Important nutrients for Hashimoto’s and hypothyroidism
As the master of metabolism, the thyroid gland regulates digestion, energy production, mental sharpness, fat burning, and heart rate. Even the suppleness and strength of the skin, hair, and fingernails are significantly affected by thyroid function. All of these metabolic processes require fuel, making the thyroid a particularly “hungry” part of the body with respect to nutritional demands. When the thyroid is deprived, or “starved” of certain nutrients, however, the risk of subclinical hypothyroidism, frank hypothyroidism, and even Hashimoto’s disease (the autoimmune form of hypothyroidism) increase.
Thankfully, we can show our thyroid some love by eating a balanced diet and focusing on the nutritional factors that support the function of this very important gland.
Iodine deficiency has long been known to cause thyroid issues, with the most dramatic effect noted in babies born to iodine-deficient mothers. In fact, iodine deficiency is among the most prevalent (and preventable) causes of mental impairment to this day, worldwide.
Although congenital hypothyroidism (once troublingly known as “cretinism”) is rare in the developed world, the World Health Organization (WHO) nevertheless estimates that over 30% of the world’s population – some two billion people – have insufficient iodine intake. Even when congenital hypothyroidism is avoided, sub-optimal iodine levels may still limit a child’s cognitive development: even moderate iodine deficiency in a mother can lower her baby’s intelligence quotient (IQ) up to 16 points., For this reason, much attention is given in particular to pregnant and lactating women with regard to iodine intake.
Even moderate iodine deficiency in a mother can lower her baby’s intelligence quotient (IQ) up to 16 points.
Pregnancy and childbirth aside, iodine plays an integral role not only in ensuring adequate thyroid hormone production, but also in preserving the architectural integrity of the gland. Specifically, iodine deficiency may over time cause an enlargement of the thyroid gland in a condition known as goiter. In fact, areas of the United States with iodine-deficient soil were once known as the “goiter belt” prior to the introduction of iodized salt to the U.S. market in the 1920’s.,
As we become more aware of the negative health consequences of the sodium replete in table salt (such as its potential to elevate blood pressure), more and more health-conscious consumers are opting for mineral-rich sea salt, Himalayan salt, and other alternative products. As salubrious as these salt preparations may be, they are seldom enriched with iodine, which may leave health food shoppers at increased risk of iodine deficiency. Consuming sea vegetables like kelp and kombu is one natural way to increase iodine levels. Taking iodine supplements may also be of benefit – but beware: iodine excess can also cause harm to the thyroid.
The thyroid contains more selenium by weight than any other organ in the body. Selenium protects the thyroid from oxidative damage by supporting the production of glutathione peroxidase, a potent antioxidant enzyme., Without this protective enzyme, the thyroid gland is much more susceptible to damage from iodine and other agents., It’s for this reason that those living in regions with poor selenium soil content are more likely to develop Hashimoto’s (autoimmune hypothyroidism) and that selenium supplementation has been shown to decrease both thyroglobulin (TG) and thyroid peroxidase (TPO) autoimmune antibodies.,
The thyroid contains more selenium by weight than any other organ in the body.
Selenium is necessary not only for the health of the thyroid gland itself, but also for the proper activation of thyroid hormone: the enzymes that convert T4 (the less active form of thyroid hormone) to T3 (the bio-active version) rely on selenium. In other words: there would be no activation of thyroid hormone without selenium. It’s no surprise then that a lower ratio of T3 to T4 has been noted in those with low selenium status.
There would be no activation of thyroid hormone without selenium.
Whereas a Brazil nut grown in selenium-rich soil contains roughly 100 mcg of selenium, one grown in selenium-poor soil may contain only one-tenth that amount. Given the unreliability of the soil content of selenium from region to region, taking a selenium supplement may be a simple, reliable way to support the thyroid.
Zinc not only contributes to the proper production of thyroid hormones, but, like selenium, increases the body’s conversion of T4 (the inactive form of thyroid hormone) to T3 (the bio-active form). Zinc also improves cellular sensitivity to that T3. This means that zinc works not only at the level of the thyroid itself, but also in other areas of the body.
Zinc supplementation has been shown to normalize thyroid-stimulating hormone (TSH) levels, support serum T3 and total T3 levels, and decrease levels of reverse T3 (or rT3, the inactive form of the hormone). In a study done on rats consuming a zinc-deficient diet, zinc deficiency was correlated with reduced production of T3.
As with iodine, excess zinc supplementation may suppress thyroid function. Zinc also has an inverse relationship with copper, wherein zinc supplementation may interfere with copper absorption. For this reason, it may be advisable to also take copper when supplementing with zinc in high doses or for long periods of time.
The production of thyroid hormone relies upon the iron-dependent enzyme thyroid peroxidase (TPO). Iron deficiency thus causes a reduction in the synthesis of thyroid hormones, in turn increasing TSH levels and enlarging the thyroid. Iron repletion, on the other hand, has been shown to improve thyroid function in individuals with deficiency. Eating iron-rich foods like red meat and liver are therefore also likely to support thyroid health.,
The thyroid gland makes hormone by combining the amino acid tyrosine and iodine. Supplementation with L-tyrosine may therefore provide the body with more of the building blocks it requires for thyroid health.
Vitamin A deficiency may disrupt signaling from the brain to the thyroid, and has also been shown to hinder the thyroid gland’s uptake of iodine, thereby limiting its ability to synthesize thyroid hormone. Supplementation with vitamin A, however, has been shown in a study of premenopausal women to lower TSH levels and increase serum T3. Vitamin A supplementation can also mitigate the effects of iodine deficiency on the thyroid gland, thus reducing the risk of goiter. It’s also been said to improve the sensitivity of the cells of the body to thyroid hormone, like zinc.
Vitamin A supplementation can mitigate the effects of iodine deficiency on the thyroid gland, thus reducing the risk of goiter.
Hypothyroid patients tend to be deficient in B vitamins, but the exact reason for this is not yet clear. One explanation, however, may be that the slowing of metabolism seen in hypothyroidism compromises the digestive system’s ability to absorb dietary nutrients like the B12 abundantly found in red meat. The neurological problems that can result from B12 deficiency in particular make B vitamin supplementation warranted in those with thyroid problems. The B vitamins also support adrenal health, in turn enhancing thyroid function.
Vitamin D deficiency may increase the risk of Hashimoto’s, as those with lower vitamin D levels are more likely to have elevated thyroid autoantibodies., Vitamin D deficiency is also more common among those with thyroid nodules or thyroid cancer. It’s worth noting that beyond its important immunomodulation action and effects on mental health, vitamin D also acts like a hormone in the body, making it relevant in the care of endocrine ailments.
Those with lower vitamin D levels are more likely to have elevated thyroid autoantibodies.
Although it’s not a nutrient, the Ayurvedic herb ashwagandha – revered for its ability to help us better cope with stress – also deserves mention here.
In a 2018 randomized, double blind, placebo-controlled pilot study of 50 patients with hypothyroidism, 600 mg of ashwagandha root extract taken daily for 8 weeks was shown to improve serum TSH, T3, and T4 levels significantly as compared to placebo. These findings echo those of a rodent study, in which ashwagandha root extract raised serum T3 and T4 levels by 18% and 111%, respectively.
With all the hard work the thyroid does to support our health and wellbeing, it’s surely worth taking the care to feed it the nutrients it needs to continue doing its important job. Whether from food or from supplements, the thyroid is hungry for nutrition.
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