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Slow metabolism may be a result of not getting enough vitamin D and selenium

Slow metabolism may be a result of not getting enough vitamin D and seleniumA substantial number of people suffer from Hashimoto’s disease, a condition that causes hypothyroidism (slow metabolism), extreme fatigue, cold sensitivity, weight gain, and numerous other symptoms because the cells lack energy. Quite a few people suffering from this disease receive treatment, but the results are often unsatisfactory, and most people have not been given the correct diagnosis or do not receive proper help.

A new study shows that vitamin D supplements may ameliorate the disease by reducing those antibodies that attack the thyroid gland. Earlier research shows that selenium supplements also have an effect. However, even if you eat a healthy diet it may be difficult to get enough of these two nutrients. Moreover, with supplements it is vital that they are of such quality that the body can absorb and utilize them properly.

Hashimoto’s disease is often insidious and is the most common cause of hypothyroidism (slow metabolism). It belongs to the group of autoimmune diseases where the immune system erroneously attacks the body’s own tissues, causing chronic inflammation.
The antibodies involved in Hashimoto’s disease are called anti-TPO and attack the thyroid gland’s hormone-producing cells. Anti-TPO can be measured with a blood test.
As the thyroid gland is gradually attacked by anti-TPO, its production of the thyroid hormones T3 and T4 decrease. The low level of thyroid hormones often results in an increasing number of symptoms, depending on which tissues are affected by the energy shortage. To make matters worse, medical therapy with thyroid hormones often fails to deliver the expected results. Despite “normal” blood tests, up to 20 percent of patients feel increasingly worse.

Did you know that thyroid hormones help oxygen into the cells to help them convert (burn) nutrients and make energy?

Extra vitamin D gives new hope for patients with Hashimoto’s disease

It is already known that low vitamin D levels in the blood are associated with autoimmune diseases such as Hashimoto’s. The new evidence-based study was carried out on 34 female Hashimoto’s patients. All participants had been in medical therapy with Levothyroxine (a synthetic T4 hormone) for at least six months. According to American guidelines, the women had normal blood levels of vitamin D (over 30 ng/ml). Still, the researchers questioned whether the threshold levels are too low, and they wanted to know if vitamin D supplements are likely to make a difference.
The women were divided in two groups. One group got 50 micrograms of vitamin D daily for six months, while the other group got matching placebo during the same period. At the beginning of the study and after it was terminated, the researchers took blood samples to measure the women’s levels of pituitary hormone TSH (thyrotropin), T4 (thyroxine), free T3 (triiodothyronine), and vitamin D. They also measured levels of anti-TPO.
It turned out that those women who had taken vitamin D had elevated levels of vitamin D in their blood, but their levels of anti-TPO had gone down at the same time. Therefore, the researchers concluded that supplementing with 50 micrograms of vitamin D daily can reduce autoimmune reactions in women with Hashimoto’s disease, who are already receiving medical care and have normal vitamin D levels in their blood. The study is published in the journal Experimental and Clinical Endocrinology & Diabetes (April 2017)

Measuring vitamin D in the blood and various recommendations

Vitamin D in the blood is measured as 25-hydroxy-vitamin D. As mentioned earlier, the official American threshold levels for normal vitamin D levels are 30 ng/ml, while they are 50 ng/ml in Denmark. Leading scientist claim that even this is insufficient and suggest levels as high as 75-100 ng/ml as a way of obtaining optimal protection against disease. There is evidence suggesting that such levels work with autoimmune diseases like Hashimoto’s.

How much vitamin D do we really need?

The female Hashimoto’s patients received 50 micrograms of vitamin D daily, but many scientists believe that the actual need for vitamin D lies somewhere in the range of 30-100 micrograms. It is no problem to synthesize 30-100 micrograms of vitamin D on a nice and warm summer day, but during the winter, most of us need supplements, especially because the amount of vitamin D we get from our diet is minimal. Because vitamin D is lipid-soluble, the best way to take it is in some kind of oil in capsules, as this increases the absorption of the nutrient.

Upper safe limit and overdosing

The upper safe limit for daily intake of vitamin D as established by the European Food Safety Authority (EFSA) is currently 100 micrograms for older children and adults, including pregnant and lactating women.

Danish study to clarify selenium’s effect on metabolic disorders

Researchers from Rigshospitalet, Bispebjerg Hospital, Odense Universitshospital, and Sydvestjysk Sygehus (Esbjerg) are currently conducting two large studies of selenium’s effect on Hashimoto’s disease and Graves’ disease (that speeds up the metabolism). Both metabolic diseases involve autoimmune inflammation of the thyroid gland, and in both studies, which have similar designs, patients will receive 200 micrograms of selenium yeast or placebo together with their regular medication for a period of 12 months.
Blood samples will be taken at baseline and in the course of the study period to measure levels of thyroid hormones, T3 and T4, and antibodies. The patients’ quality of life will be assessed by means of a special questionnaire, which the scientists have designed for patients with metabolic disorders. The question is, what effects does selenium have on metabolism and on the inflammation, which is characteristic of all autoimmune conditions?

