Thyroid disease is a medical condition that affects the function of the thyroid. The thyroid gland is one of the largest glands in the endocrine system and is located in the neck. The thyroid cells absorb the iodine and convert it into two hormones; thyroxine (T4) and triiodothyronine (T3) which help control the body’s metabolism. The pituitary gland, which is located at the bottom os the brain, controls the thyroid gland. As the different levels of T3 and T4 become very low, the Thyroid Stimulating Hormone (TSH) is released from the pituitary gland to help increase the amount of T3 and T4 hormones. Once the levels of T3 and T4 are equal, the TSH will stop being produced.
There are two main types of thyroid diseases:
- Hyperthyroidism occurs when the thyroid gland produces and increased amount of T3 and T4 cells and usually leads to Graves diseases. This is an autoimmune disease in which the body produces thyroid antibodies that activate the production of the TSH.
- Hypothyroidism occurs when the thyroid gland doesn’t produce enough hormones and usually results in Hashimoto's thyroiditis. This is another autoimmune disease in which the thyroid gland becomes swollen due to body’s own cells attacking the thyroid.