The Anatomy of the Thyroid

The thyroid gland is a butterfly-shaped organ located in the neck, near the larynx. It is a small organ of only a few centimeters in size and about 25 grams, which produces thyroid hormones. It consists of two lobes that are made up of follicles. These hormones regulate activities in your body, such as growth, the functioning of the heart, metabolism, activities of body cells and other body processes. When the thyroid works too quickly or too slowly, this can lead to annoying symptoms.

Where the thyroid gland is located

Anatomy of the Thyroid and Parathyroid Glands

The thyroid gland, with the medical name thyroid , is a small organ in the form of a butterfly in the neck. It sits at the bottom of the neck, against the trachea and weighs about 25 grams in an adult. You can usually feel it when you feel your Adam’s apple while you are swallowing. It consists of a left and right part on both sides of the larynx, which is connected to a thin section. Usually the right part is larger than the left part. The two lobes of the thyroid are made up of follicles. C-cells lie between the follicles. It belongs to the endocrine organs, which means that it is an organ that secretes hormones.

Thyroid hormones

The follicles secrete the following hormones: thyroxine (T4) and triiodothyronine (T3). The intermediate C cells make the hormone calcitonin . The hormones are delivered to the blood so that it can be transported to all tissues in the body. The pituitary gland that is located within the brain produces the hormone TSHthat stimulates the thyroid gland. The thyroid gland mainly produces an inactive form of T4. This is converted into an active form of T3 in other tissues. At the moment when too many thyroid hormones are released in the body, the thyroid gland will produce less. This is also called negative feedback. The thyroid gland needs iodine to produce hormones. We get enough of this with a healthy diet.

Effect on the metabolism

In most places in the body, thyroid hormones increase the oxygen uptake and the production of heat. In the body cell are mitochondria, these are cell organelles that are involved in the formation of energy. For this they need sugars (carbohydrates). Due to the thyroid hormone, the mitochondria will increase in number and size. This will speed up the metabolism. The effects of a high metabolism are:

More sweating and better circulation of the skin
More need for oxygen, so you will breathe deeper and faster
Heart will beat faster
Higher blood pressure
Weight loss
Higher cholesterol levels

Normally the thyroid gland is well balanced due to the negative feedback of hormones, so that the metabolism is adapted to the body. At the moment that there are few hormones in the blood, the thyroid gland will produce more hormones.

What do thyroid hormones need?

The body needs these hormones for normal growth and development. They are important for the development of our bones, teeth, skin and the central nervous system. If children suffer from a too slow thyroid gland, this will lead to a delayed growth. Furthermore, thyroid hormones stimulate your alertness, reflexes, memory, learning ability and being awake.

Diseases of the thyroid gland

When a thyroid gland produces too much or too little thyroid hormone, it can lead to diseases. A thyroid gland that is too fast is called hyperthyroidism and a too slow thyroid hypothyroidism.

Hyperthyroidism (too fast thyroid gland)

A common condition is Graves’ disease. This is a disease in which antibodies turn against their own body (autoimmune disease), in this case against TSH. This leads to too much excretion of the thyroid hormone. The complaints are: increased metabolism, not heat, sweating, increased appetite, weight loss, insomnia, faster heartbeat, feeling nervous, muscle weakness, fatigue and being emotional.