Estradiol

What is Estradiol?

Estradiol (E2) is the most potent and predominant estrogen in premenopausal women, produced mainly by the ovaries. In men, small amounts are produced by aromatase conversion of testosterone in adipose tissue, brain, and bone. Estradiol is essential for bone density, cardiovascular protection, brain function, and reproductive health in both sexes.

What might a high or low Estradiol mean?

In women, estradiol fluctuates dramatically with the menstrual cycle and drops precipitously at menopause, causing hot flashes, bone loss, and cardiovascular risk increase. In men, estradiol is needed for bone health and brain function, but excess (from obesity-driven aromatization) can cause gynecomastia, water retention, and suppressed testosterone via negative feedback.

What can affect Estradiol?

It may be higher with: Obesity (more aromatase in adipose tissue), Aromatization of testosterone, Estrogen-containing medications/HRT, Ovarian stimulation, Liver disease (impaired clearance), Alcohol. It may be lower with: Menopause (primary cause in women), Aromatase inhibitors (anastrozole, letrozole), Weight loss (less aromatase), Intense exercise, Low body fat, Smoking.