10/20/2026
BREAST CANCER AWARENESS MONTH
Let’s talk about something many women have been taught to fear: estrogen.
For years, the conversation around menopausal hormone therapy and breast cancer has often been reduced to one message: “Estrogen causes breast cancer.”
The research tells a much more nuanced story.
In randomized clinical trials, estrogen-alone therapy has been associated with LOWER breast cancer incidence—and in long-term Women’s Health Initiative follow-up, estrogen alone was also associated with LOWER breast cancer mortality in women who had undergone hysterectomy.
A 2024 meta-analysis of 10 randomized trials involving more than 14,000 women reached a similar conclusion: women randomized to estrogen-alone therapy had significantly lower breast cancer incidence overall than those receiving placebo.
But this does NOT mean estrogen is appropriate for everyone—or that all hormone therapy carries the same risk.
And this is where language matters: “estrogen” is an umbrella term. Estradiol is not the same thing as conjugated equine estrogens, and neither should be confused with progestins. There are important differences between these hormones and formulations—nuances that can be confusing even within healthcare.
That’s why we believe the conversation shouldn’t be:
“Are hormones good or bad?”
It should be:
“What does the evidence say, and what is appropriate for THIS woman?”
Functional medicine means looking upstream, understanding individual risk factors, and making informed decisions before symptoms or health concerns become bigger problems.
This Breast Cancer Awareness Month, keep up with your recommended breast screening—and don’t let outdated or oversimplified information keep you from having an evidence-based conversation about your hormones.
Individualized care matters. So does good data.
SOURCES:
Chlebowski RT, et al. JAMA. 2020;324(4):369–380.
Chlebowski RT, et al. Breast Cancer Research and Treatment. 2024.
Chlebowski RT, et al. JAMA Oncology. 2015;1(3):296–305.