Terminology: Estrogen (American spelling) and oestrogen (UK spelling) refer to the same thing.
What Is Estrogen?
It is a hormone primarily produced (along with progesterone) by the ovaries. The word hormone comes from the Greek word hormao meaning 'I stir up' or 'I set in motion'. Estrogen is responsible for the development of the female body in puberty: the growth of breasts, pubic hair and the start of menstruation. It is essential for the menstrual cycle and maintaining a healthy pregnancy. Levels of estrogen fluctuate as we approach menopause resulting in menopause symptoms like hot flashes and night sweats until the body eventually adjusts to functioning on lower levels. The word estrogen in fact is a generic umbrella term, the hormone comes in a variety of different forms including estradiol, estrone and estriol (there are at least a further 17 minor kinds). Estradiol is the main type of estrogen produced by women of childbearing age and is important for menstrual cycles, pregnancy and bone health. It is the type most often linked to gynecological disorders like endometriosis and fibroids and female cancers. Estriol is created by the placenta in pregnancy and estrone is the only estrogen thought to remain in the body after menopause.
Where In The Body Is It Produced?
Estrogen is manufactured mostly in the ovaries but it is also produced by the placenta during pregnancy. The liver, breasts and adrenal glands also contribute to levels, but in much smaller quantities.
Relationship Between Obesity And Estrogen
Although estrogen is primarily made in the ovaries, other sources include adipose or body fat tissue. Studies show that underweight women are less likely to have enough estrogen in their body and as a consequence suffer from menstrual irregularities (dysmenorrhea) and fragile bones. Conversely, obese women can suffer from an excess level of estrogen which can lead to reproductive system disorders like polyps, fibroids, endometriosis and breast cancer. Yet being overweight has one upside when you approach menopause. While the ovaries are cranking down estrogen production, your body fat will help to keep production levels more stable, so you are less likely to suffer from hot flashes and other menopausal problems. The downside: being overweight exposes you to a host of other health problems from arthritis and type 2 diabetes to heart disease and cancer.
What Is The Function Of Estrogen?
At puberty a hormone called FSH (follicle stimulating hormone) is produced by the pituitary gland and kick starts the ovaries into producing estrogen. This increased level of estrogen accounts for the developments that take place in the a girl's body during puberty: growth of her breasts, vagina, fallopian tube and uterus; increased layers of body fat and their distribution and growth of bones of the body (arms, legs, hands and feet) and pubic and underarm hair. The average age of puberty in America for a girl is 12.5 years.
For the next 35 years or so the levels of estrogen rise and fall each month during the menstrual cycle; and drop if fertilization does not occur. All hormones are like little chemical messengers that travel through the blood stream issuing orders to cells. The presence of increased estrogens 'tell' the lining of the uterus to thicken in preparation for receiving a fertilized embryo. If an embryo does not implant estrogen levels decline and the lining of the womb breaks down resulting in a period.
Estrogen levels peak and remain constantly high during pregnancy. Human chorionic gonadotropin (HCG), sometimes referred to as the pregnancy hormone makes an appearance soon after conception and doubles about every 2 days during the first 10 weeks. HCG keeps estrogen (and progesterone) at appropriately high levels until the placenta has developed enough to take over the function. After childbirth, when the placenta has been delivered with the baby, hormone levels come crashing down again. This can lead to a bout of baby blues, a temporary emotional phase common in the days after childbirth.
In the years approaching menopause (perimenopause) the ovaries role of egg production is naturally coming to an end. In response they start to gradually shut down their production of estradiol (this process can take 10 years or so). Initially the brain panics thinking there is something wrong and sends out bursts of adrenaline to kick-start the system. The ovaries respond by temporarily cranking up production before falling again. Then the cycle repeats itself. These fluctuations can cause hot flashes, bouts of diarrhea, flutters in the stomach - and even fertility peaks (responsible for many unexpected pregnancies in women in their early 40s who assumed their days of fertility were gone).
For more, see: How menopause affects the body.
Menopause is technically reached when you have stopped menstruating for 12 consecutive months. From this point onwards, all fertility is lost. Hormone levels start to settle down at a lower level, moods swings stabilize and hot flashes subside (although it could still take a few years for complete stability). Recent studies indicate that while the ovaries no longer produce estradiol after menopause, they still produce lower levels of estrone (any estradiol remaining in circulation will be converted to estrone). The role of estrone is less clear.
Other Functions Of Estrogen
• Maintains bone density (which is why osteoporosis is a risk for postmenopausal women).
• Keeps the skin and vaginal lining elastic (see menopause skin problems).
• Protects from heart disease by raising HDL (good) cholesterol levels. Estrogen delays the aging of the circulatory system and slows the process of atherosclerosis. This is why the risk of heart attacks in women increases after menopause and eventually equals that of men.
