Understanding the Lingo

Bioidentical, FDA-Approved, Compounded, and Systemic

Welcome back Substack! Let’s cut through the confusion about terms today. When it comes to hormones—especially in the menopause and midlife space—words like bioidentical, FDA-approved, compounded, and systemic get thrown around a lot. And let’s be honest, sometimes they’re used in ways that make everything murkier rather than more transparent. So, let’s break it down and get the facts straight. Because in order to understand the science, we have to start speaking the language.

Photo by Brett Jordan on Unsplash

Bioidentical: What It Actually Means

Bioidentical means that the hormone has the same molecular structure as your body naturally produces. That’s it. Nothing fancy, nothing controversial. Insulin, thyroid, and vitamin D - all bioidentical. The UK doesn’t use the term; instead using “body identical,” which I like a lot because it is more precise. Bioidentical hormones can be made by compounding pharmacies or by major pharmaceutical companies. They are not some fringe, alternative option—they are standard, well-studied hormones. Estradiol (E2), progesterone (not synthetic progestins), and testosterone are examples of bioidentical hormones. Now, just to complicate things - and stay with me - bioidentical hormones are SYNTHESIZED in factories - so technically they are “synthetic bioidentical” - but most people understand that medications are synthesized, but that doesn’t mean they are “synthetic” or not what is naturally in our body.

Naming hormones bioidentical became rampant after the Women’s Health Initiative study scared everyone off their hormones by overemphasizing risks that weren’t really very significant (thanks to a huge media blitz). Well meaning people starting saying “bioidentical” to help women feel like the hormones were safe. Unfortunately, it has created the false dichotomy that anything synthetic is always bad, and that FDA approved medications (which are bioidentical) are not as good as compounded “bespoke” or more expensive options.

FDA-Approved: The Gold Standard for Safety and Efficacy