Supplement
Rhodiola Rosea
Fatigue under stress, on four small short trials of one proprietary extract, each with an author linked to its maker, against one independent registered trial in which fatigue was worse on Rhodiola than on placebo An inactive substitute made to look like the real treatment, so participants cannot tell which one they received..
Grade C: human trials exist, but they are small, mixed or not yet repeated. This is not a finding that it does not work. How to read a grade →
Rhodiola is a plant from cold mountain regions, sold for stress and tiredness. Four small, short studies of one brand found less fatigue under stress. Each of those studies had an author tied to the company that makes it. In the one outside study, people taking rhodiola felt more tired than people taking a dummy pill. So the results point in different directions.
A letter describes the human evidence, not the product, the manufacturer, or the ingredient's worth.
See the full evidence record →Who responds: this record's trial reading reports no subgroup that identifies who responds.
Investigators: All four trials this Grade C rests on were run by investigators employed by, founded by, or belonging to the organization that developed, sells or teaches the intervention (the institute that developed and sells the extract tested, with its scientists among the authors). The funder may read non-commercial; the people who ran the trials are part of the organization whose intervention they tested, which is stated here so it can be weighed alongside the letter.
Fatigue under stress on four small trials of one maker-linked extract, with the one independent trial finding fatigue worse than placebo.
How this letter has changed · latest: October 2026 · Corrected
The record cited four small trials of one proprietary extract, each with a maker-linked author, and omitted the only fully independent registered trial (Punja et al., PLoS One, 2014; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 25268730), in which fatigue was significantly worse on Rhodiola than on placebo. Added with it: the systematic reviews rating every trial at high or unclear risk of bias (Ishaque et al., 2012; PMID 22643043) and noting no independent replication The same finding reproduced by a separate research group. A result seen once can be chance or bias; a replicated one is harder to explain away. (Hung et al., 2011; PMID 21036578). The best-use line's anti-aging effects via AMPK, measured in no human trial, and the 200 to 600 mg/day range, which the trials do not support, are removed. Mixed evidence stays C. Applied the written grade definition under the editor's standing instruction of October 2026 (Arnold Sandlow, D.C.).PMID 21036578 PMID 22643043 PMID 25268730
Ties stated beside the letter. All four trials, Shevtsov 2003 (PMID 12725561), Darbinyan 2000 (PMID 11081987), Spasov 2000 (PMID 10839209) and Olsson 2009 (PMID 19016404), tested one proprietary standardized extract, and each has a scientist from the institute that developed and sells it among its authors; none names a funder. Letter unchanged.PMID 12725561 PMID 11081987 PMID 10839209 PMID 19016404
Every change to a letter on this site is dated and published. The full evidence log →
Commercial disclosure
EBL earns no commission on any supplement it grades. A purchase made through the dispensary link below pays EBL nothing, the practitioner discount goes to you in full. The dispensary is Fullscript, a practitioner dispensary, and many of the professional-grade brands in it are sold mainly through practitioners rather than in health food stores. Grades are assigned by published rubric before any commercial relationship exists and are never influenced by one. Full disclosure.
Grade C reflects limited, mixed, or single-trial human data not yet independently replicated. The biological rationale may be strong. The human evidence does not currently meet the bar for Grade B. EBL re-grades when new RCT Randomized controlled trial: people are assigned to the treatment or a comparison by chance, so the groups differ only in what they received. It is the design that can show cause and effect. evidence is published.
The cited trials used one proprietary standardized extract; only Olsson 2009 (PMID 19016404) states a daily dose in its abstract (576 mg/day), and Shevtsov 2003 (PMID 12725561) tested a single dose, not daily use. The independent trial (PMID 25268730) gave 364 mg once or twice daily.
The cited trials used a standardized Rhodiola rosea extract; results are specific to the extract each study named.
The cited trials gave a standardized extract daily (PMID 12725561, PMID 11081987, PMID 10839209, PMID 19016404). They do not state a time of day or whether doses were taken with food.
