Rhodiola contains a number of potentially active compounds, including phenylpropanoids (rosavin, rosin, rosarin),; phenylethanol derivatives (salidroside [also known as rhodioloside], tyrosol); flavonoids (rodiolin, rodionin, rodiosin, acetylrodalgin, tricin); monoterpenes (rosiridol, rosaridin); triterpenes (daucosterol, beta-sitosterol); and phenolic acids (chlorogenic, hydroxycinnamic, and gallic acids). The presence of rosavin distinguishes the species R. rosea from other rhodiolas, and many products are standardized to rosavin content to ensure that they contain the proper species.
There are numerous animal and test tube studies showing that rhodiola has both a stimulating and a sedating effect on the central nervous system (depending on intake amount); enhances physical endurance; improves thyroid, thymus, and adrenal function; protects the nervous system, heart, and liver; and has antioxidant and anticancer properties.2