Blog Post

Rhodiola Rosea: A Dietitian’s Review

Rhodiola Rosea Flower

Rhodiola Rosea has long been used in certain countries for medical purposes but has recently gained popularity in the western world.

There have been claims that it can help with a variety of conditions. It is most known for its properties as an adaptogen, which means it theoretically helps your body handle stress.

In this post, I will be going through a couple of the proposed benefits of Rhodiola and examining the evidence on the topic.

Stress

Stress

Decreasing stress and handling burnout-like symptoms is one of the most common claims for Rhodiola.

One promising study on the topic featured over 100 participants who reported stress-related burnout. They took 400mg of Rhodiola per day for 8 weeks and noticed a significant improvement in symptoms.

This is promising, but there is one major flaw – there was no control group. With anything like this, there is always the potential for the placebo effect.

Maybe Rhodiola improved symptoms, or maybe symptoms would have improved similarly in a control group. Without that research being done, it is hard to say.

There will also be a common theme throughout this article about there being a lack of good quality research on this supplement.

Depression

The current consensus on Rhodiola is that it is a promising tool that might help improve depression symptoms slightly.

One study involved 57 participants with major depressive disorder who received Rhodiola, medication (Sertraline/Zoloft) or a placebo.

This is a much stronger study design than the previous one mentioned, due to the comparison between the different options.

Rhodiola appeared to reduce symptoms more than placebo, but less than actual medication.

An argument that can be made for Rhodiola though is that it has minimal negative effects. The authors of this study noted that while it was less effective than medication, assuming other research confirms this benefit, it could have merit as an option due to having fewer adverse effects.

Anxiety

Similarly, to other areas, the research on Rhodiola and anxiety is small but promising.

One study involving 80 participants found people self-reported significantly lower levels of anxiety after 14 days of supplementation.

Another study with 10 participants reported similar positive results.

Both studies had similar issues to the other ones mentioned in that they did not have control groups or any form of placebo comparison.

Learning and Memory

Learning and Memory Flow Chart

To the best of my knowledge, there is no human research on Rhodiola and learning or memory.

This initially kind of surprised me because I have seen quite a few people talking about how it can help with that.

From one perspective, animal research on this topic is quite supportive of the idea.

A review of 36 animal studies on the topic showed significant improvements in learning and memory. This was mostly assessed through methods such as measuring the time taken to escape mazes on repeated attempts.

From another perspective though, I would encourage caution with putting too much faith into animal studies. In a LOT of areas of nutrition research, we have seen things that appear to be beneficial in animals, but not actually translate in terms of positive results in humans.

Athletic Performance

Athletic Performance - Sprinter

The results for Rhodiola and athletic performance are quite mixed.

Once again there is not much research.

One study on 10 participants compared 1500mg Rhodiola per day for 3 days to a placebo. The group taking Rhodiola also consumed 500mg prior to testing.

This testing involved tests of power (low rep bench press with 75% of max) and muscular endurance (that same weight taken to failure).

Findings from this study were that power was improved, but muscular endurance was reduced in the supplementation group.

It was double-blinded and a placebo-controlled crossover study which is typically quite strong. But considering there is only a sample size of 10, and limited other research on the topic, I would be hesitant to make an assessment on the topic based on this.

Another small study on Rhodiola found that it improved performance in a 6-mile run time trial, compared to a placebo.

But once again, I would view this more as promising, while still waiting for more research before jumping to any conclusions.

Muscle Damage/Soreness

A reduction in muscle damage and soreness is probably one of the more consistent positive findings for Rhodiola.

A systematic review on the topic found that people typically get a reduced amount of muscle damage and delayed onset muscle soreness.

There appears to be a reduction in oxidative stress too which could play a role in this.

This finding is not always found though. For example, a study involving 600mg/day of Rhodiola for 30 days prior to a marathon found no difference in muscle damage or soreness.

To support the reductions in muscle damage seen in other studies though, Rhodiola consistently seems to reduce levels of blood lactate as well as creatine kinase. Both of those things are normally associated with delayed onset muscle soreness.

Muscle Growth

Muscle Growth

To the best of my knowledge, there is no research indicating Rhodiola directly helps with muscle growth.

I can see how other people could come to the conclusion that it could indirectly help with muscle growth though.

If it consistently helped improve both stress and energy levels, you could make an argument that those things would help muscle growth indirectly.

For now, there is not really anything to indicate that it directly helps muscle growth.

Fatigue

Another area with more inconsistent evidence is the impact of Rhodiola on fatigue.

A systematic review on that topic including 11 studies covering both mental and physical fatigue.

Two of the six studies on physical fatigue found significant improvements.

Three of the five studies on mental fatigue found significant improvements.

The most promising study involved 100 subjects with chronic fatigue symptoms (not chronic fatigue syndrome) taking 400mg per day split over 2 doses. They noticed a significant change within a week and continued improvement over the following seven weeks.

Unfortunately, this study had a massive gap in that there was no placebo/control group.

One aspect the authors of the systematic review highlighted was that most of these studies had methodological flaws and risk of bias. It definitely makes sense to be cautious about making strong interpretations about the effectiveness based on this.

Dosage and How to Take

Rhodiola is typically taken in dosages of between 200mg and 600mg per day. Sometimes it is taken all at once, other times it is split up.

As you can tell from the research above, it is hit and miss in terms of effectiveness. Because of this inconsistency, it is hard to find an optimal dosing protocol.

Although the data is inconsistent, others have described it as a bell-shaped curve. While there appear to be minimal downsides of the supplement in “normal” dosages, exceeding ~680mg does not appear to provide any further benefit, so it makes sense to not go higher than that mark.

Practical Summary

Pointing out the obvious, there clearly is not enough good quality studies on Rhodiola.

This is actually one of the least practical articles I have ever written, since there is not a lot of things that can be definitively said on the topic.

Even a lot of the studies showing relatively large positive results had the clear gap of not having a placebo control group.

Personally, based on all of this, I do not view it as one of the “go-to” supplements that I would recommend to people.

From another perspective, out of a review that covered 10 studies involving 183 individuals, no adverse effects* were found. So if you wanted to take it and try it yourself, there appears to be minimal downside.

*Obviously as with every supplement, check with your doctor to see if it could have adverse effects for you specifically, or if it interacts with any medications you take.

By Aidan Muir

Aidan is a Brisbane based dietitian who prides himself on staying up-to-date with evidence-based approaches to dietetic intervention. He has long been fascinated by all things nutrition, particularly the effects of different dietary approaches on body composition and sports performance. Due to this passion, he has built up an extensive knowledge base and experience in multiple areas of nutrition and is able to help clients with a variety of conditions. One of Aidan’s main strengths is his ability to adapt plans based on the client's desires. By having such a thorough understanding of optimal nutrition for different situations he is able to develop detailed meal plans and guidance for clients that can contribute to improving the clients overall quality of life and performance. He offers services both in-person and online.