Checked against the published summaries; the full papers could not be read. What the cited trials did, not a schedule. Every supplement, by trial timing →
How to buy this: quality criteria, not a brand
200–600mg/day standardized extract (3% rosavins, 1% salidroside). Usually taken in the morning.
A standardized Rhodiola rosea root extract, as in the trials, with its rosavin and salidroside content stated.
The rosavin and salidroside percentages stated on the label.
Unstandardized root powder; no rosavin/salidroside %; late-day dosing (insomnia).
The grade and these criteria are set only from human trials. Any purchase link is convenience and does not affect the grade.
Bipolar disorder and manic states, on the activating effect. Pregnancy. Insomnia and irritability are the common dose-related effects.
CYP3A4 and P-glycoprotein inhibition has been reported, so narrow-window drugs cleared by those routes may reach higher levels. Antidepressants, particularly SSRIs and MAOIs: rhodiola is monoamine-active, so additive serotonergic effect is plausible and unmeasured. Diabetes medication and antihypertensives: additive lowering has been reported. These are mechanistic cautions.
Nothing has been co-administered, and there is one adverse case worth knowing. The serotonergic caution on rhodiola is mechanism. No trial has given rhodiola with an SSRI or an MAOI and reported what happened, and the CYP3A4 and P-glycoprotein findings behind the narrow-window caution are laboratory work rather than human dosing studies. Two published records are worth naming even though neither is a trial: a 2022 case report of mania associated with rhodiola, and a 2024 letter on potential rhodiola herb-drug interactions in perioperative medicine. A single case and a letter do not establish an interaction, and they are not nothing either, which is why they are recorded here rather than promoted into the claim. Basis: pharmacological mechanism, not a human study. Searched PubMed in August 2026: 1 query, 26 human results.
The trials measured fatigue with timed cognitive test batteries and questionnaires over 2 to 6 weeks; the independent trial used a vitality scale and a visual analog fatigue scale. No AMPK or aging marker has been measured in a human trial.
Primary evidenceSeven papers, each linked to its PubMed record.
Shevtsov et al. (Phytomedicine, 2003; PMID 12725561), Darbinyan et al. (2000; PMID 11081987), Spasov et al. (2000; PMID 10839209) and Olsson et al. (Planta Med, 2009; PMID 19016404): randomized trials of Rhodiola rosea for stress and fatigue. Grade C (small trials, self-reported endpoints The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score.). Funding: all four trials tested one proprietary standardized extract, and each has a scientist from the institute that developed and sells it among its authors (G. Wikman on the 2000 and 2003 trials, A. Panossian on the 2000 and 2009 trials); none states a funder in its indexed record. Independent evidence: Punja et al. (PLoS One, 2014; PMID 25268730), registered double-blind Neither the participants nor the people assessing them know who received the real treatment until the trial ends. placebo-controlled trial in 48 nursing students on shift work, 364 mg once or twice daily for 42 days; fatigue was significantly worse on Rhodiola than on placebo on both the primary vitality scale and the cross-validating visual analog scale, with adverse events similar. Ishaque et al. (BMC Complement Altern Med, 2012; PMID 22643043): systematic review of 11 trials, evidence contradictory, every trial at high or unclear risk of bias. Hung et al. (Phytomedicine, 2011; PMID 21036578): systematic review of 11 placebo-controlled trials, noting the lack of independent replication. The outcomes in the positive trials were mostly timed test batteries (fatigue indices) with questionnaires, not self-report alone. Mixed, low-quality evidence with one independent trial finding harm: C.
Educational use only · Not medical advice · Starting, stopping or changing any supplement or medication is a decision for your physician
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. The grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
This page carries a letter. EBL takes no commission, referral fee or payment of any kind on anything it grades. No letter has been bought and none is for sale.
How this is enforced
That is not a promise, it is a build condition. Two checks run on every deploy: one refuses to publish if a commission is claimed on anything graded, the other refuses if a page names a commercial relationship that is not declared in the register. If either fails, this page does not go live. You can read how the checks work, and what they do not cover, on the evidence integrity page.
Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →