October 29, 2004 – Russian researchers argue that optimal doses of rhodiola (Rhodiola rosea) to achieve the claimed anti-fatigue and anti-stress effects range from 370 mg to 555 mg per day.
The researchers came to this conclusion by conducting a clinical trial1 with 161 young Russian cadets, aged 19 to 21. Cadets’ physical training ensures that they experience stress and fatigue on a daily basis.
Participants’ concentration and memorization abilities were measured through to-do tasks as prescribed by an anti-fatigue index. Participants who took rhodiola extract performed better than those who received only placebo or no treatment. Rhodiola allowed participants to improve their performance qualitatively rather than quantitatively.
One group of participants took three rhodiola capsules and another took only two. Each capsule contained 185 g of standardized extract (3%) of rhodiola root. The study authors did not observe any significant difference between the two doses (370 mg and 555 mg) in terms of the beneficial effects obtained.
Review HerbalGram, who criticized this clinical trial, has some reservations as to the reliability of the results. It evokes some problems of methodology. Indeed, the group receiving no treatment was not randomized, and the group taking three capsules was aware that the other group received only two, which may have influenced participants’ perceptions in the evaluation of the effects.
Rhodiola root extract has been part of traditional Russian medicine for a long time. In Denmark, the extract has been approved for commercial use as an adaptogenic herbal medicine that can be used to combat fatigue. An adaptogenic substance generally increases the body’s resistance to various stresses while causing minimal physiological effects. It is with this category of substances that rhodiola is associated.
Marie france Coutu – PasseportSanté.net
According to HerbalGram, issue 63, 2004.
1. Shevtsov VA, Zholus BI, Shervarly VI, et al. A randomized trial of two different doses of a SHR-5 Rhodiola rosea extract versus placebo and control of capacity for mental work.Phytomedicine. 2003 Mar; 10 (2-3): 95-105.
