TRT 'no results' claims: what fitness coaches get wrong

What did @zacsmithfitness actually say?

Zac Smith, who identifies as a 10-year coach for men over 35 on TRT, argues that stalled results on testosterone replacement come down to four overlooked factors: unchecked fasting insulin, poor estrogen management, chronically elevated cortisol, and a nutrition plan not built for someone on exogenous testosterone. His pitch ends with a direct-to-DM sales funnel for his "enhanced man protocol."

He's not claiming TRT doesn't work. He's claiming most men running TRT are leaving results on the table because their clinics stopped at the prescription. That's a more specific argument than the usual TRT hype content, and it deserves a specific response.

Does the science back this up?

Partially, yes. The insulin and cortisol points have real mechanistic support, though his framing oversimplifies them. The estrogen claim is mostly accurate but buried under a common oversimplification about anastrozole use.

On insulin: chronically elevated fasting insulin is associated with reduced sex hormone-binding globulin (SHBG), which affects free testosterone availability. Research from Ding et al. (2006, JAMA) found that insulin resistance was independently associated with lower testosterone levels in men. That connection is real. But saying high insulin means your body "can't utilize the testosterone you're injecting" is a stretch. Free testosterone bioavailability is the mechanism, and it's more nuanced than he makes it sound.

On cortisol: glucocorticoids do suppress the hypothalamic-pituitary-gonadal axis, but men on exogenous TRT have already bypassed HPG suppression at the testicular level. Cortisol still matters for body composition and recovery, but the direct "competing with testosterone" framing is imprecise. A 2021 review in Frontiers in Endocrinology confirmed the cortisol-testosterone antagonism, but mostly in endogenous hormone contexts.

What did they get wrong (or right)?

The estrogen section is where Smith is most correct and most careless at the same time. He's right that indiscriminate anastrozole prescribing is a real problem in TRT clinics. Studies including Finkelstein et al. (2013, NEJM) confirmed that estradiol plays a significant role in male libido, fat distribution, and bone density. Crashing estrogen with AI overuse is a documented clinical error.

But his claim that "neither having high estrogen or low estrogen is good" and that it's about a "ratio between test and estrogen" conflates two things. The testosterone-to-estradiol ratio is a real clinical marker, but the optimal range is not a single universal target. Individualizing it matters, and no fitness coach, regardless of experience, should be the one calibrating that without bloodwork reviewed by a licensed provider.

The "nutrition plan for an enhanced man" claim is where the content moves from oversimplification into vague upselling. He offers no specifics, no research, just a product hook. That's not a protocol. That's a pitch.

What should you actually know?

If you're on TRT and not seeing results, the four variables Smith names are worth asking your prescribing provider about. Fasting insulin, estradiol, cortisol, and dietary protein are all legitimate parts of a thorough workup. But a TikTok comment funnel is not the right way to address them.

Anastrozole is one of the most over-prescribed drugs in men's health. A 2019 commentary in the Journal of Clinical Endocrinology and Metabolism flagged that many TRT clinics prescribe AIs prophylactically rather than based on symptoms or labs. If your clinic gave you anastrozole without checking your estradiol first, that's worth questioning.

Fasting insulin testing is genuinely underused in standard TRT monitoring panels. SHBG, fasting glucose, and HbA1c are more commonly ordered, but fasting insulin gives a more sensitive picture of insulin resistance. Asking your provider to add it to your next panel is reasonable and costs almost nothing.

What Smith is selling may or may not be useful. What he's describing as the problem, fragmented TRT management with no lifestyle integration, is a real and documented gap in how many clinics operate. That doesn't make his DM funnel the solution, but it does mean the underlying frustration he's targeting is legitimate.