An Overview of the Three Most Commonly Known Sex Hormones That Affect Health: Estrogen, Testosterone and Progesterone
Hormones and nutrients work together to create balance in the body. One cannot exist without the other. Micronutrients regulate, synthesize and detoxify hormones. Like nutrients, hormones work in balance and affect each other profoundly. Following is a primer on basic hormones that affect our health:
Estrogen actually exists in three main forms, some of which are helpful and some of which are quite harmful. Considered the primary female sex hormone, estradiol (E2) is one of the three major circulating hormones known collectively as estrogens – estrone (E1) and estriol (E3) being the other two. Estradiol is by far the most active of the three estrogens. It is 10 times stronger than estrone and 80 times stronger than estriol, meaning it has a strong affinity for estrogen receptors in tissue around the body and thus exerts a potent biological and clinical effects. It is considered an end-point hormone in that estradiol generally acts directly on biological tissue and does not convert into other hormones, versus precursor hormones like progesterone or androstendione, which are used to make other hormones.
In women, estradiol is manufactured primarily in the ovaries before menopause and in the adrenal glands after menopause. In men, small amounts of E2 are produced in the testes. An enzyme called aromatase can also convert testosterone into estradiol in both men and women. Since this enzyme is found primarily in adipose tissue (fat cells), overweight women and men may have excess estradiol relative to other hormones like testosterone. In premenopausal women, estrogen levels fluctuate throughout the menstrual cycle peaking around ovulation.
Estrogens are considered heart protective because they increase good cholesterol (high density lipoprotein, or HDL), improve smooth muscle tone in blood vessels and promote vasodilation, which expands arteries to allow healthy blood flow throughout the circulatory system. Estradiol prevents bone loss, thus lowering risk of osteoporosis, and improves collagen formation which results in younger looking skin. Estradiol also prevents loss of cognitive function as we age and increases the immune response. However, estrogen also exerts a strong proliferative (overgrowth of tissue) effect on hormone sensitive tissue such as the breast, ovary and uterus. Excess estrogen, especially when progesterone is relatively low, can increase risk of breast, ovarian and uterine cancer as well as conditions associated with tissue proliferation that may not be cancerous such as uterine fibroids, fibrocystic breast disease, or breast tenderness that occurs during periods. In men, estrogen plays a role in maintaining healthy sperm.
Low levels of estrogen can cause thinning skin, vaginal dryness, urinary tract infections or brain fog. Excess estrogen manifests clinically as premenstrual related symptoms such as breast tenderness, endometriosis, weight gain, acne or depression or menopause related symptoms such as hot flashes and memory loss. When not balanced by appropriate levels of progesterone, normal levels of estrogen can manifest clinically as excess estrogen, and this condition is often referred to as estrogen dominance. Unopposed estrogens are exogenous estrogens that are not balanced (not opposed) with appropriate levels of progesterone, which selectively balances estrogen’s biological activity. High estrogen levels may also indicate a need to improve estrogen detoxification, which is critical to reducing breast cancer risk. High levels may also indicate insulin resistance since insulin causes the ovaries to decrease SHBG, which then allows more estrogens into circulation. Several nutrients affect both estrogen levels and estrogen metabolism.
is the most potent circulating sex steroid. Produced primarily in the testes in men and the ovaries in women, it is most often clinically associated with increased muscle mass, enhanced libido, bone health and a general sense of well being. Levels in healthy women are 5-10% of the levels found in healthy men. Testosterone that is bound to SHBG is biologically inactive.
Symptoms of excess testosterone in women are increased facial hair (hirsutism), acne and polycystic ovary syndrome, while excess testosterone in males often manifests behaviorally (aggressiveness, hyperlibidio, etc.) Symptoms of low testosterone in either sex include low libido, decreased muscle mass and depression.
Only free, unbound testosterone is biologically active. Since the amount of SHBG profoundly affects testosterone’s influence on the body, it should be evaluated in the context of other hormones. For example, testosterone can be aromatized (chemically changed) into estradiol. Similarly, luteinizing hormone and follicle stimulating hormone both regulate the production of testosterone.
Progesterone is a sex hormone that works primarily to balance the potent effects of estrogens in the body. Specifically, progesterone counteracts the proliferative (tissue growth) effects of estrogen on hormonally sensitive tissue, such as breast and uterus, and selectively balances the effects of estrogen on other tissues including the brain, bones and skin. Unopposed estrogen (also known as estrogen dominance) occurs when there is insufficient progesterone to counteract estrogen.
This hormone, which is very high during pregnancy, is responsible for keeping a fertilized egg viable, which is why low levels are often associated with infertility. While estrogen increases the immune response, progesterone depresses immunity, which is good because otherwise a woman would expel a fertilized egg as a foreign invader. In a premenopausal woman, large amounts of progesterone are released in the second half of her menstrual cycle and remain high if pregnancy occurs. It is often cited as the “feel-good” hormone responsible for the “glow” of pregnancy. If a woman does not ovulate, her progesterone levels may be low. In post-menopausal women, progesterone levels are low relative to premenopausal years.
Progesterone is often a precursor hormone for other sex steroids including testosterone, estrogen and androstenedione as well as cortisol. While estrogen prevents bone loss, progesterone promotes bone formation by stimulating osteoblasts (bone cells) and exerts neuroprotective effects on the brain. Natural progesterone tends to have a calming effect on mood and emotions.
Studies indicate progesterone may be beneficial in treating brain injuries since it reduces enzymes that cause inflammation in the brain after injury or stroke. Progesterone shows a synergistic effect with vitamin D, which is actually a precursor to all sex hormones, on quelling inflammation in brain tissue. Evidence also suggests that vitamin C may increase progesterone levels.
In addition, progesterone does not oppose the beneficial effects of estrogen such as an increase in high density cholesterol, which is heart protective. Progesterone selectively inhibits estrogen in perfectly orchestrated hormonal balance. Similarly, thyroid hormones and progesterone interact with each other to regulate metabolism.
Progesterone inhibits the enzyme aromatase, which converts testosterone to estrogen. As a result, progesterone may serve to conserve testosterone and increase libido in some women. In men, the reduction of this enzyme by progesterone may help reduce hyperplasia (tumors) in the prostate. Men typically have progesterone levels similar to levels seen in women in the first half (follicular phase) of their period.
Progesterone refers to the naturally occurring hormone found in the human body and should not be confused with progestins, which are synthetic and do not have the same biological activity. The effects of progesterone are often totally different than progestins, which are typically found in oral contraceptives and conventional hormone replacement.
Several other sex hormones exist but are less commonly known by most patients. For example, the most common steroid (aka sex hormone) in the body is DHEA, which stands for dehydroepiandrosterone sulfate. It exists at levels 20 times other hormones and interestingly, it is produced in the adrenal glands, not in sex organs. This is commonly considered a major precursor hormone, meaning that it is used in the synthesis of all other sex hormones. Its synthesis is highly dependent on the availability and function of several micronutrients. In other words, micronutrients are the foundation of the foundational hormones.
Learn more about the importance of micronutrients in your hormone health:
For more information on the link between Micronutrients and Estrogen, click here.
For more information on the link between Micronutrients and Testosterone, click here.