Concretely: HbA1c · oral semaglutide.
This is one of those things that everyone repeats and nobody derives.
This matters practically, not just academically, because it changes what I would do next.
Is the standard explanation correct, and if so, what is the evidence for it?
Reference intervals for alanine aminotransferase differ between laboratories and have been revised downward over time, so the same value can be normal on one report and elevated on another.
Weight loss of ten per cent or more typically reduces transaminases substantially in people whose elevation was driven by hepatic fat, which is the majority of mild elevations in this population.
| Trial | Agent | n | Duration | Primary result |
|---|---|---|---|---|
| STEP 1 | Semaglutide 2.4 mg | 1,961 | 68 wk | −14.9 % vs −2.4 % weight |
| STEP 2 | Semaglutide 2.4 mg, T2DM | 1,210 | 68 wk | −9.6 % vs −3.4 % weight |
| SURMOUNT-1 | Tirzepatide 5/10/15 mg | 2,539 | 72 wk | −15 / −19 / −21 % weight |
| SURMOUNT-4 | Tirzepatide, withdrawal | 670 | 88 wk | Continued loss vs substantial regain |
| SELECT | Semaglutide 2.4 mg | 17,604 | ~40 mo | MACE HR 0.80 (0.72–0.90) |
| FLOW | Semaglutide 1.0 mg, CKD | 3,533 | ~3.4 yr | Renal composite reduced; stopped early |
| SURMOUNT-OSA | Tirzepatide, OSA | 469 | 52 wk | AHI reduced with and without PAP |
Creatine kinase, alkaline phosphatase and bilirubin together tell you which compartment the abnormality is in, and ordering the transaminases alone throws that information away.
Laboratory-specific reference intervals for transaminases vary enough that cross-laboratory comparison of borderline values is unreliable.
Nothing here is medical advice. An abnormal result needs somebody who can take a history and examine you.
Transaminases plus bilirubin plus alkaline phosphatase, or you have not measured enough to conclude anything.
Aggregated, published test results and vendor ratings built from submitted batches. Methodology stated, dataset browsable, no listing fees.
Browse resultsBefore attributing anything to a compound, account for alcohol, muscle injury from new training, and any over-the-counter product being taken alongside.
Hy's law describes the combination that matters: transaminases above three times the upper limit together with bilirubin above twice the upper limit and no cholestatic explanation. That combination is a signal; isolated mild transaminase elevation is not.
An isolated result three weeks after starting anything is difficult to interpret. A baseline taken before starting makes the same result trivially interpretable, which is the argument for baselines.
Research-use material of unknown content is an unquantifiable variable in any such attribution.
New training, alcohol and over-the-counter products first. Then the interesting hypotheses.
Start with the pattern. A hepatocellular pattern with alanine aminotransferase above aspartate aminotransferase points one way; a cholestatic pattern with alkaline phosphatase and gamma-glutamyl transferase points another.
Gamma-glutamyl transferase is sensitive and unspecific: it rises with alcohol, with several medications and with fatty liver, and an isolated elevation rarely changes anything on its own.
Very rapid weight loss can transiently worsen liver biochemistry, which is one of several arguments against pursuing the steepest possible trajectory.
Hy's law and its variants are the standard framework for identifying drug-induced liver injury in trials and are why bilirubin is measured alongside transaminases rather than instead.
Read the pattern before the magnitude, and the magnitude in multiples of the upper limit.
The honest answer is that mild elevation is very common, that it usually improves with weight loss, and that the exceptions are the reason anyone checks.
Reference upper limits around forty units per litre for ALT are conventional rather than physiological; several groups have argued for limits closer to thirty for men and twenty-five for women.
Attributing an enzyme change to a compound requires a baseline, and most people asking have not got one.
Isolated mild elevation is common and usually improves with weight loss.
edited 27 Jun 2025 by plate_count_9k — added the method parameters
Answering this needs the magnitude in multiples of the upper reference limit, because the thresholds that matter clinically are defined that way and not in absolute units.
Alanine aminotransferase is relatively liver-specific; aspartate aminotransferase is also present in muscle, heart and red cells. A raised AST with a normal ALT after heavy resistance training is usually muscle, and creatine kinase settles the question.
Trials in this class have generally reported improvement rather than deterioration in liver biochemistry, consistent with the weight-mediated mechanism.
Get a baseline before you start anything, because it converts an uninterpretable result into an interpretable one for the cost of one blood draw.
Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.