Estrogen was discovered by scientists in 1915, and within 15 years the first synthetic estrogen was produced by pharmacists. Both natural (obtained from the urine of pregnant horses) and synthetic forms (made in a laboratory) of estrogen are administered for a variety of purposes. They are used in oral contraceptive pills to prevent pregnancy, in the treatment of menopause symptoms (estrogen replacement therapy, ERT), to suppress lactation in women who do not want to breastfeed, to treat menstrual irregularities and to treat some forms of female cancers. Supplemental estrogen can cause side effects such as a bloated stomach, nausea, vomiting, headaches, breast tenderness and abnormal vaginal bleeding. The side effects can depend on the dose (for example the morning after pill contains a much higher dose than an ERT pill) and individual reaction. Those with a risk factor for breast cancer, blood clots, hypertension, diabetes, endometrial cancer and gallbladder disease should carefully weigh up the pros and cons of estrogen therapy with their doctor as some types of estrogen can increase the risk of these diseases.
What Is Estrogen Dominance?
While estrogen is clearly an essential hormone for women, too much of a good thing can actually be bad. Hormones are like little chemical messengers that shoot around the body passing on instructions to cells in the body. If there is an imbalance in these hormone levels, messages may not be delivered, or the message may be confused - manifesting in physical problems. Excess levels of estrogen is referred to as estrogen dominance. It raises the risk of:
• Rampant PMS symptoms such as hot flashes, sore breasts, anger and irritability.
• Missed periods (amenorrhea).
• Mental confusion and decreased cognitive (thinking) ability.
• Uterine fibroids.
• High cholesterol.
• Fibrocystic breast disease.
• Ovarian cysts.
• Uterine (womb) and breast cancer.
• Heart disease and stroke.
• Weight gain, particularly around the tummy and waist, secondary to insulin resistance.
Causes Of Excess Estrogen
Bad Diet: Many researchers think that eating a diet high in fat and low in fiber increases the kinds of estrogen associated with breast cancer. It also increases the risk of estrogen being reabsorbed into the body if stool remains in the bowels for a long time due to constipation.
Environmental toxins: Certain hormone mimicking chemicals called xenoestrogens found in plastics, some cosmetics, pesticides, personal care products and gasoline have an estrogen-like effect if they pass into the bloodstream - they can also recycle natural estrogen present in the body into a more aggressive form linked to diseases like breast cancer. Hormone residues in meat and dairy can also have an estrogenic effect.
Liver problems: The liver is responsible for cleaning the blood and dumping toxins for excretion into the kidneys. If the liver is over-taxed with work due to bad diet, alcohol or drugs, its performance is affected. Studies show estrogen levels increase by up to 32 percent in women who consume just 2 alcoholic drinks a day.
How To Reduce Estrogen Levels Naturally
1. Lose weight if you need to. Excess body fat can lead to excess estrogen.
2. Exercise regularly, it helps to curtail estrogen over production. Although extreme exercise, known as female athletic triad can abolish production altogether, it's not something most of us need to worry about!
3. Dietary supplements like Indole 3 Carbinole and Methylsufonylmethane (MSM) can help estrogen metabolize better. A rising star supplement called Brevail, which contains flaxseed lignans, appears to support hormone health.
4. Eat more fiber. Aim for 10 to 20 grams daily.
5. Avoid any food which naturally increases estrogen levels, or which recycles estrogen into a more aggressive form. See, our fibroids diet plan for anti-estrogen foods.
Can I Test My Estrogen Levels?
Yes, your doctor can perform either a blood or urine test to check estrogen levels. A test is more commonly performed to:
• See if raised levels are responsible for fibroids, endometriosis or other gynecological disorder in a patient.
• Diagnosis an ovarian tumor or Turner syndrome (cause of underdeveloped female sexual characteristics).
• Diagnose cause of missed periods (is it a medical problem, pregnancy or menopause?).
• Monitor the effectiveness of assisted reproductive technology (ART) prior to IVF.
• Monitor the effectiveness of HRT.
• Monitor a high risk pregnancy. Part of a triple or quad screen, decreased levels of estriol are associated with genetic disorders such as Down syndrome and neural tube defects.
It is also possible to buy a home test kit online, such as the Estradiol (E2) Saliva Hormone Level Imbalance Testing Kit by ZRT Lab and Saliva Hormone Test Female (5 Hormone Test Kit) by testMyHormones.com
What The Results Mean
Raised estrogen levels are seen in:
• A normal menstrual cycle (mid-cycle).
• Early (precocious) puberty.
• Ovary or adrenal gland tumors.
• Cirrhosis of the liver.
Low levels of estrogen are seen:
• Naturally after menopause (estradiol).
• Turner syndrome.
• Hypopituitarism (decreased hormone production by the pituitary gland).
• Hypogonadism (decreased ovary hormone production).
• Failing pregnancy (estriol).
• Extreme performance exercise.
Low levels of estrogen (deficiency) can start early in a girl's menstrual history, these girls have difficult periods from the start and often need to take birth control pills to regulate the frequency and severity of their periods. Others will develop it later in life as the result of diet, illness or anovulatory cycles (no ovulation has occurred) before menopause.