Testosterone's real effects on your body: hype vs. evidence

What did @diagoslab actually say?

This video is not a typical TRT promo. @diagoslab describes testosterone use in surprisingly raw psychological terms, framing it as something men reach for to silence insecurity rather than treat a deficiency. He says the first injection feels like "gasoline in your fucking veins," that confidence surges, but that jealousy, aggression, sleeplessness, and paranoia follow. His closing line is the thesis: "once you feel that power, you're gonna chase it no matter what it costs." That last part is essentially describing addiction psychology, not fitness advice.

Worth noting: the hashtag "gear" is a well-understood slang term for anabolic steroids used above therapeutic doses. This video is not describing medically supervised TRT for hypogonadism. It is describing supraphysiological recreational cycling.

Does the science back this up?

More than you might expect, yes. The psychological effects he describes are not gym-bro mythology. They are documented in peer-reviewed literature, though the picture is more complicated than he presents it.

On aggression: a meta-analysis by Tricker et al. (1996, Medicine and Science in Sports and Exercise) found that supraphysiological testosterone doses did increase aggression scores in some subjects, but effect sizes were inconsistent. A more nuanced review by Pope et al. (2000, Archives of General Psychiatry) found that roughly 5 percent of men using high-dose androgens experienced severe psychiatric effects, including aggression and hypomania, while most experienced milder mood changes. So "you get mad easier" is real, but it is not universal.

On sleep disruption: testosterone at supraphysiological levels has documented effects on sleep architecture. Liu et al. (2003, Journal of Clinical Endocrinology and Metabolism) found testosterone administration suppressed REM sleep and increased sleep fragmentation. "You haven't slept in days" is an exaggeration, but the underlying mechanism is real.

On psychological dependence: Kanayama et al. (2009, Drug and Alcohol Dependence) documented that a subset of anabolic steroid users develop dependence syndromes that match DSM criteria, driven in part by body image disorders. His framing of chasing power "no matter what it costs" aligns closely with this clinical pattern.

What did they get wrong (or right)?

He got the broad strokes right but oversimplified the mechanism. The claim that "weight's absolutely fly" is accurate for lean mass accrual during a cycle, though much of early weight gain is water retention from aromatization, not muscle. That distinction matters if someone is evaluating real long-term outcomes.

His psychological framing is where he is most accurate and most nuanced. Describing testosterone use as a response to feeling "not big enough, not hard enough, not man enough" is consistent with research on muscle dysmorphia as a driver of anabolic steroid use. Olivardia et al. (2000, American Journal of Psychiatry) found elevated rates of body dysmorphic thinking among male steroid users compared to non-using gym populations.

What he gets wrong, or at least leaves out, is that these effects are strongly dose-dependent. Men on physician-supervised TRT at physiological replacement doses (bringing testosterone into the normal male range) do not typically experience the paranoia, sleeplessness, or compulsive use patterns he describes. Conflating supervised TRT with recreational high-dose cycling without making that distinction does a disservice to men who genuinely need hormone therapy.

What should you actually know?

If you are considering TRT because you have symptoms of hypogonadism, low energy, poor recovery, low libido, and a blood test showing low testosterone, the scenario this video describes is not your scenario. Supervised TRT at appropriate doses has a well-established safety profile. The psychiatric risks he describes are largely associated with supraphysiological dosing, not replacement therapy.

If you see yourself in his description of chasing testosterone to silence a voice telling you that you are not enough, that is a clinical concern worth taking seriously before any hormones are involved. The American Urological Association guidelines emphasize that testosterone is not a treatment for depression or body image disorders, and starting a cycle to fix psychological distress typically makes those issues worse, not better.

The dependence pattern he describes is real. Kanayama et al. estimated that roughly 30 percent of long-term anabolic steroid users develop dependence. Stopping after a cycle suppresses the hypothalamic-pituitary-gonadal axis, meaning natural testosterone production drops, sometimes severely, which creates a biochemical pull to continue using. That is not a motivation problem. That is physiology.

If you want to explore whether TRT is medically appropriate for you, start with a proper hormone panel, not a TikTok video, and work with a provider who will evaluate the full picture.