There are usually four small parathyroid glands at the back of the thyroid, close to the two vocal cord nerves. Despite its small size, the thyroid is extremely important as it produces and stores important hormones, which are secreted into the bloodstream when they are needed. These hormones are responsible for activating many important processes in your body, which prepare you for action – how well the thyroid works therefore has a major impact on your level of energy and feeling of well-being.
Thyroid hormones and their important tasks
- Influence on heart activity and blood pressure
- Energy regulation
- Conversion of carbohydrates which is important for healthy levels of insulin
- Lowering of cholesterol levels
- Influence on muscle strength
- Regulation of minerals which affect bone health
The two most important thyroid hormones are T3 (tri-iodothyronine) and T4 (thyroxine or tetraiodothyronine). The thyroid needs iodine to produce these hormones, which it obtains from the blood. The thyroid hormones are stored and secreted as needed into the bloodstream, which then transports them to the relevant organs. These hormones affect many body systems including the circulatory system, lipid changes, sweat glands and kidney and gut activity. In addition, T3 and T4 are mostly responsible for growth processes and energy consumption.