Three essential protein building blocks sold mainly as a training supplement. In liver disease, studies show less confusion from liver failure and better nutritional markers, though not longer survival. In healthy, well-fed training adults only soreness falls; no strength or muscle-size effect is established. Higher blood levels travel with later metabolic and heart disease. Stomach upset is the main complaint. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Fasting insulin | 2–5 µIU/mL | Earliest signal of impaired clearance capacity |
| HOMA-IR | Below 1.5 | Combines fasting glucose and insulin into one insulin-resistance index |
| HbA1c | 4.8–5.4% | Confirms whether the metabolic association applies to this individual |
| Fasting plasma branched-chain amino acids | 350–450 µmol/L combined | Direct measure of whether levels are accumulating on the current dose |
| Plasma ammonia | 15–35 µmol/L | Detects the nitrogen load that defines the upper intake limit |
| Alanine aminotransferase | 10–26 U/L | Liver enzyme; screens the organ handling the nitrogen surplus |
| Blood urea nitrogen | 10–16 mg/dL | Reflects protein load and nitrogen clearance together |
| Estimated glomerular filtration rate | Above 90 mL/min/1.73 m² | Determines whether nitrogen clearance is adequate |
| Creatine kinase | 40–200 U/L | Tracks muscle damage, the outcome soreness benefits are meant to reflect |
| Appendicular lean mass index | Above 7.0 kg/m² (men), 5.5 kg/m² (women) | The outcome that matters if the goal is muscle preservation |
Cadence: Baseline panel before starting; metabolic markers repeated at 12 weeks, then every 6 to 12 months while use continues; body composition annually; ammonia added at 12 weeks at the higher clinical doses.