LIVE MASTERCLASS: How to build stronger bones in midlife

REGISTER NOW

The Confusion Around HRT and Cancer: Here’s What You Need to Know

Let’s talk about the hormone that gets blamed for just about everything after 40: estrogen.

If you’re in perimenopause or menopause, you’ve likely been told that estrogen is dangerous. Or risky. Or flat-out deadly if there’s a history of breast cancer. And that kind of fear sticks. Believe me, my mother died of breast cancer when she was only 57, so I was also fearful of hormones…until now.

The story around estrogen and cancer is full of half-truths, outdated research, and a lot of unnecessary panic. It’s time we set the record straight.

This isn’t about ignoring risk. It’s about finally understanding the full picture, so you can make decisions based on facts, not fear.

First, a little hormone reality check

Estrogen isn’t some rogue villain. It’s a hormone your body relies on to keep bones strong, your brain sharp, your heart protected, your sleep deeper, and your vagina and bladder functioning comfortably. If it were that horrible, we would all be dead at age 20 when our hormone levels peak.

When estrogen drops during peri-menopause, everything from joint pain to hot flashes to brain fog to mood changes can kick in. It’s not just about reproductive health. It’s about your entire system.

So when doctors refuse to even discuss hormone therapy because of a blanket fear of cancer, they’re not doing you any favors. Women deserve better than outdated rules and one-size-fits-all care.

A not-so-fun history lesson

Back in 1896, Dr. George Beatson discovered that removing ovaries could shrink certain breast tumors. It only worked in about 30 percent of women, but it started the trend of treating breast cancer by stripping estrogen from the body.

Fast forward to the 1940s, and scientists started giving women high-dose estrogen therapy instead. Same success rate. Roughly 30 percent.

Yes, you read that right. First we removed estrogen. Then we added a ton of it. Both approaches had limited but similar results. So clearly, the relationship between estrogen and cancer isn’t black and white.

The age of anti-estrogen drugs

In the 1970s, tamoxifen entered the scene. It was originally developed as a contraceptive but turned out to be more effective at blocking estrogen receptors in breast tissue. It helped slow tumor growth in some women, so it became a standard treatment.

Later, aromatase inhibitors were developed. These drugs lower estrogen even more by preventing the conversion of testosterone into estrogen. Sounds promising, but here’s the problem.

Estrogen was already low in postmenopausal women. So blocking it further doesn’t always make sense. Especially when we now know that many breast cancers don’t even respond to this strategy.

In fact, anti-estrogen drugs like tamoxifen and aromatase inhibitors only work in 30 to 50 percent of cases. That means 50 to 70 percent of tumors don’t respond at all.

Resistance, explained

Prof. Dr. Zsuzsanna Suba, a clinical cancer geneticist and oncological researcher, broke this process down into three phases

Phase one is where treatment seems to work. Estrogen levels drop, the body ramps up receptor sensitivity, and the tumor shrinks.

Phase two is the plateau. The tumor doesn’t grow, but it doesn’t shrink either. It’s the body trying to adapt.

Phase three is when things go off the rails. After long-term estrogen deprivation, the tumor can actually grow faster and more aggressively.

This is called “acquired resistance”. In some cases, reintroducing estrogen after resistance develops can actually shrink the tumor again. Which tells us estrogen itself is not the enemy. The context matters.

Estrogen does more than we were told

A 2022 study by Dr. Lia Yedidia-Aryeh, a molecular geneticist based at The Hebrew University of Jerusalem, found that estrogen supports DNA repair by enhancing homologous recombination pathways and reducing accumulation of DNA damage  

This means that when estrogen is too low, cells become more vulnerable to damage and mutation. That’s a big deal. And it contradicts the old idea that less estrogen is always better.

We’re finally seeing research that paints estrogen in a new light. Not as a universal risk, but as a protective hormone that plays a crucial role in maintaining health across multiple systems.

So why the ongoing fear?

Because the fear narrative is easy. And old ideas are hard to shake.

But let’s not forget that other factors drive breast cancer too. Like inflammation, insulin resistance, environmental toxins, synthetic estrogens (like ethinyl estradiol in birth control), and certain genetic mutations. Blocking estrogen doesn’t address those.

Yet somehow, estrogen has become the scapegoat.

What you actually need to know

Every woman deserves to understand her options. Hormone therapy is not a blanket yes or no decision. There are different types of estrogen, different delivery methods, and different risk profiles.

There are also non-hormonal ways to support your body if HRT truly isn’t an option. But making that decision out of fear, rather than informed choice, is what gets us into trouble.

This is your body. Your future. Your health.

If your doctor won’t discuss hormone therapy because of breast cancer history, then ask questions. What kind of cancer? What were the receptors? What’s the actual individual risk? Are we talking about oral synthetic estrogen or a low-dose vaginal bioidentical cream? What are the risks if I DON’T choose hormone therapy?

These details matter. A lot. Grab the “Menopause Questions Checklist” that includes the questions to ask your menopause doctor on that first visit…and what your doctor should be asking you too!

Bottom line

Estrogen is not automatically dangerous. The war on estrogen was built on limited science and fear-based medicine.

Today, we have better tools, better research, and better ways to personalize care. That means smarter decisions and more empowered women.

So if you’ve been confused about hormones and cancer, now you know. It’s complex. But it is manageable. And you don’t have to be scared of your own biology.

If you want help navigating all of this, come join us inside the Biohacking Menopause community. We break it all down so you can take action with confidence and you will find more resources to guide you through your journey.

Because menopause isn’t the end. It’s a beginning. Let’s make sure it’s a strong one.

Further Resources on Breast Cancer and HRT

Doctors

Books

Articles by Dr. Jeffrey Dach MD

Leave your comment

<