“Dr. Brett Wisniewski practices a model of diagnostics, natural therapeutics, and true patient partnership. He believes medicine should move beyond symptom suppression and instead focus on understanding the physiology driving the complaint. One of the first question to answer in any condition is, “What shifted in the body to create this pattern?” His work centers on identifying upstream contributors metabolic stress, immune dysregulation, hormonal imbalance, environmental load, and nervous system dysfunction, and developing personalized strategies that restore function and build long-term resilience.”
If you haven’t read part I of this article please click here to bring yourself up to speed!
Serum, Saliva, Urine: When Each One Actually Earns Its Keep
Let’s put it all together, because different testing methodologies genuinely shine in different situations, and the “right” test depends entirely on the question you’re asking. It would be best to ask your doctor which test is right for you whether you are just trying to get a baseline or monitoring therapy, each method of testing has its pluses and minuses.
Serum (blood): This is still the workhorse for establishing baseline hormone status, diagnosing frank deficiency or excess. Serum levels are circulating hormones, traveling to your tissues. This is good for monitoring most form of HRT but can show extreme peaks in some categories of patient such as those injecting hormones intramuscular (IM) so timing of this test will be important for those folks.
Saliva: Its strength is capturing the free, bioavailable fraction of a hormone, which makes it a reasonable general-health tool for cortisol rhythm testing and, importantly, for patients on transdermal (cream or gel) hormone therapy. Here’s the twist most patients have never heard: topically applied hormones behave strangely in the body. Progesterone and testosterone creams are absorbed into subcutaneous fat and delivered to tissues largely via red blood cell membranes rather than the watery portion of blood that serum testing measures so serum levels on topical therapy can look almost unchanged even when tissue delivery has increased dramatically, while saliva (and capillary blood spot) levels rise substantially and track tissue exposure far more faithfully. Multiple published comparisons have found this discrepancy is not small: serum can underrepresent topical dosing by an order of magnitude compared to saliva or capillary blood. If your provider is monitoring your progesterone or testosterone cream dose using a standard venous serum draw, there’s a real chance they’re chasing the wrong number.
Urine (dried or 24-hour): As we’ve covered, its real strength isn’t moment-in-time hormone status, it’s the metabolic and clearance picture. Best uses characterizing estrogen metabolite ratios for cancer-risk-relevant pathway assessment, evaluating adrenal cortisol metabolite patterns over a full day rather than a single draw, and monitoring clearance efficiency in patients already established on HRT of any delivery method. It is a poor tool for establishing baseline hormone deficiency or titrating a starting dose, and per the point above, its accuracy depends on liver and kidney function being reasonably intact.
if a provider is running a urinary hormone metabolite panel as your only hormone test and adjusting your HRT dose based on it alone, that’s an incomplete clinical picture. It’s not malicious, usually, it’s more often a shortcut born from convenience, marketing, or not having been taught the distinction.
A reasonable question for your provider: “Are we looking at my actual circulating hormone levels, or only at how I’m metabolizing them?”
The gold standard, when it’s feasible, is running both: circulating hormone levels (serum, or saliva) and urinary metabolites. One tells you what’s available. The other tells you what your body is doing with it once it’s finished being used. Together, they complete the picture. Separately, either one is half a conversation.
Running both isn’t always practical. Cost, insurance coverage, patient bandwidth for multiple collections, these are real barriers, and we shouldn’t pretend every patient needs every test every time. But “not always feasible” is a reason to be thoughtful about which single test best answers the specific clinical question in front of you. It is not a reason to default to the metabolite panel and call the hormone conversation finished.
So What Is the Urinary Metabolite Panel Actually Good For? A Lot…
Estrogen doesn’t just get metabolized one way. It gets funneled down three competing pathways, nicknamed by the carbon position where your liver’s cytochrome P450 enzymes hydroxylate, attach an oxygen-hydrogen group to, the estrogen molecule: 2-hydroxyestrone, 4-hydroxyestrone, and 16-hydroxyestrone. Think of it like a river hitting a delta and splitting into three channels. Which channel gets the most water matters.
The 2-OH pathway is the relatively benign one, it tends to get methylated (capped off by an enzyme called COMT, catechol-O-methyltransferase, using methyl groups largely supplied by your folate and B12 status) into a stable, inactive form and shown the exit door. The 4-OH pathway is the one most practitioners pay attention to, because 4-hydroxyestrone can oxidize into a quinone, a reactive molecular species that’s capable of forming what’s called a DNA adduct: a spot where the quinone chemically bonds to your DNA and, if it’s not repaired, can generate a mutation. To be precise, because precision matters here: this doesn’t cause cancer on its own. Nobody develops a tumor from a single hydroxylation pathway. But it’s a documented contributor to the cumulative oxidative and genotoxic burden, the background rate of DNA damage and inflammatory signaling your body has to keep repairing, and that burden can build over a lifetime, especially layered on top of other risk factors. Researchers have spent decades mapping exactly this quinone-adduct pathway in estrogen-related cancers, and it’s one of the more mechanistically well-supported pieces of the estrogen-cancer-risk literature.
