Evidence explainerRhodiola rosea
Rhodiola Rosea Benefits: Small, Mixed Trials and an NIH "Not Enough Evidence" Verdict
Rhodiola is marketed for energy, endurance and stress. NCCIH says the evidence is not reliable enough to say it helps; here is what the small trials found.
Key takeaways
- NCCIH says there isn't enough reliable evidence to know whether rhodiola is useful for any health purpose [1].
- A review of 13 small trials (263 people) found a single amount before exercise improved endurance and perceived exertion, but most trials had unclear or high risk of bias [2].
- In 48 marathon runners, 600 mg/day for 30 days did not change race time, soreness or muscle-damage markers [3].
- In 60 adults with stress-related fatigue, 576 mg/day of an extract beat placebo on a burnout scale and attention measures over 28 days [4].
- A 14-day trial in 80 mildly anxious adults found lower self-reported stress, but it had no placebo group [5].
The evidence, graded
Pulled from our monograph evidence tables. Grades follow our evidence-grading policy.
- Grade CMixedExercise performanceResults were heterogeneous: 11 studies found some positive effects and 2 found none. A single amount before exercise improved endurance and perceived exertion; longer use improved anaerobic but not endurance performance.
- Grade CNo effectMuscle damage, soreness and inflammation after a marathonNo difference from placebo in race time, loss of jump height, muscle soreness, muscle-damage markers, cytokines or heat shock protein 72.
- Grade DImprovedFatigue and attention scoresBoth groups improved (placebo effect), but SHR-5 beat placebo on a burnout scale and several attention measures and changed the cortisol response to waking. No serious side effects attributed to the extract were reported.
The agency view
NCCIH says there isn't enough reliable evidence to determine whether rhodiola is useful for any health-related purpose, and that most human research is of low-to-moderate quality [1].
Exercise
A 2023 systematic review of 13 trials (263 healthy people aged 18 to 65) found heterogeneous results: 11 studies had some positive effects and 2 had none [2]. A single amount before exercise improved endurance and perceived exertion, while longer use helped anaerobic but not endurance performance [2].
In a 30-day trial, 48 experienced marathon runners took 600 mg/day or placebo; race times, loss of jump height, soreness and muscle-damage markers did not differ [3].
Fatigue and stress
In a 28-day trial of 60 adults aged 20 to 55 who met Swedish criteria for stress-related fatigue, both groups improved, but the SHR-5 extract (576 mg/day) beat placebo on a burnout scale and several attention measures [4].
In 80 mildly anxious adults, 400 mg/day for 14 days lowered self-reported anxiety and stress versus no treatment; without a placebo group, the authors say a causal link cannot be determined [5].
Before trying it
NCCIH calls rhodiola possibly safe for up to 12 weeks, and interactions with the blood-pressure drug losartan have been reported [1]. See rhodiola side effects and interactions.
Quick answers
Does rhodiola lower cortisol?
In the 28-day fatigue trial, the cortisol response to waking changed in the extract group compared with placebo [4]. That is one small trial.
How much rhodiola was used in trials?
Trials used 400 to 600 mg/day of extract, and single amounts before exercise [5][3][2].
Does rhodiola help with sleep?
None of the trials in our sources measured sleep, and NCCIH lists insomnia as a possible side effect [1].
Keep reading
Full monographs
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Browse the full Supplement & Nutrient Encyclopedia or all supplement articles.
References
- [1]Rhodiola (last updated April 2025). National Center for Complementary and Integrative Health, 2025.
- [2]Rhodiola rosea supplementation on sports performance: A systematic review of randomized controlled trials. Phytother Res, 2023.
- [3]Evaluation of Rhodiola rosea supplementation on skeletal muscle damage and inflammation in runners following a competitive marathon. Brain Behav Immun, 2014.
- [4]A randomised, double-blind, placebo-controlled, parallel-group study of the standardised extract shr-5 of the roots of Rhodiola rosea in the treatment of subjects with stress-related fatigue. Planta Med, 2009.
- [5]The Effects of Rhodiola rosea L. Extract on Anxiety, Stress, Cognition and Other Mood Symptoms. Phytother Res, 2015.