How does the thyroid gland work?
The thyroid consists of two so-called lobes that lie like a shield around the trachea under the larynx. The thyroid hormones that the thyroid produces are released into the blood, after which they are transported to all organs and tissues in the body. A healthy thyroid produces the right amount of hormones day and night and is also able to store hormones. It is mainly T4 that is secreted by the thyroid, T3 is the more active form that is largely only formed in the organs themselves. The hormones have a stimulating effect on the metabolism. For example, they encourage cells to use more energy, which makes the digestive system work harder and the body temperature rise. They also stimulate growth and development in the body, especially in nerve tissue, by stimulating body cells to produce proteins.
The thermostat of our body
The thyroid gland is controlled by two small organs in our brain: the hypothalamus and the pituitary gland. They have a function that is comparable to the thermostat in our living room. They monitor the blood and ensure that the thyroid gland produces more hormones if they notice that there are too few thyroid hormones in the blood. Conversely, they also ensure reduced production if there are too many hormones. With the help of iodine, the thyroid gland produces T3 and T4, also called thyroid hormones. Iodine enters our blood through food, after which it is actively absorbed by the thyroid gland. Furthermore, the thyroid gland also needs tyrosine, an amino acid that is found in almost all protein-rich foods.
What is an overactive or underactive thyroid?
Depending on our health and stage of life, there can sometimes be an overactive or underactive thyroid gland. For example, the production of thyroid hormones generally decreases as we get older. This delayed thyroid function is a natural phenomenon, resulting in a slower metabolism and increased body fat. When a woman is pregnant, there is often an overactive thyroid gland. The function of the thyroid gland is very important for the proper development of the fetus. During pregnancy, the thyroid gland is larger and the organ produces more hormones. After pregnancy, temporary changes can occur in the functioning of the thyroid gland. Sometimes there is more going on and there is an overactive or underactive thyroid gland. Medication can affect the functioning of the thyroid gland, but there may also be a condition such as hyperthyroidism (overactive thyroid gland) or hypothyroidism (underactive thyroid gland). For newborns and young children, who of course all go through enormous physical and mental growth, it is very important that the thyroid gland functions properly. In every newborn baby, the level of thyroid hormone in the blood is determined by means of a heel prick.
