The Important Role of Vitamin D in Graves’ Disease
Graves’ disease is an autoimmune disease of the thyroid gland, which was described by the Irish physician Robert James Graves in 1835. It was first recognized in the 19th century as a syndrome involving an overactive thyroid gland, manifested by goiter, palpitations and various types of eye pathological conditions. Many characteristic signs and symptoms of Graves’ disease result from high levels of thyroid hormones. It is diagnosed by low levels of thyroid stimulating hormone (TSH) and high levels of free thyroxine (FT4).
Graves’ disease occurs as a result of complex interactions between genetic and environmental factors and it is a more severe form of autoimmune thyroid disease than Hashimoto’s autoimmune thyroiditis, mainly due to the adverse effects of high thyroid hormones on vital functions, which may endanger the patient’s life.
Vitamin D and Graves’ Disease
It is widely known that the most important role of Vitamin D is to maintain the homeostasis of calcium and phosphorus to enhance bone health. However, its beneficial effect is not limited to this. Adequate reserves of Vitamin D in the body strengthen its defenses and consequently prevent or limit the development of autoimmune diseases, which are associated with thyroid dysfunction.
Recent evidence suggests that Vitamin D may play a vital role in endocrine disorders, particularly type 1 and 2 diabetes and polycystic ovary syndrome. This is because Vitamin D greatly contributes to the body’s immunity. In recent years, it has been claimed that it strengthens the cells of the immune system and consequently has anti-inflammatory function.
In particular, Vitamin D has been shown to inhibit the stimulation of T and B lymphocytes. In particular, it reduces the production of cytokines, such as interleukin IL -12 and IL-23.
Therefore, when Vitamin D is within normal levels, the risk of developing autoimmune thyroid diseases, such as Graves’ disease, can be prevented or reduced. So, according to recent scientific data, it seems that Vitamin D deficiency, especially when levels are less than 12.5ng / ml, should be considered a very important risk factor for the development of autoimmune thyroid disease.
How important is Vitamin D after all?
Very recent scientific findings show today that Western Europe, and of course Greece, is facing a “pandemic” of Vitamin D deficiency. Although Vitamin D is synthesized through the effects of sunlight on the skin, some genetic factors interfere with its proper synthesis. An inhibitory factor, for example, is the widespread use of sunscreen, as it blocks the action of sunlight on our skin. Thus, the human body is deficient in Vitamin D.
Given that 80% of Vitamin D is synthesized by the sun, while only 20% is absorbed through the diet, eating foods rich in Vitamin D is not the only way to boost its levels in the human body. However, we need to know that foods rich in omega fatty acids have high Vitamin D stores. So, it is contained in large quantities in fatty fish, but also in some fruit.
It is recommended to measure the levels of Vitamin D in almost every age group and the timely intervention with its supplementary administration, where there is necessity, because its adequate values in the human body help prevent the development of autoimmune diseases. It is also of the outmost importance to focus the attention of physicians on understanding the pathophysiology of Graves’ disease, on its early diagnosis, on treatment strategies and on the prevention of recurrence of the disease, in order to achieve optimal and integrated management of patients with Graves’ disease.
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