Why Women and Men Both Need Estrogen and Testosterone

This note is about hormones, and it’s one I care about a great deal. Receptors for estrogen and testosterone sit in nearly every tissue in the body, so when levels fall, the effects reach far beyond hot flashes and sex drive. Women and men need both, in different amounts. If the men’s half isn’t about you, it may well be about someone you love.

Why women need both

For most women the shift starts in the 40s, during perimenopause, often years before the last period. Estradiol is the body’s most potent estrogen, and it protects the heart, bones and brain, especially when it’s started early. Testosterone is the most abundant active sex hormone in a woman’s body, and it supports energy, mood, libido, muscle and bone. If you still have a uterus, progesterone protects its lining.

A lot of the fear around estrogen goes back to one study from 2002, the Women’s Health Initiative. When its first results made the news, the message women heard was that estrogen was dangerous, and many stopped treatment or never started it. Some spent years with hot flashes, poor sleep and bone loss that treatment could have helped. Of everything I do, this is the part I feel most strongly about.

Here’s what most people never heard about that study. It tested a horse-derived estrogen with a synthetic progestin, in women who were 63 on average and often more than ten years past menopause. It didn’t test estradiol. And when researchers followed those women for 18 years, they found no increase in deaths from any cause, heart disease or cancer. Too few women have heard that part. The estradiol I prescribe is the same molecule your ovaries made.

Why men need testosterone, and some estrogen too

Testosterone is a man’s main sex hormone, and when it falls the effects reach far beyond libido: energy and drive, muscle and strength, sleep, mood and focus. In long-term studies, men with low testosterone have more heart disease, more dementia and shorter lives. Men need some estrogen too. Part of your testosterone turns into estradiol, which protects your blood vessels, brain and bones, so I don’t block it as a routine.

Then there’s the prostate. In TRAVERSE, a trial of 5,204 men who took either testosterone or a placebo for about two years, high-grade prostate cancer was rare and no more common on testosterone. I still check your PSA before you start if you’re over 40, and every year after that. Testosterone also lowers sperm production and raises red blood cells, so tell me if you still want children, and we watch your blood count along the way.

Labs come first

None of these symptoms proves a hormone problem on its own, which is why we test before we treat. From there I treat your symptoms, use your labs as the guide, and adjust the dose as we go. Pellets are our primary approach for patients who fit them, because they release steadily for months with nothing to remember between visits. Injections, creams and patches are options too, and we choose the route together. (Compounded pellets aren’t approved by the FDA. Approved forms of these hormones are available too, and I’ll go through them with you.)

The two sheets I give patients

Everything above comes from two sheets I wrote for patients, one for women and one for men. They cover what an email can’t: the studies behind each point, the lab numbers we aim for, and how the different routes compare. Each is four pages and prints on regular paper.

Please pass these along. If someone you love comes to mind while you read this, forward them this note or print them the sheet that fits. Every woman over 40 deserves to have this information, and so do the men in their lives.

What it costs. Pellet therapy is $375 a procedure for women and $700 for men, with labs billed separately. Injectable testosterone for men is $399 to start, then $199 a month, all-inclusive. HSA and FSA cards are accepted.