The colourless compound the body makes from curcumin. It is more stable in the gut, reaches higher and steadier blood levels, and is a stronger direct antioxidant. Human evidence is two small pilot trials; longer life, lower blood pressure and better blood sugar come from animals and cell cultures. Europe's food regulator set a daily ceiling of 140 mg. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Alanine aminotransferase (ALT) | 10–26 U/L (men), 8–22 U/L (women) | Earliest signal of the liver injury documented for turmeric products |
| Aspartate aminotransferase (AST) | 10–26 U/L | Confirms whether a raised ALT is liver-specific or muscle-derived |
| High-sensitivity C-reactive protein (hs-CRP) | Below 0.5 mg/L | Main inflammatory outcome rodent work moves; the only plausible efficacy marker |
| Ferritin with transferrin saturation | Ferritin 50–125 ng/mL; saturation 25–35% | Detects the theoretical iron-binding effect before anaemia develops |
| Haemoglobin A1c with fasting glucose | A1c 5.0–5.4%; glucose 75–86 mg/dL | Tracks the glucose effect seen in diabetic rodents, if it exists in people |
| Lipid panel with apolipoprotein B | Apolipoprotein B below 80 mg/dL; triglycerides below 80 mg/dL | Tracks the lipid effect reported in diabetic rodent models |
Cadence: Liver enzymes and high-sensitivity C-reactive protein at 12 weeks, then liver enzymes, ferritin, glucose and lipids every 6–12 months while use continues. Anyone taking a narrow-margin medication adds a drug level at 4 weeks.