I was on a roll with testosterone and kidneys, so let’s move to the liver.
There’s a long-standing myth that TRT is bad for the liver. Like most myths in our field, it started with a kernel of truth that spiraled into decades of bad dogma.
Here’s the real story.
The History of Oral Testosterone
Back in the 1940s, an oral form of testosterone was developed called methyltestosterone.
To survive first-pass metabolism, it was chemically modified with a 17α-alkylated structure. That modification worked, but it came at a cost.
Methyltestosterone caused:
- Elevated liver enzymes
- Cholestasis (blocked bile flow)
- Peliosis hepatis (blood-filled liver cysts)
- Hepatic adenomas and, in rare cases, hepatocellular carcinoma
By the 1990s, it was basically abandoned. It technically still exists in the U.S., but no provider in their right mind prescribes it today.
Unfortunately, this created a stigma: the idea that all testosterone therapy damages the liver.
The Modern Truth About TRT and the Liver
That stigma is flat-out wrong.
- Oral bioidentical testosterone does not cause liver toxicity.
- This is not the same as newer oral products like Jatenzo or Kyzatrex, which bypass the liver via the lymphatic system.
- There has never been evidence of liver or kidney toxicity from bioidentical testosterone.
And now, the research has flipped the conversation entirely.
TRT Improves Liver Health
A recent meta-analysis confirmed what smaller studies have been showing for years. TRT is not only safe in men with fatty liver disease — it actually helps.
Testosterone has potent pro-metabolic effects. By activating androgen receptors, it:
- Prevents visceral fat expansion
- Improves insulin and leptin sensitivity
- Limits lipogenesis in the liver and fat tissues
As Maya et al., 2025 put it:
“Testosterone exerts its antiobesity effects by activating the androgen receptor pathway, inhibiting visceral fat deposition, and reversing insulin and leptin resistance, ultimately reducing fat accumulation in the liver and adipose tissues.”
In practice, TRT lowers liver enzymes and helps reverse fatty liver progression.
Clinical Implications for Providers
Just like with kidney disease, TRT shows protective and restorative effects on liver health.
The research now suggests TRT should be considered a potential therapy for fatty liver disease.
This is a huge shift from the old “toxic to the liver” dogma — and it’s why I hammer metabolism and hormones so hard in the HRTU Master Course.
Conclusion: The Myth is Dead
Testosterone therapy does not damage the liver. In fact, it may be one of the most powerful metabolic interventions we have for men with fatty liver disease.
Providers who understand this data can treat patients more confidently and expand their role in metabolic medicine.This is exactly what we dive into in the HRTU Master Course. If you want the tools, the research, and the confidence to prescribe TRT without fear, this is where you start.
