Hormones are chemical messengers that travel throughout the body, controlling many of its functions. In particular, they influence growth and development as well as metabolism. Hormones can be found in both plants and animals; however, their mechanisms for action vary slightly between species.
In humans, hormones are produced by the endocrine system—a group of glands in the body which secrete hormones into the bloodstream. The pituitary gland, located at the base of the brain, is often referred to as the ‘master gland’ because it controls several other glands within the endocrine system. These include: thyroid gland; adrenal glands; pancreas; ovaries (in women); testes (in men); and pineal gland.
Each of these glands produce specific hormones, which travel through the bloodstream to their target organs or tissues. The hormones then bind to receptors on the cells, causing them to change in some way (e.g. increasing in size or activity). Examples of hormones include: testosterone; cortisol; insulin; oestrogen; progesterone; adrenaline; and thyroxine.
The levels of hormones can vary greatly between individuals and over time. They are also affected by age, lifestyle factors (such as stress), diet, exercise and even exposure to certain environmental toxins. It is important that hormone levels remain within a healthy range for optimal health and wellbeing.
By understanding how hormones work, it is possible to control their levels and help regulate the body’s functions. For example, medications such as birth control pills are used to adjust hormone levels in order to prevent pregnancy. Similarly, hormone replacement therapy can be used to replace hormones which may have become imbalanced due to a medical condition or age-related changes.
Overall, hormones play an important role in our bodies and it is essential that we understand how they work so that we can maintain our health and wellbeing.