What did @fit2fat2fit actually say?
The creator claims his free testosterone started at "9.6" and is now "213," framing the original number as alarmingly low. He also notes his total testosterone was 458, which he puts in quotes as "normal." The implication is that total testosterone numbers can be deceptive, and that free testosterone tells a more urgent story. That framing is actually worth taking seriously.
To be precise about what was said: "My free testosterone...was 9.6. Now it's in the green at 213." He does not specify units, which matters a lot here. Free testosterone is typically reported in pg/mL or pmol/L depending on the lab, and the reference ranges are wildly different between the two. That missing detail is not a small thing when you're using numbers to make a clinical point on social media.
Does the science back this up?
The broader point, that total testosterone is an incomplete picture, is supported by research. Free testosterone, the fraction not bound to sex hormone-binding globulin (SHBG) or albumin, is what's actually bioavailable to tissues. A man with a total testosterone of 458 ng/dL but high SHBG can have free testosterone well below normal range, and symptoms to match.
Rosner et al. (2007, Journal of Clinical Endocrinology and Metabolism) argued that free testosterone measurement provides clinical information beyond total testosterone, particularly in men with conditions affecting SHBG. The Endocrine Society's clinical practice guidelines acknowledge that some symptomatic patients with normal total testosterone but low free testosterone may benefit from treatment. A 9.6 pg/mL free testosterone reading in a symptomatic adult male would fall below most lab reference ranges, which typically bottom out around 35-155 pg/mL. If his number was in pg/mL, that is genuinely low. The post-treatment value of 213 pg/mL would sit in the mid-to-upper normal range for most labs.
What did they get wrong (or right)?
They got the underlying clinical concept right. Free testosterone matters, and a total in the "normal" range does not rule out functional hypogonadism. That's legitimate and underreported in general health content.
What's missing is units and context. Without knowing the assay used, 9.6 could mean very different things. The gold standard for free testosterone measurement is equilibrium dialysis, but most commercial labs use calculated free testosterone or analog immunoassay methods, which have known accuracy limitations. Vermeulen et al. (1999, Journal of Clinical Endocrinology and Metabolism) showed that analog immunoassay free testosterone measurements can be unreliable, particularly at low concentrations. So when the creator treats 9.6 as a precise, alarming number, the measurement method matters enormously. He doesn't address that, and neither do most TRT content creators.
The jump to 213 after TRT is plausible and consistent with expected outcomes. That part checks out.
What should you actually know?
Free testosterone testing is genuinely useful but also genuinely messy. The number your lab prints means little without knowing the method behind it. If your doctor or telehealth provider is making treatment decisions based on a calculated or immunoassay free testosterone without considering symptoms and clinical context, that's worth asking about.
TRT can meaningfully increase free testosterone, and symptom improvement is real for many men with documented low levels. But the decision to start TRT involves weighing real risks, including effects on fertility, hematocrit, cardiovascular risk, and endogenous testosterone suppression. Bhasin et al. (2010, New England Journal of Medicine) found increased cardiovascular events in older men on testosterone therapy, a finding that continues to shape clinical caution even if later data have been more mixed.
One creator's before-and-after is not a clinical trial. His experience may be genuine. It is not a template for your own lab results.
- Free testosterone reference ranges vary by lab and method. Always ask which assay was used.
- A "normal" total testosterone does not rule out symptomatic low free testosterone.
- TRT is a regulated medical decision, not a wellness upgrade. It requires ongoing monitoring.
- Compounded testosterone products are not equivalent to brand-name formulations. Do not assume interchangeability.