Low Vitamin D & TSH Levels

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TSH, or thyroid stimulating hormone, is produced by the pituitary gland. Its main function is to regulate the production of thyroid hormones thyroxine and triiodothyronine by the thyroid gland. The thyroid hormones play an important role in metabolism of lipids and carbohydrates, and in normal growth and development of children. Increased levels of TSH occur when the thyroid gland is unable to produce the required amount of thyroid hormones, while increased levels of thyroid hormones, or hyperthyroidism, may lead to low TSH levels. Certain vitamins, such as vitamin D, may play a role in regulating thyroid and TSH levels in the body.

About Vitamin D

Vitamin D is a fat-soluble vitamin that is essential for the absorption of calcium and maintenance of bone health. MedlinePlus recommends 400 to 800 IU of the vitamin per day, depending on the age and overall condition of the patient. Very few foods contain vitamin D. You can find this vitamin in fortified cereals and dairy, oysters and certain fatty fish. The human body can also produce significant amounts of the vitamin when exposed to sunlight. Your doctor may suggest taking vitamin D supplements to treat a variety of conditions including vitamin D deficiency, osteoporosis, arthritis and certain types of cancers.


Low levels of vitamin D in the blood are associated with increased concentration of the TSH, according to the results of a study presented at the 2011 European Congress of Endocrinology. This can, in turn, lead to abnormal thyroid hormone levels and thyroid disorders. A study published in the May 2011 issue of the "Cellular and Molecular Immunology" also reveals the low vitamin D levels increase the risk of autoimmune thyroid disorders during which the immune system mistakenly attacks its own thyroid hormones. This can also lead to abnormal TSH levels in the body. Additionally, the website Diabetes.co.uk also reported in June 2011 that new studies indicate that individuals with low vitamin D levels may have poor thyroid functioning.


Side Effects

Vitamin D is generally safe to use, although excess levels may lead to calcification of tissues, kidney stones, nausea, vomiting, constipation, loss of appetite and weight loss. It may also interfere with certain blood pressure and corticosteroid medications.


Vitamin D may not help all thyroid disorder patients. Hence, do not use them without consulting a doctor. Inform the doctor about your pre-existing conditions and any other medications you might be taking.