Antioxidant plant compounds from green tea. Controlled trials support small, reliable improvements in blood pressure and cholesterol; population studies link habitual tea drinking with lower heart-disease and overall death rates. A low-cost, modest-benefit addition whose value depends on choosing a sensible form and keeping the dose within safe limits. (Full Review)
| Marker | Target | Why |
|---|---|---|
| ALT (alanine aminotransferase) | < 25 U/L (men), < 20 U/L (women) | Detects early liver stress from concentrated extracts |
| AST (aspartate aminotransferase) | < 25 U/L | Confirms and tracks liver injury alongside ALT |
| Systolic / diastolic blood pressure | < 120 / 80 mm Hg | Primary efficacy marker for the blood-pressure benefit |
| LDL cholesterol | < 100 mg/dL (lower if high cardiovascular risk) | Tracks the lipid-lowering benefit |
| Ferritin / iron studies | Ferritin 50–150 ng/mL | Detects catechin-related iron depletion |
| Fasting glucose | 70–85 mg/dL | Tracks any metabolic benefit |
Cadence: Check liver enzymes and the targeted markers at baseline, again at 8–12 weeks after starting an extract, then every 6–12 months with continued use (or promptly if symptoms of liver trouble appear).