Reading a hormone panel: what TRT influencers get right and wrong

What did @harveylonsdale_ actually say?

The creator walks viewers through a standard hormone panel, covering FSH, LH, estradiol, total testosterone, free testosterone, and prolactin. The framing is aimed at guys starting TRT or their "first cycle" who receive lab results and have no idea what they mean. Fair enough, that's a real gap. He explains that LH signals testosterone production, FSH triggers androgen-binding protein (ABP) production, and that ABP binding to testosterone creates sperm. He then notes that on exogenous testosterone, FSH and LH will "be in the bin," and that estrogen and prolactin levels depend on individual factors and lifestyle. He correctly separates total from free testosterone, calling total testosterone "kind of pointless" on TRT.

The intent is educational and the delivery is casual. But several of the biological claims underneath the plain-English packaging have real accuracy problems worth unpacking.

Does the science back this up?

Partially. The FSH/LH suppression point is solid. The ABP-sperm claim is where things fall apart, and calling total testosterone "pointless" on TRT is an oversimplification that could mislead people managing their health. The prolactin section is vague to the point of being nearly useless.

On suppression: exogenous testosterone reliably suppresses gonadotropins through negative feedback on the hypothalamic-pituitary axis. This is textbook endocrinology and is well-supported by clinical data, including the landmark hypogonadism trials summarized by Bhasin et al. (2010, New England Journal of Medicine). Expect FSH and LH to drop significantly on TRT. That part is accurate.

On estrogen: the video says levels "depend on how much you aromatize," which is roughly correct. Testosterone converts to estradiol via the enzyme aromatase, with conversion rates varying by body composition, genetics, and dose. Camacho et al. (2013, Journal of Clinical Endocrinology and Metabolism) confirmed that higher adiposity increases aromatase activity, which is why estrogen management is not one-size-fits-all.

What did they get wrong (or right)?

The ABP explanation is where the science goes off track. The creator says FSH stimulates ABP production, that ABP binds testosterone, and that this "creates sperm." This conflates several separate processes. ABP (androgen-binding protein) is produced by Sertoli cells in response to FSH and serves to concentrate androgens locally within the testes to support spermatogenesis. It does not create sperm. Sperm production is a multi-step process requiring FSH, testosterone, and functional Sertoli and Leydig cells. ABP is a facilitator, not a factory. Calling total testosterone "kind of pointless" on TRT is also too strong. While free testosterone is the biologically active fraction, total testosterone remains a useful clinical marker, especially when tracking dose adequacy, conversion rates, and for comparing against population reference ranges. Petak et al. (2002, Endocrine Practice) recommend monitoring both.

What he got right: the free testosterone distinction is genuinely important and under-discussed. The point that prolactin elevation can contribute to erectile dysfunction is supported by clinical literature, including Corona et al. (2012, Journal of Sexual Medicine).

What should you actually know?

If you're reading a hormone panel on TRT, here's what actually matters. FSH and LH dropping toward zero is expected, not alarming. It reflects suppression of the HPG axis. Estradiol monitoring is legitimate but the threshold for concern is individual. The idea that all estrogen is bad is a persistent myth in TRT communities with no serious clinical backing. Symptoms matter more than a single number. Free testosterone is the more functionally relevant metric, but your clinician will still track total testosterone for the full picture. Do not bin that number.

Prolactin elevation can come from several sources: pituitary adenomas, certain medications (antipsychotics, antiemetics), sleep deprivation, and stress. Lifestyle plays a role, but attributing high prolactin purely to "lifestyle choices" without ruling out pathology is premature. Anyone with consistently elevated prolactin should get imaging discussed with their doctor. If you're managing your hormone health on TikTok tutorials alone, that is a problem this video can't solve.