Inexpensive oral supplement, long safety record. Joint trials split along funding lines; large population studies link regular use to lower death rates and fewer chronic diseases, but these are associations, and survival has never been measured in a controlled trial. Side effects are mild, with narrower concerns for eye pressure, clot-preventing medication, blood sugar, and established Alzheimer's disease. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Fasting glucose | 75–86 mg/dL | Detects the dose-dependent insulin-sensitivity risk |
| HbA1c | 4.8–5.3% | Confirms whether any glucose change is sustained rather than a single-day artefact |
| Fasting insulin | 2–5 µIU/mL | Insulin rises before glucose does, so it detects the metabolic signal earliest |
| High-sensitivity C-reactive protein | < 0.9 mg/L | Identifies the elevated-inflammation subgroup where the metabolic and vascular associations concentrate |
| Intraocular pressure | 10–18 mmHg | The one risk with a genuine organ-damage endpoint |
| Alanine aminotransferase | 10–26 U/L (men), 8–22 U/L (women) | Detects the hepatotoxicity signal seen in people with existing liver disease |
| International normalized ratio | Individual target, commonly 2.0–3.0 | The single interaction with documented serious harm |
| Estimated glomerular filtration rate | > 90 mL/min/1.73 m² | Establishes renal baseline before long-term daily use |
| Kellgren-Lawrence grade | No established target; track change from the individual's own baseline radiograph | Defines whether structural benefit is even plausible |
Cadence: Fasting glucose and HbA1c at baseline and 12 weeks, then every 6 to 12 months. Tonometry at baseline and annually, or at 3 months and then annually if baseline pressure exceeded 18 mmHg. Liver enzymes at baseline and 8 to 12 weeks in existing liver disease. International normalized ratio at 1, 2 and 4 weeks after starting for anyone anticoagulated, then back to their usual schedule.