What Is TSH?
TSH stands for thyroid-stimulating hormone. It is a hormone released by the pituitary gland, which is located on the base of the brain. This substance works as a messenger for the thyroid gland and helps control the amount of thyroid hormone produced, including calcitonin, thyroxine, and triiodothyronine. When the pituitary gland releases more TSH, the thyroid will release more hormones that control growth and metabolism. [1]
Normal TSH Levels
The normal levels of TSH can vary, depending on whether you are pregnant and your age. Older people tend to have higher ranges. Gender can also play a role. In general, the normal range of TSH in healthy individuals is from 0.4 to 4 mU/l. When the levels are lower than 0.4 mU/l, it causes hyperthyroidism. When the levels are higher than 4, it causes hypothyroidism. Most health providers use those reference values. Nevertheless, there are still a lot of controversial and other ranges. [2]