Last updated: October 2026
Ashwagandha is more often used for feeling stressed and wired, rhodiola for feeling stressed and exhausted. Ashwagandha has more trials for stress, though the evidence is low certainty, while reviews of rhodiola call its results contradictory. In the UK, rhodiola is sold as a registered traditional herbal medicine for stress symptoms, and ashwagandha is under FSA safety review.
Below: a side-by-side comparison, what the research shows for each, UK status, safety, and how to choose.
Ashwagandha vs rhodiola at a glance
| Ashwagandha | Rhodiola | |
|---|---|---|
| Plant | Withania somnifera root, from India | Rhodiola rosea root, from cold mountain regions |
| Typical use | Feeling stressed, tense, sleeping poorly | Feeling stressed, tired and run down |
| Feel | Calming for many people | Can feel mildly stimulating |
| Best time | Often evening | Morning or early afternoon |
| Evidence | 12 trials on stress and anxiety, low certainty | Small trials; reviews call results contradictory |
| UK status | Food supplement; under FSA safety review | Registered traditional herbal medicine for stress symptoms |
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View productAshwagandha: what the research shows
A 2022 review of 12 trials with about 1,000 people found ashwagandha lowered stress and anxiety scores compared with placebo, most clearly at 300 to 600mg a day, but rated the certainty as low. A 2021 review found a small improvement in sleep. See what ashwagandha does and when to take it.
Rhodiola: what the research shows
A 2011 review of 11 placebo-controlled trials suggested rhodiola may help physical and mental performance and some mood measures. A 2012 review of 11 trials on fatigue concluded the research was contradictory, with many studies of poor quality. Most trials used standardised root extracts at a few hundred milligrams a day.
UK status
- Rhodiola: some products hold a Traditional Herbal Registration from the MHRA for temporary relief of stress symptoms such as fatigue, exhaustion and mild anxiety. That’s based on traditional use, not proof from trials, but it does mean set quality standards and a patient leaflet.
- Ashwagandha: sold as a food supplement. The FSA’s toxicity committee is reviewing reports of liver, thyroid and blood sugar effects, with no outcome yet. Read our ashwagandha UK safety review.
See also reishi vs ashwagandha.
Safety and who should avoid them
| Ashwagandha | Rhodiola | |
|---|---|---|
| Common side effects | Stomach upset, drowsiness | Dizziness, dry mouth, restlessness, poor sleep if taken late |
| Avoid if | Pregnant or breastfeeding, under 18, liver or thyroid problems | Pregnant or breastfeeding, under 18, bipolar disorder |
| Check medicines | Thyroid, diabetes, blood pressure, sedatives, immune-suppressants | Antidepressants, diabetes and blood pressure medicines |
Don’t take either alongside prescribed treatment for anxiety or depression without asking your GP. We don’t recommend our products during pregnancy or breastfeeding.
Which should you choose?
- Wired and can’t switch off in the evening? Ashwagandha is more commonly used, if you’re not in a group that should avoid it.
- Drained and flat during the day? Rhodiola, taken in the morning, is the traditional choice.
- Want the most cautious option? Magnesium has authorised claims for tiredness and psychological function. See ashwagandha vs magnesium.
Our Flow CBD Oil combines broad spectrum CBD with ashwagandha root and maca for daytime use. The FSA’s 10mg a day figure for CBD is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication. See also natural supplements for anxiety.
Related guides
- Holy basil vs ashwagandha.
- For the anxiety trials in detail, see ashwagandha for anxiety: what the research shows.
- See also our full guide to rhodiola rosea benefits, side effects and dose.
- How ginseng compares with ashwagandha and rhodiola.
- If sleep is your main reason for looking, see ashwagandha for sleep.
- The reishi mushroom, another popular adaptogen.
- Before choosing, read our guide to ashwagandha side effects, including the rare liver and thyroid risks.
- For the ashwagandha timeline, see how long ashwagandha takes to work.
Sources 4
- Akhgarjand C et al. Does ashwagandha supplementation have a beneficial effect on anxiety and stress? A systematic review and meta-analysis. Phytother Res, 2022.
- Hung SK et al. The effectiveness and efficacy of Rhodiola rosea L.: a systematic review of randomized clinical trials. Phytomedicine, 2011.
- Ishaque S et al. Rhodiola rosea for physical and mental fatigue: a systematic review. BMC Complement Altern Med, 2012.
- FSA. Summary of responses to call for evidence on ashwagandha, 2026.
