The thyroid gland is the starting point for various diseases, which have different causes and can influence our entire body.
The thyroid gland is located in the neck, below the larynx. It is a small organ, usually not heavier than 25 g, and looks like a butterfly. It is an important metabolic organ because it controls the overall metabolism and thus influences the basal metabolic rate, i.e. all chemical processes in the body that are required to produce energy. The basal metabolic rate is responsible for energy utilization in the body. An example of that is a person who has clear weight problems and can lose weight with great difficulty even though he or she has a disciplined healthy diet and does sports. Another example would be a person can eat what he or she wants but does not gain weight, he or she remains slim and has more problems gaining weight. The task of the thyroid gland is the production and release of the two thyroid hormones T3 (triiodothyronine) and T4 (tetraiodothyronine or thyroxine).
These hormones decisively determine the metabolism of the organism and influence numerous bodily functions. These include energy consumption, the regulation of body heat, the activity of nerves, muscles, heart, circulation, stomach and intestines, mental well-being, sexuality and, especially in children, physical and mental development.
The most common thyroid diseases are:
- Hypothyroidism (underactive thyroid)
- Hyperthyroidism (overactive thyroid)
- Goiter (Struma)
- Hashimoto (chronic inflammation of the thyroid gland)
- Graves’ disease (autoimmune thyroid disease)
Hypothyroidism (underactive thyroid)
A hypothyroidism results from a long-term reduction in the production of thyroid hormones. The deficiency of these hormones can be caused by reduced stimulation by the pituitary gland, defective hormone synthesis or impaired cellular conversion from the thyroid hormones T3 to T4. Hypothyroidism is usually recognised by symptoms such as depressive moods, listlessness, signs of fatigue and cold hands and feet.
Iodine is considered to be one of the most important micronutrients that should be supplemented during an adjunctive therapy of hypothyroidism. Iodine is a component of the two thyroid hormones T3 and T4 and thus ensures the normal function of the thyroid gland. According to current studies, zinc deficiency is also associated with hypothyroidism. Thus, the additional intake of zinc is also a big advantage.
Vitamin D deficiency can also play an essential role in the development of hypothyroidism. A study carried out in November 2013 found the connection between vitamin D deficiency and calcium deficiency, and the development and extent of hypothyroidism.
Iron is of great importance in the formation of thyroid hormones. Consequently, having an iron deficiency can impair the function of the thyroid gland. In this context, the stronger the iron deficiency, the more pronounced the negative effects appear to be on the thyroid gland, especially with regard to struma development and the formation of thyroid hormones. However, it is also true that the stronger the iodine deficiency, the more negative the effects of iron deficiency on the thyroid gland appear to be. Iron deficiency also affects the therapeutic success of iodine substitution. Several clinical intervention studies have shown that in children with goitre and simultaneous iron deficiency, combined iron/iodine supplementation affects thyroid gland size and thyroid hormone status more favourably than in children with exclusive iodine substitution.
Hyperthyroidism ( overactive thyroid)
Hyperthyroidism is caused in more than 95% of cases by Graves’ disease (autoimmune thyroid disease) or by functional autonomy, an uncontrolled production of thyroid hormones. Typical symptoms of hyperthyroidism are insomnia, nervousness, restlessness and increased appetite.
The body’s own L-carnitine level is reduced in cases of hyperthyroidism. Carnitine supports various functions in the thyroid hormone metabolism. Studies have shown that a supplementation of L-carnitine can reduce symptoms and possibly have a preventive effect.
In the case of hyperthyroidism, there is also a coenzyme Q10 plasma deficiency. According to the study, this deficit is attributed to the increased mitochondrial activity in hyperthyroidism, as more coenzyme Q10 is consumed by the acceleration of the mitochondrial respiratory chain. Due to the increased metabolic activity and the influence of the thyroid gland on the vitamin B2 concentration, increased oxidative and nitrosative stress, also known as nitrostress, as well as hyperhomocysteinemia can generally be present. For this reason, nutritional medical treatment should be considered.
Goiter (Struma)
Struma, also known as goitre, is an enlargement of the thyroid gland, usually related to a nodular remodelling of the tissue. Mostly the cause for a goitre is a dietary iodine deficiency that lasts for years. Due to certain growth factors, thyroid cells multiply and the organ expands.
The growth and size of an existing goiter is also influenced by the level of selenium. In people suffering from both iodine and selenium deficiency, the intake of iodine alone has no positive effect on the volume of the goiter. Selenium, on the other hand, can reduce the size of a goitre for the long term.
Hashimoto (chronic inflammation of the thyroid gland)
Hashimoto’s thyroiditis is the most common autoimmune thyroid disease and occurs when iodine levels are sufficiently high. A malfunctioning mechanism of the immune system leads to tissue destruction by T lymphocytes. This leads to chronic inflammation of the thyroid gland. In the early stages, the disease can manifest itself with hyperthyroidism symptoms such as cravings, nervousness and tachycardia. Later on, however, the symptoms of hypothyroidism are in the foreground. This can lead to lethargy, depressive moods and reduced body temperature.
Several studies have shown that selenium contributes to a significant reduction in anti-thyroid peroxidase (anti-TPO) antibodies. This reduction in antibody concentration can be demonstrated both after six months and after nine and twelve months, underlining the importance of long-term selenium intake. Irrespective of the reduction in antibodies, an improvement in patients’ well-being can also be achieved, possibly attributable to the direct effect of selenium on cerebral and cognitive functions.
Omega-3 fatty acids help form “good Eicosanoids” which act as local anti-inflammatory mediators. This is why the correct ratio of omega-3 to omega-6 fatty acids (1:5) is recommended. In this way, increased inflammation and thus progression of thyroiditis (inflammation of the thyroid gland) can be avoided.
Graves’ disease (autoimmune thyroid disease)
Graves’ disease is an autoimmune disease in which autoantibodies bind to the thyrotropin receptor (TSH). This leads to increased production of the thyroid hormones T3 and T4 and hyperthyroidism. Symptoms of this autoimmune disease are an enlarged thyroid gland (goiter) and the protrusion of the eyeballs (exophthalmos). In addition, there are the typical symptoms of hyperthyroidism.
As it is suspected that a predominant imbalance between oxidants or radicals and the antioxidative system is one of the causes of Graves’ disease, selenium also plays an important role in this condition due to its antioxidative properties. People suffering from Graves’ disease are usually diagnosed with a greatly reduced selenium level, which is why the patients benefit from an additional selenium intake. In addition, selenium supplementation supports the regression of the normal state of the thyroid gland. A reduced vitamin D level has also been found in several studies in people suffering from Graves’ disease.
