An easy guide to understanding hormones
Hormones do more than just alter our moods. Hormones are fast-acting chemical messengers that circulate through the bloodstream communicating with different organs, forming the endocrine system. Hormones are produced selectively within major endocrine glands such as the pineal and pituitary glands in and near the brain, the thyroid and thymus glands in the upper chest and throat region, the adrenals and the pancreas near the kidneys, and the gonads (ovaries and testes in females and males, respectively). Hormones are carefully regulated in the body to keep us in balance.
The glands and their hormones have specific functions in the body. For example, the pituitary regulates growth as well the functioning of the other glands in the endocrine system. One interesting hormone it regulates is oxytocin, the hormone that causes the contraction of the uterus during pregnancy. Oxytocin is also known as the “love” hormone in science because it appears to regulate bonding in sexual partners and between the mother and infant. When oxytocin is not present, bonding either does not happen or is slower.
The adrenal glands participate, along with the pituitary, in the regulation of the stress response. They produce sex hormones and the well-known hormone epinephrine (a.k.a. adrenaline). These glands are activated every time we encounter a stressful event, so you can imagine how overused they could get when there is too much stress in our lives. In fact, because these glands are part of a loop that involves the pituitary and another region of the brain known as the hypothalamus, repeated stressful events can actually cause brain damage.
The gonads, in addition to producing sperm and eggs, also produce androgens (male sex hormones) and estrogens and progesterone (female sex hormones). They do many things including stimulate growth and development of sexual characteristics that allow us to appear male or female. In females, the estrogens and progesterone are also involved in conception and pregnancy.
Hormones have an important physiological influence in our body in terms of helping us grow and develop, respond to threats, stay balanced, and reproduce. It’s not surprising that problems can arise when synthetic or environmental chemicals mimic these natural human hormones.
Estrogen-mimicking compounds like Bisphenol A (BPA – synthetic estrogen found in some plastics) have earned popular press lately contributing to lower birthrates of males. A 2009 study by researchers Salian, Doshi, and Vanage was done to test this directly in rats. The found that when the moms were given BPA in their drinking water they had more “miscarriages” and the male offspring had both decreased sperm counts and sperm motility. Some of the effects they found were even present three generations later!
Estrogen-mimickers also exist naturally, for example from soy-based compounds called isoflavones; however, these compounds can have many positive effects like anti-carcinogencic (anti-cancer). In post-menopausal women they can reduce hot and decrease bone mineral density loss. However, there is some evidence that these compounds can increase the risk of breast cancer in estrogen-sensitive post-menopausal women. All of these effects are still currently being investigated because they appear to be dependent upon the specific isoflavones consumed and the quantities. So generalizing from these studies to each of us individual is difficult right now.
Not surprisingly, there is also research currently going on to understand the effects of the estrogens present in treated sewage as a result of women taking the birth control pill and post-menopausal women on hormone replacements. These hormones are not removed with the current sewage-treatment programs. The damaging effects of these levels are still not known.
The endocrine system is an important way that the body communicates with itself. And like any good communication system, anything that disrupts the flow of information can cause a whole host of problems. Scientists are working hard to better understand how hormone-disruptors are affecting us. In the meantime, it’s up to us to use our discretion about whether we want to ingest these estrogen-mimickers and to consult appropriate healthcare practitioners when necessary.
It’s also important to remember that our hormones are part of one whole system so if we affect one part of it, there are likely to be effects in other parts.
Hormone Health: You might want to read this article on hormone health as well!