For females, estrogens are a necessity for over 400 functions in the body—including being essential for fertility and reproduction, proper breast development, healthy skin, vascular health and bone health. They also play a role in blood coagulation and the metabolism of cholesterol.
There are over 30 different forms of estrogen, but only three are considered primary estrogens: E1, E2 and E3.
Estrone (E1) is a weak estrogen formed from estradiol (E2). Due to a shortage of estradiol (E2) after menopause, estrone (E1) becomes the primary estrogen during the postmenopausal years.
It is often considered the "bad form of estrogen" that can lead to ill health, including heart, bone and cellular unhealth. It seems the diminished estradiol levels from menopause have something to do with this effect, so let’s take a look at what estradiol does.
Estradiol (E2), which is made primarily in the ovaries, is the most active form of estrogen and almost always prevails in the female body--until menopause, that is. It facilitates proper ovulation, conception and pregnancy. Estradiol also promotes healthy bone structure as well as healthy cholesterol level regulation.
Estradiol sets the trajectory for the menstrual cycle, can help support well-being during menstruation and modulate menopause. Estradiol also functions in breast tissue health and overall skin health.
Additionally, estradiol helps lower LDL (the bad cholesterol) and total cholesterol levels, but helps increase HDL (the good cholesterol), while lowering the risk of developing heart disease.
As mentioned earlier, during the menopausal years, estradiol levels drop so that estrone becomes predominant. This decrease in estradiol is often punctuated by hot flashes and/or night sweats. If other estrogens and hormones are not healthily balanced, then the estradiol drop can increase woman’s risk for heart disease as well as increase her rate of bone loss.
Let’s move on to E3. Estriol (E3) is a weak estrogen—a breakdown estrogen from estradiol—that is made primarily in the placenta and is predominant during pregnancy. Estriol levels begin to increase during the eighth week of pregnancy and continue until shortly before the baby is delivered.
While we’re at it, let’s not forget that progesterone is a precursor for natural estrogen, but menopause causes cessation of ovulation and too little progesterone production. With the lack of progesterone, estrogen—particularly estrone (E1) which prevails after menopause—can become dominant, leading to unhealthy hormonal levels.
The key to overall hormonal health is balance. How’s your estrogen equilibrium these days?