Black currant is a food first, supplement second. Most consistent: about a week of concentrated extract shifts exercise fuel use toward fat. Whether that improves performance is less settled. Artery widening after a fatty meal is reasonably supported; blood pressure benefit has not held up. Acidic drinks wear tooth enamel; seed oil loosens stools and can add to blood-thinner effects. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Seated resting blood pressure | 105–120 / 65–80 mmHg | Detects the vasodilatory effect and any additive drop with medication |
| hs-CRP | < 1.0 mg/L | Tracks whether the anti-inflammatory signal seen in recovery trials translates systemically |
| Fasting glucose | 75–90 mg/dL (4.2–5.0 mmol/L) | Baseline for the post-meal glycaemic effect of whole berry |
| Fasting insulin | 2–5 µIU/mL | More sensitive than glucose to the early insulin-blunting effect |
| HbA1c | 4.8–5.3% | Confirms whether repeated post-meal blunting accumulates into a real change |
| INR (anticoagulant users only) | Target set for the indication, commonly 2.0–3.0 | Detects additive anticoagulant effect from seed oil |
| Intraocular pressure (glaucoma only) | 10–18 mmHg | The one ocular outcome with human data behind it |
| Serum P1NP | No established target; change from own baseline | The marker that moved in the bone trials, and the earliest signal of a bone effect |
| DXA bone mineral density T-score | ≥ −1.0 | The outcome that matters; the marker above is only a proxy for it |
| Respiratory exchange ratio at a fixed workload | No established target; change from own baseline | Directly measures the best-supported effect of the extract |
Cadence: Baseline before the first dose; blood pressure at 1 and 4 weeks, then every 6 months; metabolic and inflammatory markers at 3 months, then every 6–12 months; clotting time rechecked 2 weeks after any change in seed oil dose; bone density no sooner than 24 months.