Nutrients Required for Healthy Thyroid Function

Since the thyroid affects so many of the body’s systems and causes a variety of symptoms, it’s easy to see why there are so many nutrients involved in the thyroid cycle. The primary classifications of nutrients required for healthy thyroid function that we will discuss are 1. Fatty acids, 2. Amino acids, 3. Minerals, and 4. Vitamins. Each nutrient plays a part in either, thyroid hormone production, another nutrient’s synthesis, or hormone conversion.

The nutrient cycle of the thyroid is largely centered on the hormones that the thyroid produces: T4, T3, and calcitonin. In order for T4 and T3 to be produced, certain areas of the brain have to do their job first… The pituitary gland must release thyroid synthesizing hormone (TSH), and this release is dependent on the signaling of the pituitary gland by the hypothalamus with thyrotropin-releasing hormone (TRH). There is also a feedback loop, where the hormones send a signal to the brain not to release anymore TSH.

Thyroid Nutrient Cycle

TRH – We will begin the cycle with TRH, whose job is to stimulate the release of TSH from the pituitary gland and regulate metabolism and insulin sensitivity.1 The hypothalamus detects the amount of thyroid hormone available in the brain, and releases TRH to the pituitary gland. We see an underactive thyroid manifest as secondary hypothyroidism when a person has an insufficient amount of TRH, which is most often caused by thyroid tumors and the surgery or radiation used to treat them.2

TSH– After the neurons in the hypothalamus release TRH, it activates the release of TSH from the pituitary gland. TSH, then, stimulates the thyroid to release the thyroid hormones T4 & T3.

T4 – Tetraiodothyronine (T4) is the primary hormone produced by the thyroid and its production is triggered by TSH. It is called T4 because it is bound to four iodide molecules. It is considered to be the inactive form of thyroid hormone, and is converted to T3 when one of those iodine molecules is removed.

T3 – Triiodothyronine (T3) is the active form of thyroid hormone that can be produced directly by the thyroid, but mostly comes from the conversion of T4 to T3.

Negative Feedback Loop - T4 and T3 can then create a negative feedback loop on the pituitary gland, where high levels of T3 or T4 decrease TSH secretion and low levels of T3 or T4 increase the release of TSH.

Calcitonin – Calcitonin is another hormone produced by the thyroid. It is generally not considered a significant hormone because major diseases haven’t been reported to be affected by its production. This hormone reduces the amount of calcium in the blood by reducing the amount of calcium that your kidneys absorb and release back into the blood.3 It also counteracts parathyroid hormones that increase the amount of calcium in the blood. High levels of calcitonin may be an indicator of medullary thyroid cancer.4

Thyroid Nutrients

Amino Acids

We all know that amino acids are the building blocks of protein, but what could they possibly have to do with thyroid health? Well, amino acids have a huge part to play in the endocrine, cardiovascular, and central nervous systems that most do not realize. Amino acids are generally classified into two groups… not based on importance, but whether the body is capable of making them. Essential amino acids are not able to be synthesized by the body, so they must be ingested through the diet and include alanine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, and serine. Non-essential amino acids are still important, but the body is capable of making them. Some non-essentials that are important for thyroid health are tyrosine (which is synthesized from the amino acid phenylalanine) and cysteine (which is synthesized from methionine and serine).5

Asparagine and serine can effect TSH levels, while valine, leucine, and arginine have shown to affect serum levels of T4 and FT4.”6 and appropriate supplementation of the right amino acids can restore T3, T4, and TSH levels.5

Lysine deficiency can inhibit the activity and bioavailability of vitamin B6, which can interfere with the entire thyroid nutrient cycle through its effect on the regulation of pituitary hormones.7

The supplement N-acetyl cysteine can provide the body with cysteine, which supports proper glutathione production in the body. Glutathione levels can impact the TSH and thyroid antibody levels in patients with Hashimoto’s disease.8

Taking the wrong amino acids in the wrong amounts and without supportive nutrients can cause unintended negative consequences, and more appropriate direction can be obtained by scheduling a Thyroid Consultation to discuss personal dietary and supplement recommendations.

Fatty Acids

Fatty acids are also separated into essential and non-essential categories based on whether they are required to be taken in through diet. Most Americans are deficient in omega 3 fatty acids9, they are essential and required to be consumed in the food we eat. The most abundant types of omega 3 fatty acids are Alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). These fatty acids contribute to brain health, cardiovascular health, reduced inflammation, and have the potential to prevent certain cancers.10 In a study conducted on the diets of people with and without thyroid disease, the amount of omega 3 fatty acids that a person ingested was one of the strongest predictors of autoimmune thyroid disease.11

Minerals

Several minerals contribute to the health of the thyroid. Calcium, copper, iodine, iron, magnesium, manganese, selenium, and zinc are among the most significant contributors which may be lacking from the modern diet. 6

Calcium – One of the symptoms of thyroid dysfunction is changes in bone density and formation. This may be because of changes in bone metabolism caused by an imbalance in thyroid hormones, particularly calcitonin. Calcium supplementation may inhibit the absorption of thyroid medications like levothyroxine and reduce the absorption of hormone T4.12 Thyroid dysfunction can lead to osteoporosis and bone fractures, seen even in subclinical cases.13 It is important to get the right amount of calcium, but too much can cause it’s own set of problems.

