The way we teach the biology of hormones is confusing. From an early age, kids are told that testosterone is a male hormone whereas estrogen is a female hormone. Young men have sometimes been accused of suffering from “testosterone poisoning.” If there is aggressiveness, machismo or just plain bad behavior, it is frequently blamed on too much testosterone. But testosterone and estrogen are essential for both men and women. If levels fall too low, testosterone therapy in women and men may be helpful.
Where Does Estrogen Come From?
It is not unusual for some health professionals to get caught up in the mythology that estrogen is a female hormone, whereas men only make testosterone. Many people are surprised to learn that women require testosterone. This so-called male hormone is an absolutely essential precursor for the creation of estradiol, the most active form of estrogen.
Men make estrogen too in the form of 17β-Estradiol (E2). The key enzyme for both men and women is aromatase. It converts testosterone to estrogen. Without testosterone there can be no estrogen!
Older men and women actually make somewhat similar amounts of estrogen. An adult man creates somewhere between 10 to 50 pg/mL [pg/mL is picograms per milliliter]. A postmenopausal woman makes somewhere between 0 to 30 pg/mL. As you can see, men and women are about comparable when it comes to estrogen production when they become senior citizens.
Prior to Testosterone Therapy in Women, What Is Normal?
Testosterone is a bit more complicated and not all labs agree on “normal.” In general, though, men over 60 make roughly 200-850 ng/dL [nanograms per deciliter]. “Normal” for women ranges from 15 to 70 ng/dL depending on the lab. After menopause many labs consider normal to range from 7 to 40 ng/dL.
You may have noticed that the switch from picograms per milliliter (pg/mL) for estrogen to nanograms per deciliter (ng/dL) for testosterone. That’s because laboratories vary in their “normal” measurements. To even things out a bit, an older man would normally make roughly 40-250 pg/mL of free testosterone and an older woman might be making around 1-7 pg/mL.
Laboratories differ in their interpretation of “normal.” That means you should not take the ballpark ranges listed above literally. Always check with your health care provider to interpret lab values!
Where Do Sex Hormones Come From?
One of the biggest surprises for many people is the role of cholesterol in hormone formation. Cholesterol has been vilified by cardiologists as a bad actor for heart health for decades.
Without cholesterol, however, our bodies cannot make testosterone, estrogen, glucocorticoids such as cortisol or vitamin D. Cholesterol is also an important component of cell membranes and bile acids. If we magically eliminated cholesterol from our bodies, we would not survive.
In both women and men, the body uses cholesterol as a building block for compounds like androstenedione and dehydroepiandrosterone (DHEA). These are then converted into testosterone and dihydrotestosterone (DHT).
In premenopausal women, this happens primarily in the ovaries, where quite a bit of the testosterone created is then transformed into estradiol. Postmenopausal women also make estrogen in other tissues, including the adrenal glands, bones, brain and blood vessels.
Testosterone Therapy in Women or Men?
The FDA has approved estrogen replacement therapy (ERT) for older women to relieve the symptoms of hot flashes associated with menopause. The agency also permits the use of various estrogenic compounds for vaginal dryness (atrophy) and the prevention of osteoporosis.
What the FDA has not allowed, however, is testosterone use in women. This hormone is approved for use in men, but only under very specific and rare circumstances. They include “testicular failure” or pituitary problems that interfere with testosterone production. These can be caused by “tumors, trauma, or radiation.”
The FDA discourages doctors from prescribing testosterone to men or women who simply have low levels of this hormone. But many readers of this column, including health professionals, find this policy somewhat short-sighted.
Off-Label Prescribing of Testosterone Therapy in Women and Men:
TRT (testosterone replacement therapy) has been used off-label for decades to treat men and women with diminished sex drive accompanied by very low levels of this hormone. Some readers have offered testimonials about their experience.
Cynthia wrote:
“I had a post-menopausal decade of depression, low energy, no libido and creeping osteopenia. Two weeks after starting bioidentical hormone replacement therapy—testosterone and estradiol pellets plus progesterone capsules—the sun came out. My doctor does blood work before every pellet refresh, about every four or five months to adjust the dose if needed. She also takes into account how I’m feeling. My bones are now normal, my sex drive is good, and I haven’t had a problem with testosterone side effects.”
Laurie related:
“At 78, I have been using vaginal testosterone and DHEA cream for years. My new cardiologist is pleased that I am using hormone therapy. Stronger bones, higher libido, heart health and stronger body!”
Side Effects of Testosterone Therapy in Women:
No one should undertake any hormone replacement therapy without careful medical supervision from an experienced health professional. The most common complications of TRT are acne, facial hair growth and hoarseness. Monitoring blood levels of hormones can help physicians adjust the dose to minimize side effects.
A reader of our syndicated newspaper column described symptoms of excess testosterone:
“At age 29, I had to have a hysterectomy that included my ovaries. After the fat-stored estrogen left my body (producing horrid hot flashes), I complained to my ObGyn about my missing libido. He wrote me a prescription for an estrogen and testosterone mix.
“I began taking them, but I had strange changes in my body. I developed acne, facial hair, body hair and a low voice. I even began to walk differently. It helped some with sex drive, but I felt less and less feminine and more masculine. I hated it. I don’t think testosterone is worth the worry, even for women without ovaries.”
Do Statins Lower Testosterone Levels?
Statins are the most prescribed drugs in the pharmacy. At last count over 50 million people are taking statin-type drugs such as atorvastatin, pravastatin, simvastatin and rosuvastatin. These drugs have a profound impact on cholesterol synthesis.
Many years ago a retired physician asked us whether simvastatin could affect erectile dysfunction. You can read his question and our answer at this link. We have received pushback from cardiologists, though. And there are conflicting studies on the topic. One of the more recent articles (Lipids, Sept. 2024) was titled:
“Effects of high-intensity statin therapy on steroid hormones and vitamin D in type 2 diabetic men: A prospective self-controlled study”
High-intensity statin therapy has become quite a thing in recent years.
But this study suggests that high-intensity statin treatment can take a toll:
“There was a significant increase in the prevalence of decreased libido (from 22% to 47%, p = 0.001) and a significant decrease in the frequency of sexual intercourse (from 4 [1–8] to 3 [0–4] per month, p = 0.005)…Twenty-two percent of the patients developed gynecomastia [enlarged breasts]. The median total, bioavailable and free testosterone significantly decreased from 15.1 (11.4–17.4), 6.3 (5.0–7.8), and 0.27 (0.22–0.33) nmol/L to 12.7 (10.7–15.9), 5.7 (4.4–7.0), and 0.24 (0.19–0.30) nmol/L, respectively, with no change in FSH and LH levels. Three patients (5%) developed hypogonadism (testosterone <8 nmol/L)… High-intensity statin therapy decreased androgen levels in type 2 diabetic men with significant clinical impact.”
A recent post on this website is titled:
“Statins Diminish Sex Drive and Lower Testosterone“
If you would like to learn more about the pros and cons of statins, especially with regard to heart risk, here is a link. We would also like to learn about your experience with either ERT (estrogen replacement therapy) or TRT (testosterone replacement therapy). The comment section is below. If someone you know might appreciate this article, please share. Thank you for supporting our work.
