https://my.clevelandclinic.org/health/body/23188-thyroid. Accessed on 25th November 2025.

7. GOSH Online, 2015, ‘Congenital hypothyroidism’. Available from: https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/congenital-hypothyroidism/. Accessed on 26th November 2025.

8. NHS Online, 2025, ‘Underactive thyroid (hypothyroidism)’. Available from: https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/. Accessed on 24th November 2025.

9. ibid.

10. Cleveland Clinic Online, 2022, ‘Thyroiditis’. Available from: https://my.clevelandclinic.org/health/diseases/15455-thyroiditis. Accessed on 26th November 2025.

11. Thyroid UK, 2022, ‘Food and Drug Interactions’. Available from: https://thyroiduk.org/food-and-drug-interactions/. Accessed on 26th November 2025.

12. NHS Online, 2023, ‘Overview: Overactive thyroid (hyperthyroidism)’. Available from: https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/. Accessed on 24th November 2025.

13. NHS Online, 2023, ‘Causes: Overactive thyroid (hyperthyroidism)’. Available from: https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/causes/. Accessed on 24th November 2025.

14. NHS Online, 2023, ‘Causes: Overactive thyroid (hyperthyroidism)’. Available from: https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/causes/. Accessed on 24th November 2025.

15. Cancer Research UK, 2023, ‘Referral to a specialist for symptoms of thyroid cancer’. Available from: https://www.cancerresearchuk.org/about-cancer/thyroid-cancer/getting-diagnosed/referral-specialist. Accessed on 26th November 2025.

16. InformedHealth.org [Internet], 2024, ‘In brief: How does the thyroid gland work?’. Available from https://www.ncbi.nlm.nih.gov/books/NBK279388/. Accessed on 26th November 2025.

17. NHS Online, 2023, ‘Treatment: Overactive thyroid (hyperthyroidism)’. Available from: https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/treatment/. Accessed on 24th November 2025.

18. Redmer, J., 2014, (Minichiello, V., updated 2020), ‘Hypothyroidism’, VA office of Patient Centered Care and Cultural Transformation. Available from: https://www.va.gov/WHOLEHEALTHLIBRARY/docs/Hypothyroidism.pdf. Accessed on 26th November 2025.

19. Pang, K-L., Lumintang, J.N., & Chin, K-Y., 2021, ‘Thyroid-Modulating Activities of Olive and Its Polyphenols: A Systematic Review’, Nutrients, 13(2):529. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC7915253/. Accessed on 26th November 2025.

20. Yi, X., et al., 2023, ‘Signaling metabolite β-aminoisobutyric acid as a metabolic regulator, biomarker, and potential exercise pill’, Front Endocrinol (Lausanne), 14:1192458. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10258315/. Accessed on 26th November 2025.

21. Cheng, C-Y., et al., 2024, ‘Traditional Chinese medicine treatment for benign thyroid nodules: Literature review’, Tzu Chi Med., 36(2):142-151. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11025596/. Accessed on 26th November 2025.

22. Kunnumakkara, A.B., et al., 2018, ‘Googling the Guggul (Commiphora and Boswellia) for Prevention of Chronic Diseases’, Front Pharmacol., 9:686. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6087759/. Accessed on 26th November 2025.

23. Elwan, H., et al., 2020, ‘Efficacy of Dietary Supplementation with Capsicum Annum L on Performance, Hematology, Blood Biochemistry and Hepatic Antioxidant Status of Growing Rabbits’, Animals., 10(11):2045. Available from: https://www.mdpi.com/2076-2615/10/11/2045. Accessed on 26th November 2025.

24. Singh, S., et al., 2020, ‘Protective effect of a polyherbal bioactive fraction in propylthiouracil-induced thyroid toxicity in ratsby modulation of the hypothalamic–pituitary–thyroid and hypothalamic–pituitary–adrenal axes’, Toxicol Rep., 7:730–742. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC7301176/. Accessed on 26th November 2025.

25. Yi, G., et al., 2025, ‘A 90-day oral toxicity study of Grains of Paradise Extract’, Archives of Clinical Toxicology, 7(1):77-87. Available from: https://www.probiologists.com/article/a-90-day-oral-toxicity-study-of-grains-of-paradise-extract. Accessed on 26th November 2025.

26. Zhou, Q., et al., 2022, ‘Trace elements and the thyroid’, Front Endocrinol (Lausanne), 13:904889. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9637662/. Accessed on 26th November 2025.

27. Wróblewski, M., et al., 2023, ‘The Role of Selected Trace Elements in Oxidoreductive Homeostasis in Patients with Thyroid Diseases’, Int J Mol Sci., 24(5):4840. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10003705/. Accessed on 26th November 2025.

28. Ziaee, A., et al., 2012, ‘Effects of folic acid plus levothyroxine on serum homocysteine level in hypothyroidism’, Caspian J Intern Med., 3(2):417–420. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC3861905/. Accessed on 26th November 2025.

29. Zhou, Q., et al., 2022, ‘Trace elements and the thyroid’, Front Endocrinol (Lausanne), 13:904889. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9637662/. Accessed on 26th November 2025.

30. ibid.

31. Benites-Zapata, V.A., et al., 2023, ‘Vitamin B12 levels in thyroid disorders: A systematic review and meta-analysis’, Front Endocrinol (Lausanne), 14:1070592. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9994182/. Accessed on 26th November 2025.

32. Zhou, Q., et al., 2022, ‘Trace elements and the thyroid’, Front Endocrinol (Lausanne), 13:904889. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9637662/. Accessed on 26th November 2025.