Chromium - Those with autoimmune thyroid disease are often low in a large number of nutrients, including chromium, which is important for blood sugar regulation.14 Proper chromium levels may also reduce ones risk of thyroid tumor and goiter.15 Proper chromium supplementation may improve the insulin sensitivity of those with of type 2 diabetes and metabolic syndrome.16

Copper – One of the roles of copper in thyroid function is as a cofactor in the enzyme superoxide dismutase, which is necessary for thyroid function. Copper can also affect levels of T3 and T4, even when iodine intake is sufficient for their production.17

Iodine – We already know that the primary thyroid hormones have iodide molecule attached to them, and without sufficient iodine intake, they cannot be formed. Both, too little, and too much iodine can negatively affect the thyroid18. Supportive nutrients19 and body mass index may change how the body is able to absorb the iodine that is taken in.20

Iron – Another mineral whose deficiency is commonly seen in those with thyroid disorders is iron.21 The body requires iron to synthesize thyroid hormones, and thyroid hormones regulate the formation of blood cells.22 The underproduction of stomach acid seen in hypothyroidism or lack of B vitamins may also lead to a malabsorption of iron.

Selenium – Other than iodine, no other mineral has more of an effect on thyroid function than selenium, and selenium levels can be responsible for the body’s ability to absorb iodine. Selenium is also needed for TSH production, hormone production and release, the conversion of T4 to T3, and protects the thyroid against oxidative stress.17 Selenium supplementation can normalize thyroid hormone levels and lower thyroid antibodies even when the person’s selenium levels are in normal range.23

Zinc – Zinc plays a role in the function of several biological processes including immunity, metabolism, wound healing, and insulin sensitivity. In the thyroid, zinc is needed for hormone creation, T4 to T3 conversion, and the activity of hormone receptors.24 Zinc supplementation can mitigate hormone disruptions and cysts in women with polycystic ovarian syndrome (PCOS),25 and help the body to maintain efficient immune responses.26

Vitamins

Some of the vitamins involved in the thyroid nutrient cycle are vitamins A, B2, B6, B9, B12, C, D, and K. Whether your body is able to use the nutrients that it takes in may be dependent on dietary intake, absorption, and utilization. Generally, it is best to take in vitamins through food, but supplementation can provide a way to ensure proper nutrient levels in the event of imbalance.

Vitamin A – Vitamin A can ingested though food in two ways: directly from meat and eggs, or indirectly in vegetables containing carotenoids, which are then converted to vitamin A. Some people have difficulty converting carotenoids into active forms of vitamin A, and may struggle to maintain sufficient vitamin A levels.27 Vitamin A supplementation can affect how your body reacts to TSH and restore thyroid hormone levels, even when a person has subclinical (where thyroid levels appear in a normal reference range) thyroid dysfunction.28

*Super source: RDA of Vitamin A is 900-3,000 μg/day29 and about 1/4 cup of dried stinging nettle (Urtica diota) contains around 1250 μg.30

Vitamin B1 – Thiamine is a B vitamin that allows your body to produce energy from dietary carbohydrate intake, and deficiency may cause fatigue. The body only stores small amounts of this important vitamin, so it is essential that we intake it on a regular basis.

Vitamin B2 – Riboflavin is another B vitamin that is essential for the metabolism of energy. It is also an antioxidant, necessary for a healthy immune function. A deficiency can alter iron absorption and affect reproduction.31 Riboflavin is also responsible for the conversion of tryptophan to niacin, which then activates vitamin B6. Low thyroid hormones may also affect the activation of riboflavin.32 Supplementing this vitamin can increase red blood cell production and hemoglobin levels.31

Vitamin B3 – Much like the other B vitamins, niacin is able to produce energy from the breakdown of carbohydrates and fats. Supplementing niacin works to stabilize thyroid hormone levels and reduce free T4 concentrations by lowering thyroid-binding globulin.33

Vitamin B6 – Pyridoxine is another vitamin that those with thyroid dysfunction are commonly deficient in. The enzyme thyroid-hormone transaminase, which converts and activates thyroid hormones, is dependent on sufficient B6 levels.34 A deficiency in vitamin B6 also disrupts the production of serotonin, which affects cognition.35

Vitamin B9 – Genetic variations of the MTHFR gene may affect one’s ability to utilize folic acid, the synthetic form of folate, and are commonly seen in those with thyroid disease.36 Supplementation with folic acid has many benefits to health, including improving insulin resistance in type-2 diabetes.37

Vitamin B12 – A large portion of those with thyroid dysfunction are deficient in vitamin B12, particularly those with autoimmune hypothyroidism.38 Vitamin B12 deficiency may causes symptoms including fatigue, tremors, and neurological dysfunction.39 Supplementation with B12 has been shown to reduce neuro-degeneration and improve depressive symptoms.40

Vitamin C – Vitamin C is an essential vitamin for many body functions, including fertility and helps selenium to regulate iodine.41 It may also kill thyroid cancer cells and inhibit their production.42 It is a powerful antioxidant43 and may protect thyroid cells from oxidative stress. Low levels of vitamin C are seen in all types of thyroid disease, even in subclinical cases.44Supplementation of vitamin C can improve thyroid hormone levels and TSH concentrations.45

Vitamin D –Vitamin D deficiencies are common in those with autoimmune thyroid diseases like Hashimoto’s and Grave’s diseases.38 Supplementation may lower levels of thyroid antibodies and improve TSH levels.46

Vitamin K – Vitamin K is important for blood coagulation and bone metabolism, and thyroid hormone abnormalities may increase the amount needed by the body to normally clot the blood.47

Too Much Of A Good Thing?

We can see that the thyroid involves a complex array of nutrient and absorption factors to function optimally. Optimal nutrition is different for everyone, and too much of anything is not ideal for any body function. At Renewed Hope Nutritional Services, we can help to ease the complexity of thyroid health and the nutrients required to maintain it when you book a Thyroid Health Consultation.

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