Published in Phytotherapy Research, the report concluded that long-term supplementation with KSM-66 (Ixoreal Biomed Inc) and other ashwagandha root extracts led to only mild adverse events in just 9.4% of the 191 participants (men and women between the ags of 18 and 65).
“This study marks a pivotal milestone for the ashwagandha industry,” Kartikeya Baldwa, CEO of Ixoreal Biomed Inc., told NutraIngredients. “For the first time, we have a comprehensive long-term safety evaluation conducted on ashwagandha root, addressing a significant gap in the scientific literature that has persisted despite the ingredient’s growing popularity.”
“What makes this research particularly valuable is its scope,” he added. “The study evaluated KSM-66 ashwagandha alongside other ashwagandha root extracts that aren’t highly concentrated in withanolides, allowing for broader applicability of findings across the category.”
Safety was assessed across critical physiological markers, hepatic function, renal health, thyroid activity and hormonal balance, with no serious adverse events reported throughout the study period.
Baldwa added: “This kind of rigorous, peer-reviewed evidence provides the scientific credibility that consumers, healthcare practitioners and regulators have been seeking.”
Safety in question
The study, conducted by researchers in India, Italy and the United, was published amid a flurry of new research into the safety of the Ayurverdic herb in response to safety concerns raised by some European regulators.
Several experts have argued that questions over safety stem from adulteration and poor quality supplements.
Dr. Deepak Langade, lead author on the current study and head of the pharmacology department at D. Y. Patil University School of Medicine, India, told NI that safety concerns have largely stemmed from a handful of case reports not derived from controlled clinical studies.
“Importantly, the products consumed by the patients in these reports contained ashwagandha alongside other, unspecified ingredients,” he said. “We believe the adverse events may have been attributable to factors other than ashwagandha itself. In our view, the current level of concern in Europe is disproportionate and not supported by robust scientific evidence.”
Historically, traditional Ayurvedic practice utilized the root exclusively, as opposed to leaves or aerial portions.
“This selectivity wasn’t incident—ancient practitioners, through centuries of empirical observation, identified that different plant parts possessed different properties and risk profiles,” Baldwa said, adding that this study “fundamentally changes the conversation” around the safety of ashwagandha root extracts.
“Until now, the ashwagandha market has operated largely on traditional use claims and shorter-term efficacy data,” Baldwa noted. “Retailers and manufacturers had limited resources to point to when addressing consumer safety questions or navigating regulatory inquiries.”
He presents this study as an objective, independently verifiable reference point for retailers, manufacturers and consumers.
“Transparency isn’t just about publishing data, it’s about enabling informed decisions across the entire value chain,” he said. “That’s precisely what this research accomplishes.”
Study details
The prospective, multicenter, observational clinical study evaluated 12-month use of the KSM-66, a standardized aqueous ashwagandha root extract containing > 5% Withanolides (precisely estimated by the High-Performance Liquid Chromatography, HPLC) and negligible levels of withaferin A and withanone.
Participants received a capsule containing 300 mg capsules orally twice daily after meals with water and were asked to continue their routine diet and physical activities during the study period.
General examination and systemic examination (cardiovascular, respiratory, abdominal, nervous and musculoskeletal systems) was performed at baseline. Any history of significant medical disorders was recorded. Physical examination and vital parameters (pulse, sitting blood pressure, temperature and respiratory rate) were assessed at baseline and monthly up to 12 months.
In addition to the primary adverse events outcomes, the study also investigated for mean change in laboratory values for hepatic parameters, renal parameters, creatinine phosphokinase (indicator of effects on skeletal muscle), thyroid parameters, serum cortisol and serum testosterone (free and total testosterone) from baseline to six and 12 months. Quality of life (QoL) was assessed using the short form (SF-12) QoL questionnaire at baseline, six months and 12 months.
The data suggested that supplementation led to some reduction in serum cortisol and an increase in serum testosterone in both men and women, with no observed effects on lipid profile.
The researchers noted several limitations, including a relatively small sample size (n = 191), which limited the ability to detectrare or oridiosyncratic adverse effects that typically require larger populations to identify. In addition, the observational study design limited causal inference, and the absence of a placebo control limited comparative analysis.
Source: Phytotherapy Research, https://doi.org/10.1002/ptr.70096. “Safety of 12-Months Administration of Ashwagandha (Withania somnifera) Standardized Root Extract in Healthy Adults: A Prospective, Observational Study”. Authors: Langade, D. et al
