A caffeine-free South African herbal drink with unusual chemistry and thin human evidence. High-volume daily intake lowers markers of fat oxidation and shifts internal antioxidant balance favourably, and supplies plant compounds without caffeine or the iron-blocking effect of ordinary tea. Blood-fat, stress-hormone and heart-muscle findings rest on single small studies; the blood-sugar effect is absent in people studied. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Alanine aminotransferase (ALT) | 10–26 U/L (men), 8–22 U/L (women) | Detects the idiosyncratic liver injury seen in case reports |
| Aspartate aminotransferase (AST) | 10–26 U/L | Confirms and characterises any ALT rise |
| Gamma-glutamyl transferase (GGT) | <20 U/L (men), <15 U/L (women) | Most sensitive marker of oxidative hepatic stress |
| Low-density lipoprotein cholesterol | <100 mg/dL (2.6 mmol/L); <70 mg/dL if at high risk | The lipid fraction moved most in the human trial |
| Triglycerides | <80 mg/dL (0.9 mmol/L) | Fell roughly a quarter in the six-week trial |
| High-density lipoprotein cholesterol | >55 mg/dL (men), >65 mg/dL (women) | Rose in the human trial; completes the lipid picture |
| High-sensitivity C-reactive protein | <0.5 mg/L | Tracks the inflammatory claim, unproven in humans |
| Ferritin | 50–100 ng/mL | Confirms no cost to iron status, unlike ordinary tea |
| Glycated haemoglobin (HbA1c) | 4.8–5.3% | Tests the glucose claim, unsupported in human trials |
| Home blood pressure | <120/80 mmHg | The enzyme finding predicts a fall no trial has confirmed |
Cadence: Baseline before starting high-volume daily rooibos or any concentrated extract; liver panel repeated at 12 weeks; liver and lipid panels every six to twelve months while intake continues. With tacrolimus, warfarin, or a sulfonylurea, a drug-level, clotting-time, or glucose check two weeks after any deliberate change in intake.