The endocrine system regulates the body's major continuous and prolonged processes including reproduction; growth and development; cellular metabolism and energy; blood balance of nutrients, electrolytes and water; and the immobilization of body defenses against stressors (things that cause wear and tear on the body's physical and mental resources). It is made up of eight different glands located strategically throughout the body: the ovaries (In men, the testes), adrenals, pancreatic Islets, thyroid, parathyrold, pineal, pituitary and the hypothalamus, which Is also part of the nervous system. Besides these major organs, the system Includes pockets of hormone-producing cells In tissues in the small Intestine, heart, kidneys and stomach. The endocrine system develops and begins producing hormones by the end of the second trimester of fetal.
In the order of endocrine command, the hypothalamus is the body's CEO, orchestrating the events of the rest of the endocrine system. The hypothalamus controls autonomic reflexes (such as the activity of the heart and smooth muscles), and it houses the body's "thermostat" and biological clock, which maintains the body's rhythm of 24 hour sleep-wake cycles. The somewhat mysterious pineal gland also has a role in biological timekeeping being an organ sensitive to retinal response to light. The pineal gland1 believed to coordinate fertility hormones, produces melatonin, the hormone known for Its sleep-triggering ability.
The hypothalamus also initiates part of the adrenal stress response, causing the pituitary to secrete the hormone that travels to the adrenal glands to stimulate secretion of cortisol, DHEA and aldosterone. The hypothalamus also Initiates 'the female cycle by producing gonadtropin-releasing hormone (GnRH), which signals the pituitary to secrete foliici stimulating hormone (F$H). FSH stimulates the ovaries to secrete estrogen, the sex hormone that stimulates development of breast, uterine and ovarian tissue (and in synthetic HRT forms is associated with excessive cell growth that leads to cancer).
When estrogen reaches a certain level, It signals the hypothalamus to trigger the pituitary to secrete luteinizing hormone (LH). Estrogen levels then fall, while the level of LH rises and peaks (around day 14 of a 28day cycle), stimulating ovulation, the release of an egg from its ovarian follicle. After ovulation, the follicle (now called the corpus luteum) is filled with cholesterol, which is converted first to pregnenolone and then to progesterone. This newly made progesterone is used In part for the building up of the uterine lining. If after about 13 to15 days the egg Is not fertilized, the uterine lining is sloughed off (in menstruation) when both estrogen and progesterone levels drop
Both estrogen and progesterone are necessary in the female cycle, and their balance is key for full health. Many women in our culture have an imbalance of these hormones, especially, insufficient levels of progesterone to counter excessive estrogen - an imbalance further exacerbated by chronic stress. Progesterone is a hormone important to a number of body functions. During times of stress or conditions of chronic adrenal hyper-stimulation, progesterone is capable of being converted into the stress hormone cortisol.
When one goes through chronic or severe long-term stress, the hypothalamus at first triggers an overproduction of the adrenal hormones (especially cortisol and DHEA). This eventually leads to adrenal insufficiency, a state in which the exhausted adrenals cannot respond adequately.
The thyroid gland Is also adversely affected by chronic stress. This gland's roles include regulating calcium metabolism and glycolysis, the breakdown of glucose for body energy fuel. Under normal conditions, the fight-or-flight response causes the thyroid to increase glucose breakdown. In conditions of chronic stress, however, the thyroid is continually overstimulated and eventually becomes depleted. Thyroid function is also disrupted by excessive estrogen, but this can be prevented by adequate progesterone levels.
Hyperthyroidism (overactive thyroid functioning) and especially hypothyroidism (low functioning) have become more common. The classic symptoms of hypothyroidism Include sluggishness, early morning fatigue, cold extremities, lowered basal temperature and menstrual problems, Including scanty periods.
Adrenal and other hormonal gland dysfunctions can cause some of the above symptoms and more, Including cravings for sweets, weight gain, allergies, heart palpitations, insomnia, depression, fatigue, poor memory, foggy thinking, headaches, nervousness, Inability to concentrate, recurrent Infections and glucose intolerance.
One very damaging adrenal dysfunction is excessive cortisol production, which causes, among other serious problems, Increased calcium mobilization from the bones, leading to osteoporosis, or loss of bone density. in a person with a healthy stress response, excessive levels of cortisol are automatically buffered. Constant stress destroys this feedback loop.
Hormonal Imbalances compromise not only physical health but also psychological health, manifesting as problems ranging from depression to panic disorder. One way the body tries to compensate for Imbalances created and exacerbated by the demands of stress is to overproduce key hormones. Another way it tries to compensate is by converting sex hormones to stress hormones, thus further diminishing reproductive functions and the enjoyment of sexual health.
It is helpful to learn about these hormonal interdependencies because they allow one to see the bigger picture, that the problems commonly associated with menses or menopause are actually indicators of greater endocrine imbalance. For many women, the next step In understanding the bigger picture might be to look at digestive health - such as the possibility of malabsorption syndrome or food allergies-and at nutritional supplementation strategies that help restore or maintain hormonal balance.
