Rhodiola rosea — intervention evidence review

Regulatory status: dietary supplement

• **Mental / stress-related fatigue** (night work, exams, “fatigue syndrome”).
• **Stress and burnout symptoms** (perceived stress, Pines/Maslach burnout scores, life-stress questionnaires).
• **Mild-to-moderate depression** (HAM-D, BDI, MADRS).
• **Exercise endurance, VO2, and muscular endurance** (time to exhaustion, time trial, VO2peak/VO2max, repeated-sprint / bench-press volume).
• **Cognition** (attention, working memory, reaction time, Stroop) — usually tested under fatigue, not as a standalone nootropic.
• **Altitude / hypoxia / acute mountain sickness** (SaO2, Lake Louise AMS).

Human evidence for *Rhodiola rosea* is real but **narrow, extract-specific, and methodologically fragile**. The only outcome with repeated placebo-controlled signals is **short-term mental fatigue under load** with **SHR-5 at roughly 170–576 mg/day** (Darbinyan 2000 period-1, Shevtsov 2003 single dose, Olsson 2009); Ishaque 2012 still judged that literature contradictory and high-bias, and the effect sizes are small (Olsson Pines −0.26 vs −0.07). **Depression:** Darbinyan 2007 (340–680 mg SHR-5) looks large and is SHI-funded with a near-inert placebo; the independent Mao 2015 RCT found rhodiola **≈ placebo** (HAM-D −5.1 vs −4.6). **Exercise:** acute 200 mg of a 3%/1% extract or ~3 mg/kg can shave a few tenths of a minute off a time trial or TTE (De Bock, Noreen); **chronic 200 mg/day was null**; Wang 2025’s small pooled VO2max ES (0.32) was **stronger above 600 mg/day**, not at 200 mg. **Cognition** is a fatigue-secondary finding, not a nootropic. **Altitude with *R. rosea* is unsupported**; *R. crenulata* AMS prevention failed in Chiu 2013.