Rhodiola rosea is a short-acting root extract used as a fatigue and stress tonic. The clearest human signal is modest easing of stress-related tiredness and a small improvement in endurance and perceived effort, mainly with standardized extracts taken in the morning or before work. Evidence is mixed. Retail extracts often fail authenticity tests. Not a proven lifespan intervention. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Morning serum or salivary cortisol | Track change from own baseline; clear awakening rise that settles by afternoon | Can flatten an exaggerated cortisol awakening response |
| Fasting plasma glucose | 70–85 mg/dL | Animal and precautionary notes on glucose lowering |
| Resting blood pressure | <120/80 mmHg | Occasional pressure-lowering and stimulatory pulse reports |
| INR (if on warfarin) | Prescriber’s target, often 2.0–3.0 | Documents the 21% CYP2C9 shift |
| Body weight / waist | Individual baseline | Indirect check if appetite or training volume changes |
Cadence: 1 week (sleep, restlessness, blood pressure); 4 weeks (fatigue or training logs, repeat glucose and pressure); every 3–6 months if use continues; drug-level recheck 3–7 days after start or stop on CYP2C9 substrates