This is valuable information. If I see a patient shunting heavily toward 4-OH with poor downstream methylation, that tells me something actionable, support methylation capacity, look at glutathione status, consider compounds like sulforaphane or DIM that nudge the ratio favorably, and reassess.
Wait — Aren’t Some Metabolites Hormonally Active Too?
Fair question, and yes, I’ve been talking about metabolites as “what’s left after the hormone did its job,” and for the most part that’s true. But it’s not universally true, and the exceptions are some of the more interesting biochemistry in this whole conversation, so let’s give them their due.
Not every steroid metabolite is a dead end. Some retain meaningful receptor activity, sometimes weaker than the parent hormone, sometimes stronger, and sometimes at a completely different receptor altogether:
- Estrone (E1), the estrogen metabolite most labs report, still binds the estrogen receptor, just with meaningfully less potency than estradiol. It’s a real, even if quieter, estrogenic signal.
- 16α-hydroxyestrone, the third branch of that metabolic delta I described earlier, actually retains substantial estrogenic, proliferative activity of its own, which is part of why practitioners who track the 2-OH:16-OH ratio care about it, separately from the 4-OH/DNA-adduct story.
- Dihydrotestosterone (DHT), technically a testosterone metabolite generated by the enzyme 5-alpha-reductase, is actually the more potent androgen, it binds the androgen receptor roughly two to three times more tightly than testosterone itself and releases from it more slowly. This is the metabolite driving male pattern hair loss and playing a role in benign prostatic hyperplasia, and it’s a good reminder that “metabolite” doesn’t automatically mean “weaker.”
- Allopregnanolone, a metabolite of progesterone, is arguably the most interesting example of all, because it doesn’t act through the progesterone receptor at all. It’s a potent positive modulator of the GABA-A receptor, the same receptor system targeted by benzodiazepines and alcohol, which is the mechanism behind progesterone’s calming, sleep-promoting, anti-anxiety reputation. If a patient tells me oral progesterone helps them sleep in a way topical progesterone doesn’t, allopregnanolone production during first-pass liver metabolism is a big part of that story.
So, the honest, complete version of the point I opened this article with isn’t “metabolites are inert waste products.” It’s that metabolites answer a different biological question than circulating parent hormone does, sometimes because they’re less active, sometimes because they’re differently active, and occasionally because they’re more active at an entirely different receptor. None of that changes the core argument: a urinary metabolite panel still isn’t a stand-in for knowing your circulating hormone status. It just means the biochemistry underneath is even richer than “breakdown product,” and worth understanding on its own terms rather than dismissing.
The HRT Clearance Blind Spot
There’s a second genuinely useful application, and it’s one I wish got more airtime: monitoring clearance in women already on hormone replacement therapy.
When you’re supplementing estrogen, patch, cream, pellet, whatever the delivery method, your liver still has to process every bit of it through those same three pathways. A urinary metabolite panel in that context isn’t telling you your dose (again — not its job). It’s telling you whether your body is clearing the estrogen you’re already taking efficiently, or whether it’s accumulating in a less favorable pathway over time. That’s a clinically meaningful use of the test, and it’s one I use routinely with HRT patients, just alongside, not instead of, knowing their actual circulating levels.
A Word on AI, Because I’ve Noticed It Too
I’ll add something I wasn’t planning to say a year ago: I’ve started noticing AI tools, chatbots, symptom checkers, the whole ecosystem, commonly suggesting the DUTCH test to people asking about hormone symptoms. Often without any of the nuance above.
I’m not anti-AI. I use these tools too. But they’re trained on the internet, and the internet is saturated with DUTCH marketing, wellness-influencer enthusiasm, and functional medicine content that repeats the same “comprehensive hormone panel” framing without interrogating it. Garbage in, garbage out, delivered with AI confidence. Trust, but verify, that applies double when the “expert” giving you lab advice is a language model instead of a clinician who’s examined you and has many years of experience.
The Takeaway
The DUTCH/Urinary Metabolites tests aren’t the villain here. Misapplication is. Used correctly; to understand hormone metabolism, cancer-risk-relevant metabolite ratios, and clearance efficiency in patients on HRT, it’s a legitimately useful piece of a bigger picture. Used as a standalone tool to determine whether your estrogen or testosterone dose needs adjusting, it’s the wrong tool for that job.
If your provider is using it that way, ask why. A good practitioner will have an answer that makes sense. And if the answer is “this is the gold standard of hormone testing”, that’s worth a second opinion, not because the test is bad, but because your doctor may not fully understand what you are interested in. This is the kind of nuance that’s easy to lose in a fifteen-minute visit or a chat with an AI tool, and why a real relationship with a practitioner who actually knows your case is worth more than any single lab report, however comprehensive its acronym claims to be.
