Hormones are chemicals that carry messages from glands to cells within tissues or organs in the body. They also maintain chemical levels in the bloodstream to help achieve homeostasis, which is a state of stability or balance within the body. There are two types of these chemicals, known as steroids and peptides. The word "hormone" comes from a Greek word that means "to spur on." This reflects how hormones act as catalysts for chemical changes at the cellular level that are necessary for growth, development and energy.
How They Work
As members of the endocrine system, glands manufacture hormones. These chemicals circulate freely in the bloodstream, waiting to be recognized by a target cell, which is their intended destination. The target cell has a receptor that can be activated only by a specific type of hormone, after which the cell knows to start a certain function within its walls. Genes might get activated, for example, or energy production resumed. An autocrine hormone acts on the cells of the secreting gland, and a paracrine hormone acts on nearby — but unrelated — cells.
In general, steroids are sex hormones that are related to sexual maturation and fertility. Steroids are made from cholesterol, either by the placenta when the body is still inside the mother's womb or by the body's adrenal gland or gonads — the testes or ovaries — after birth.
Cortisol, an example of a steroid hormone, breaks down damaged tissue so that it can be replaced. Steroids determine physical development and fertility cycles from puberty through old age. If a person's body is not synthesizing the correct steroidal hormones, he or she can sometimes supplement them pharmaceutically, as with estrogen and progesterone.
Peptides regulate other functions, such as sleep and blood sugar concentration. They are made from long strings of amino acids, so they sometimes they are referred to as protein hormones. Human growth hormone, for example, helps the body burn fat and build muscles. Another peptide hormone, insulin, starts the process to convert sugar into cellular energy.
Hormones so perfectly and efficiently manage homeostasis because of negative feedback cycles. The body's goal is to keep the concentration of a certain chemical, such as testosterone, at a constant level for a certain period of time, similar to how a thermostat works. Using negative feedback, a change in conditions causes a response that returns the conditions to their original state. For example, when a room's temperature drops, the thermostat responds by turning on the heat. The room then returns to the ideal temperature, and the heater turns off, keeping the conditions relatively constant.
What are the Different Types of Hormone Therapy Drugs?
Hormones play an important role in health and are especially significant when a woman reaches menopause. The female body produces fewer hormones after the onset of menopause, and hormone therapy drugs are used to combat this natural reduction in hormone levels. Common hormone therapy drugs include estrogen and progestin. Natural hormone therapy can include black cohosh, dong quai root, ginseng, kava, red clover and soy.
Estrogen and progesterone are the two most prominent female hormones, and both diminish with age. Typical replacement medications for these hormones are estrogen and progestin, which is a synthetic form of progesterone. Hormone therapy drugs are used to treat the symptoms of menopause, which can be severe and disabling for some women. Common menopausal symptoms include hot flashes, night sweats, sleep disruption, vaginal dryness or itching, mood swings, depression and decreased libido.
While hormone levels do get a boost from estrogen and progestin treatments, some research has shown that hormone replacement drugs may increase the risk for cancer. The cancer claims are sometimes disputed, because studies indicate that hormone therapy drugs can cause certain types of cancer and prevent others. The risks that may accompany hormone replacement therapy are personal and should be discussed with a health care professional.
Natural menopause treatments have grown in popularity as an alternative that may not carry the risks associated with hormone therapy drugs. Although natural hormone replacement therapy is not as thoroughly researched as drug therapy, studies have shown that black cohosh root may reduce the occurrence and severity of hot flashes and night sweats. Research also found that ginseng and kava might alleviate some of the emotional symptoms of menopause and provide a feeling of overall wellness.
Phytoestrogens, which are plant-based forms of estrogen, are also used as a natural hormone treatment. Soy-based phytoestrogens, flax seed and flax seed oil can be used to treat hot flashes. Another phytoestrogen called coumestan is taken for bone loss caused by osteoporosis, which sometimes accompanies menopause. As with any medicine, natural hormone therapy drugs may have side effects and should be used with care.
Hormone replacement drugs usually come in pill form and are taken once every day. Other forms of hormone therapy include medicated creams and the transdermal patch. Menopause treatment creams containing estrogen and progestin can be applied to the abdomen, breasts, inner arms, inner thighs or vaginal area. The patch is placed directly on the skin and administers the treatment slowly through absorption.