DOES IT WORK? Dónal Ó Mathúnalooks at Rhodiola for energy and mood enhancement.
ONE OF our readers asked us to review a herbal supplement called rhodiola. It has become popular for improving mood and helping people feel more energetic.
Rhodiola provides a good example of the challenges facing anyone trying to figure out whether a popular herbal or dietary supplement is the next great breakthrough or just the latest fad.
Rhodiola is made from the roots of Rhodiola rosea, also called roseroot or Siberian Golden Root. However, "golden root" is the common name for a few herbal remedies from unrelated plants.
Knowing the scientific name of the herb you're looking for is important to check against product labels.
The rhodiola plant is native to cold, mountainous regions such as Siberia, the Alps and the Rocky Mountains. The hardy plant has a reputation for helping people cope with living in such difficult environments. It is known as an adaptogen, like ginseng, to help people adapt to the stresses of life.
Finding evidence
Our reader gave us a webpage for the rhodiola product he had heard about. This tells you that a "growing body of research" supports its use. However, it tells you nothing about this research.
The website has a Science & Research section with 27 articles and a Key Science page with 26 articles. No mention is made of rhodiola in these articles, many of which are news items praising the products sold on the site.
In its Reference Library page, only two books are listed - both of which are written by the company's chief executives.
Instead of objective evidence to help you make an informed decision, the website declares that rhodiola is "the diamond" among "the special jewels" of herbs to help people become more "cool and collected".
It claims that many Russian athletes and cosmonauts use rhodiola, which "delivers the promise of an inner oasis of peace and energy in our hurly-burly world".
While this all sounds attractive, it doesn't say whether research supports these claims. Instead, asterisks scattered throughout are supposed to draw your attention to the fine print at the bottom of the page.
Being based in the US, this company is required to state the following: "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."
US regulations allow anyone to sell dietary supplements without testing their effectiveness or safety.
So long as they include the above statement, and adhere to it, they can market their products on US websites.
This is partly why independent studies of herbs, dietary supplements and medicines sold on the internet have repeatedly found them to be low in quality.
As a consumer, you have no way of knowing whether these products are effective, safe or even contain what they claim.
Evidence from studies
You may still be wondering if rhodiola is worth trying. Animal studies have shown that rhodiola affects brain hormones like dopamine and serotonin. These hormones play an important role in people's mood and sense of wellbeing.
Herbal textbooks refer to three or four studies in which people in stressful situations (athletes, students doing exams, nightshift workers) reported feeling less tired when taking rhodiola. However, all these studies had few participants and lasted only a few weeks.
A small number of other studies have found no benefit from rhodiola. Beneficial results were mostly found with one specific Swedish product standardised to contain 1 per cent rosavin, one of rhodiola's compounds.
Recommendations
In the few studies carried out to date, rhodiola has generally been safe. At higher doses, irritability and insomnia are common side effects. Despite its popular reputation, little research supports the use of rhodiola.
All we can say is that there is insufficient evidence to make an informed decision about its value.
However, when someone is trying to sell you inner peace and tranquillity out of a bottle, you really ought to think twice.
Dónal O'Mathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University
Readers are invited to send in suggestions for products for review. E-mail healthsupplement@irish-times.ie