Rhodiola rosea is a plant used in supplements for stress, fatigue, mood, thinking, and exercise. Human studies have reported some encouraging results, especially in short studies of stress-related symptoms and exercise, but the findings are mixed and the U.S. National Center for Complementary and Integrative Health says there is not enough reliable evidence to determine whether it is useful for any health-related purpose.
That means it is reasonable to be interested in rhodiola, but the study details matter: researchers have used different extracts, doses, groups of people, and outcomes. The useful question is not simply whether rhodiola “works,” but what was studied, for whom, and for how long.
Quick facts on Rhodiola rosea
| Question | What the studies and official guidance say |
|---|---|
| Forms studied | Rhodiola rosea extracts and rhodiola preparations; studies do not make all extract products interchangeable. |
| Doses used in randomized trials | 290 to 1,500 mg daily in the 2026 systematic review. |
| Typical study length | 3 to 16 weeks in that review; NCCIH describes rhodiola as possibly safe for up to 12 weeks. |
| Main uses studied | Stress-related symptoms, anxiety, depressive symptoms, sleep quality, cognitive function, exercise performance, strength, and recovery. |
| Overall certainty | Mixed and limited. Many studies are small, short, or at risk of bias. |
What do human studies show?
Stress, anxiety, mood, and sleep
A 2026 systematic review included 24 randomized controlled trials of ashwagandha and rhodiola; five were rhodiola studies. A randomized controlled trial is a study that assigns people to an intervention or comparison group. Across the included trials, participants were 18 to 75 years old, and the rhodiola studies used 290 to 1,500 mg daily for 3 to 16 weeks. The review reported improvements in stress, anxiety, depressive symptoms, sleep quality, and cognitive outcomes, but also flagged short study periods, small samples, and major differences between studies.
For depression specifically, a 2016 review described two randomized, double-blind, placebo-controlled trials totaling 146 adults with major depressive disorder, plus seven open-label studies totaling 714 people with stress-induced mild depression. It found a possible antidepressant effect, not a settled answer. An open-label study means participants and researchers know what is being taken, so expectations can affect results.
The comparison people often make is rhodiola versus ashwagandha for cortisol, a hormone involved in the body’s stress response. The 2026 review examined both plants, but it included 19 ashwagandha studies and only five rhodiola studies. It does not provide a head-to-head answer that one is better for cortisol. It also grouped several outcomes together, so it cannot tell you that either ingredient will change your own cortisol level.
Fatigue, concentration, and mental performance
A 2010 review reported that repeated use of one rhodiola extract, SHR-5, was associated with anti-fatigue effects, concentration in healthy people, and less burnout in people with fatigue syndrome. This older review also discusses laboratory and animal findings, which are useful for generating ideas but are not the same as results in people.
A different 2009 review reached a more cautious conclusion. Its authors found important statistical and reporting problems in most studies claiming improvement, noted higher-quality studies with no significant effect, and concluded that the available evidence was insufficient. This conflict is why a positive result from one small trial should not be read as a promise of better focus or energy.
If you want a clearer way to judge what a trial result means, see systematic reviews and meta-analyses. A review can be useful, but its conclusion is only as dependable as the trials it includes.
Exercise performance and recovery
A 2023 systematic review of randomized trials included 13 studies with 263 healthy participants, ages 18 to 65. Eleven studies reported some positive result and two found no effect on measures such as perceived exertion, heart rate, antioxidant capacity, blood lactate, creatine kinase, or C-reactive protein.
The authors reported that acute, or short-term, rhodiola use had positive findings for endurance performance and perceived exertion. Chronic use had positive findings for anaerobic exercise performance, but not endurance performance, and may have affected muscle-damage measures. Most studies had unclear or high risk of bias, and the exercise and supplement protocols differed. In plain terms: there are signals worth studying, but not a dependable result for every workout or athlete.
Heart-related symptoms
A 2014 systematic review assessed seven randomized trials involving 662 people with chronic stable angina. Some trials added oral or intravenous rhodiola to conventional treatment and reported symptom-related improvements. Oral rhodiola did not improve the electrocardiogram outcome in the review.
The review says all included studies were published in Chinese and lacked high-quality scientific design; samples were small and intervention periods short. Keep prescribed heart medicines and routine medical care in place unless the clinician managing them advises otherwise.
What doses did researchers use?
Researchers in the 2026 review used 290 to 1,500 mg of rhodiola daily for 3 to 16 weeks. Those numbers describe study protocols, not a personal dose or a reason to take it every day. The studies used standardized extracts and preparations that may differ from the ingredient, amount, and directions on a supplement label.
The National Center for Complementary and Integrative Health says rhodiola is possibly safe for up to 12 weeks. Longer-term use is still unclear. If you are weighing a study result, separate the dose from the outcome: a study dose is meaningful only alongside its extract, participants, duration, comparison group, and measured result. Surrogate outcomes in trials explains why a change in a lab number does not always mean a change a person can feel.
What are the side effects and medicine interactions?
NCCIH lists dizziness, headache, insomnia, dry mouth, and excessive saliva production as possible side effects. NCCIH also says interactions between rhodiola and losartan, a medicine used for high blood pressure, have been reported.
The same official page says that if you take any medicine, discuss an herbal product with your health care provider before using it because herbs and medicines can interact in harmful ways. This is especially important if you take losartan or another prescription medicine. NCCIH also notes that dietary supplements are not approved by the FDA before sale; manufacturers and distributors are responsible for evaluating safety and labeling before marketing.
NCCIH does not list liver or kidney injury among rhodiola’s possible side effects. If you have liver or kidney disease, ask the clinician managing that condition before considering it.
Who should talk to a clinician first?
Talk to a clinician first if you are pregnant, breastfeeding, take losartan, take any other medicine, or have liver or kidney disease. NCCIH says little is known about rhodiola’s safety during pregnancy or breastfeeding and advises people who use medicines to discuss herbal products with a health care provider.
Depression can be serious. NCCIH specifically advises people who may have depression to consult a health care provider. Rhodiola study findings should not be used to start, stop, or change a prescribed medicine.
What is still unknown?
Long-term daily use is still unclear. NCCIH’s possible-safety statement reaches up to 12 weeks, while the 2026 review covered studies lasting 3 to 16 weeks. The research also does not settle how quickly rhodiola may be felt, whether it affects belly fat, whether it is safe in liver or kidney disease, or whether it is better than ashwagandha for cortisol.
There is no clear human evidence in this collection that rhodiola changes belly fat. The exercise review focused on performance and recovery measures, not belly-fat outcomes. Better, longer trials using clearly described extracts and outcomes that matter to participants would help answer these questions.
How should you read a rhodiola label?
Start with the exact amount per serving and the form named on the label. The studies summarized here used rhodiola extracts or preparations, and results from one extract cannot automatically be carried over to another form.
| Label item | Why it matters |
|---|---|
| Amount per serving | Compare the stated amount with the 290 to 1,500 mg daily range used in the 2026 review, while remembering that a study amount is not a recommendation. |
| Form or extract | Human studies used extracts and preparations. A label should make clear what form it contains. |
| Proprietary blend | A blend can make it harder to tell how much rhodiola you receive. Ask the manufacturer for the amount before ordering if it is not stated. |
| Directions and other ingredients | These affect how the product is used and whether it fits alongside medicines or other supplements. |
Rhodiola is often described as an adaptogen, meaning a plant substance promoted for resilience to physical or psychological stress. That label describes an idea, not a guaranteed outcome. The most useful label is one that tells you the form and amount plainly, so you can compare it with the human research rather than relying on a broad promise.
By ClinicalStudyConnect.com Research Desk
This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.