How Hormones Work

Shifts in hormone balance take place throughout our lives; adolescence and menopause or andropause are prime examples. But some shifts may signal or reflect health issues that can range in severity from merely uncomfortable, to actually troublesome, or even truly devastating. If hormonal changes make it difficult to live your best life, find your healthy balance...understanding how hormones interact is the foundation.

The larger hormone groups listed below can play major roles in basic hormone balance, and are vital to living your best life. 

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The Estrogens
The hormone that is fundamental to the female of the species is actually a family of three: estradiol, the most active form of estrogen; estrone, the inactive storage form of estrogen; and estriol, the weaker of the estrogens.

Estrogen has been labeled “the angel of life,” because it makes cells grow, developing the uterus, breasts, periods, pregnancy and the egg within the ovary—and “the angel of death,” because in excess it becomes toxic to the body. As they say, too much of a good thing can be dangerous, and too much of an estrogen that causes cells to multiply out of control is a recipe for breast cancer. Determining symptoms of estrogen dominance is a smart move since an imbalance of high estrogen to low progesterone that goes undetected for too long is not a risk worth taking.

Progesterone: the Estrogen Balancer
Progesterone is the sister hormone to estrogen, working in tandem with it to regulate and protect the health of the reproductive system throughout our fertile years. Among its many vital functions, progesterone governs the second half of the menstrual cycle and is essential to maintaining a pregnancy to term. It also plays a part in the regulation of blood sugar levels, has inherent calming properties, and protects breast, brain and bone health. When it comes to breast cancer prevention, progesterone’s most important role in the body is to balance estrogen.

Like its teammate, estrogen, progesterone is primarily made in the ovaries but unlike estrogen it can only be produced at ovulation. The ruptured follicle that releases an egg upon ovulation then pumps out progesterone for the rest of the cycle. So if and when we don’t ovulate, our bodies do not produce enough progesterone to keep estrogen levels in check—and that sets us up for estrogen dominance. In a nutshell: progesterone deficiency = estrogen dominance = heightened risk for weight gain, water retention, PMS, mood swings, endometriosis, fibroids, fibrocystic breasts and breast cancer.

Lack of ovulation, whether it occurs naturally as the result of aging ovaries, or unnaturally, from extremes of stress, exercise, diet, and/or use of synthetic hormones in HRT or birth control pills, will cause estrogen to drop from 40 to 60 percent (enough to stop the menstrual cycle), but progesterone levels plummet much lower, to nearly zero in some women causing a raft of symptoms from heavy/painful periods, mood swings, PMS and depression to water retention, weight gain, slowed thyroid function, and heightened risks for endometriosis, fibroids, fibrocystic breasts as well as breast and uterine cancer. It all boils down to the right ratios: in the landmark British study (Mohr, PE; Br J Cancer 1996) researchers found that women with breast cancer whose progesterone level at the time of surgery was above the adequate level, had significantly improved chances of survival.

Estrogen and Progesterone: Hormones in Balance

Estrogen and progesterone are finely balanced and are said to “oppose” one another by performing opposite functions, but in so doing, they balance or mediate each other. The following chart clarifies the counterbalancing effects of progesterone upon excess estrogens:


As the chart above clearly illustrates, estrogen and progesterone are fundamental balancing partners at every stage of a woman’s lifecycle. At midlife, supplementing a balanced cocktail of both relieves symptoms, improves weight loss, moods, energy, and protects against breast cancer.

Testosterone, DHEA and Hormone Balance
Testosterone is an androgenic hormone, or “androgen” (from the Greek, “andro” for male), so named because it is most commonly associated with the development of male characteristics.  Although testosterone is present in much smaller amounts in women than in men, it has a wide range of essential functions for a woman’s health. These include maintaining libido and sexual function, as well as the normal growth and renewal of muscles, bone and other tissues. It may also have a role to play in protecting breast health at a cellular level.

Levels of testosterone and its precursor, DHEA, decrease in women at menopause, and are often particularly low in women who have a “surgical menopause” or total hysterectomy with removal of the ovaries.  This is when symptoms of “androgen deficiency” can start to become apparent.  Along with the most noticeable effect of lowering libido, low testosterone and DHEA can also result in depression as well as a decrease in bone density, and lean muscle mass accompanied by a drop in metabolism and rise in body fat.

Sometimes, however, mid-life women can develop “androgen dominance” as testosterone levels can become high relative to declining ovarian estrogen and progesterone production. Drs. John Lee and David Zava, in their book What Your Doctor May Not Tell You About Breast Cancer, speculate that elevated levels of testosterone in women may be the result of the hormonal imbalance caused by menopausal estrogen dominance and the lack of progesterone.

Cortisol, The Master Stress Hormone
In healthy individuals, normal levels of cortisol—the adrenal hormone that maintains the immune system and manages our stress-coping response 24 hours a day—should be highest in the morning when we need to “get up and get going,” and decrease steadily to its lowest point at night, when we need to sleep. But the stress-coping demands of 21st century living can wreak havoc on this normal circadian rhythm, disrupting our ability to sleep through the night, focus on our work, and take life’s daily challenges in stride. When cortisol levels are out of balance, we tend to feel “tired and wired” all the time and/or may suffer from asthma and allergies, chemical and noise sensitivities, anxiety, eating disorders and stubborn belly fat. We may find ourselves crashing in the afternoon, craving sugar and caffeine to cope, and catching every cold and flu bug that comes along. The bottom line is adrenal exhaustion: when the body can no longer keep up with the demand for constant cortisol we hit bottom and may find ourselves at serious risk for chronic illness and autoimmune disease, premature aging, and breast cancer.

Metabolism and Thyroid Hormone Balance
The Colorado Thyroid Disease Prevalence Study in 2000 found the rate of hypothyroidism in the general population to be approximately 10%, with an estimated 13 million undiagnosed cases of low thyroid among American adults. Interestingly, women have an approximately seven times greater risk for developing thyroid problems than do men. Thyroid hormone regulates metabolic rate, so low levels tend to cause unwanted weight gain, depression, low energy and cold intolerance. High thyroid levels (hyperthyroidism) cause “hyper” energy levels, a feeling of being too warm all the time, and persistent weight loss. But it is hypothyroidism, or low thyroid, that is most common in women during the perimenopausal and postmenopausal years; in fact, some 26% of women in or near menopause are diagnosed with hypothyroidism. Coincidentally this is also the time when ovulation and ovarian hormone production wanes and eventually ceases, leading to a dramatic reduction of progesterone. This deficiency leads to estrogen dominance, the hormonal imbalance most strongly associated with low thyroid symptoms and the development of hypothyroidism.

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