Selenium regulates the thyroid hormones

The thyroid gland produces two different types of thyroid hormone. T4 is the passive hormone that contains four iodine atoms, while T3 is the active hormone that contains three iodine atoms. In order to activate the metabolism in the different cells and tissues, special selenium-containing enzymes (deiodinase) remove one iodine atom from T4 and convert it into active T3

Why does hormone therapy not work?

Hypothyroidism is normally treated by administering a synthetic T4 hormone (Eltroxin, Euthyrox and Levothyroxine). A selenium deficiency could account for the lack of effect with this type of therapy, because the successful conversion of passive T4 hormone into active T3 depends on the selenium-containing enzymes.

Selenium is a powerful antioxidant that counteracts inflammation

Around five liters of blood per hour flush through the thyroid gland, which means that this gland is exposed to a large amount of free radicals. Stress, infections, tobacco smoke, alcohol, medicine, and mercury also generate free radicals, which may cause cellular damage and inflammation. A type of selenium-containing proteins (selenoproteins) called GPX work as powerful antioxidants that protect the thyroid gland against free radical damage and inflammation, provided we get enough selenium.

Did you know that the thyroid gland has the highest relative concentration of selenium?

We get less selenium from the diet, but we can compensate for this

The average selenium intake in Europe is lower than it is in other countries due to the selenium concentration in agricultural soil and dietary habits. However, by taking a daily selenium supplement in the range of 100-200 micrograms, it is possible to get the same amount of selenium as people do in countries like Canada, the United States, and Japan. The best way to get the same variety of different selenium compounds (like one gets from eating a balanced diet) is by taking organic selenium yeast.

Will selenium and vitamin D be the new standard treatment?

Numerous international studies have shown that supplements with organic selenium yeast have a positive effect on metabolic diseases such as Hashimoto’s disease and Graves’ disease. If the results from the two ongoing Danish trials with selenium yeast turn out to have a positive effect on metabolic disorders, supplementation with selenium yeast will be included as part of the standard therapy for these two diseases. Doctors will also check if there is reduced need for T4 (and Eltroxin), because selenium is able to increase levels of thyroid hormone and reduce levels of antibodies.
As for the recent vitamin D study, supplementing with larger doses of this nutrient may also be relevant, as it inhibits inflammation and lowers levels of antibodies.

Symptoms of hypothyroidism Symptoms of hyperthyroidism
(often precedes hypothyroidism)
Fatigue and poor concentration Fatigue and poor concentration
Cold sensitivity Feeling warm and sweaty
Slow pulse and perhaps tinnitus Fast pulse and palpitations
Weight gain despite reduced appetite Weight loss despite huge appetite
Swelling of throat/head Bulging eyes
Saggy, dry skin, hair loss, and jagged nails Trembling hands
Constipation Frequent and loose stools
Despair and a tendency to feel depressed Nervousness and other psychological symptoms
Irregular periods Irregular periods
Goiter (enlarged thyroid gland) Goiter (enlarged thyroid gland)
People rarely have all symptoms at once. Let your physician measure your metabolism if you suspect it is either too fast or too slow.


Krysiak R et al. The Effect of Vitamin D on Thyroid Autoimmunity in Levothyroxine-Treated Women with Hashimoto´s Thyroiditis and Normal Vitamin D status. Experimental and Clinical Endocrinology & Diabetes 2017

How to Reduce Thyroid Antibodies in Hashimoto’s: New Research 2017 – Sonia McNaughton

Tamer G. Relative vitamin D insufficiency in Hashimoto´s thyroiditis. Thyroid. 2011

The chronic autoimmune thyroiditis quantity of life serum trial (CATALYST): Study protocol for a randomized controlled trial

Selenium supplementation for patients with Graves’ hyperthyroidism (the GRASS trial): study protocol for a randomized controlled trial

Drutel, A et al: Selenium and the thyroid gland: more good news for clinicians. Clinical Endocrinology 2013

Gärtner R et al: Selenium supplementation in patients with autoimmune thyroiditis decreases thyroid peroxidase antibodies concentration. J Clin Endocrinol Metab. 2002

Shomburg, Lutz: Selenium, selenoproteins and the thyroid gland: interactions in health and disease. Nat. Rev. Endocrinol 8, 2012

EFSA (Den Europæiske Fødevaresikkerhedsautoritet)

Pernille Lund. Har du problemer med dit stofskifte? Ny Videnskab 2015

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