Herbal adaptogens – specific botanicals historically used in traditional medicine – enhance the efficiency of the body’s adaptive response to physical, chemical or biological stressors.
Rhodiola rosea (Golden root) and Ashwagandha (Withania somnifera or Indian ginseng) are classical plant adaptogens that promote stress resilience while counteracting stress-associated alterations such as anxiety, nervousness, irritability, insomnia and depression.
Botanical ingredients supplier Nektium and the University of Las Palmas de Gran Canaria in Spain evaluated both ingredients in a scientific review study for the European Journal of Medicinal Plants.
Analysing existing in vitro, in vivo and clinical trials, they found that the overall evidence clearly indicates that both adaptogens have effective anti-stress activity.
Rhodiola rosea
Rhodiola rosea works by modulation of the central nervous system.
In 2011, the European Medicines Agency’s herbal monograph on Rhodiola rosea approved its traditional use as an adaptogen for the temporary relief of symptoms associated with stress, such as fatigue, exhaustion and a general sensation of weakness.
The new review study considered more than 70 human clinical trials on Rhodiola rosea, which were of varying quality in methodology, design and conditions.
Despite these limitations, there was a clear level of evidence to demonstrate that Rhodiola rosea can effectively combat physical stress-related fatigue, low mood, anxiety, depression and may improve physical-mental working capacity.
Ashwagandha
Ashwagandha, meanwhile, could work by a similar or additional neuromodulatory mechanism.
The clinical efficacy of its preparations and extracts has now been demonstrated across a large number of human trials.
They support Ashwagandha’s potential therapeutic role as an adaptogenic anti-stress agent and in counteracting stress-related conditions, especially anxiety, nervousness and insomnia.
Safety profile
The review also assessed the evidence on the safety of both adaptogens.
In April 2023, Denmark announced a ban on Ashwagandha after a risk assessment failed to establish a safe lower limit for intake.
This study presents a favourable picture of Ashwagandha’s overall safety; however, it showed there is growing data concerning interactions with specific medications and potential adverse effects in susceptible individuals or those with certain health conditions or subclinical disorders.
The review found that Rhodiola rosea can be considered safe and is generally well tolerated in individuals with a wide variety of health statuses, although caution is required when consuming Rhodiola rosea alongside psychotropic medication.
Rubén P. Machín, PhD, Project Manager – Research, Development & Innovation at Nektium, said: “Both adaptogens show effective anti-stress activity, but their specific mechanisms of action differ. Rhodiola rosea, with its impact on the central nervous system, demonstrates improvement in stress-induced fatigue, depression and enhanced mental and physical performance. Ashwagandha, on the other hand, exhibits serotonergic-dependent antidepressant effects and modulates GABAergic neurotransmission, potentially making it more effective against stress-associated anxiety, nervousness, and insomnia.”
