One plant sold as three products. Root is used for urinary difficulty in older men; leaf for hay-fever symptoms and blood sugar; the fresh plant stings. Best-supported is a modest drop in fasting blood sugar in type 2 diabetes. The marketed testosterone claim has never been tested in people. A small, cheap, low-risk nudge rather than a decisive lever. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Fasting glucose | 75–85 mg/dL | Primary benefit endpoint and hypoglycaemia guard |
| HbA1c | Below 5.4% | Confirms the fasting change is sustained, not transient |
| High-sensitivity C-reactive protein | Below 0.5 mg/L | Tracks the pooled inflammation benefit |
| Triglycerides | Below 80 mg/dL | Second pooled metabolic endpoint |
| Seated and standing blood pressure | 110–120 / 70–80 mmHg | Detects additive hypotension with drugs or supplements |
| Potassium and creatinine with eGFR | Potassium 4.0–4.5 mmol/L; eGFR above 90 mL/min/1.73 m² | Guards the diuretic effect, especially with loop diuretics |
| Prostate-specific antigen | Below 1.0 ng/mL under age 60; below 2.0 above | Confirms nettle is not masking a rising value |
| Total testosterone and sex hormone-binding globulin | Testosterone 600–900 ng/dL; SHBG 20–40 nmol/L | Tests the hormonal claim directly rather than assuming it |
| Alanine aminotransferase | Below 25 U/L in men, below 20 U/L in women | Baseline liver safety, since one trial reported this enzyme falling |
| International normalised ratio | Individual anticoagulation target | Detects vitamin K interference from leaf intake |
Cadence: Glucose and standing blood pressure at 2 and 4 weeks, then the full panel at 12 weeks, then every 6 to 12 months on continued use. Men repeat the urinary symptom score at 12 and 24 weeks.