GoKawiilMohammed Gulrez Zariwala (right) thinks that clearer communication from researchers working on supplements will benefit the public.Credit: Unity/University of Westminster
The roots of the shrub Withania somnifera have been used in the traditional Indian practice of Ayurvedic medicine for millennia. In ancient texts, dating from around the second century bc, the herbal extract — which is more commonly known as ashwagandha today — is described as a powerful tonic that can help the mind and body to build resilience.
In the past few years, ashwagandha supplements have exploded in popularity, with worldwide use estimated to have quadrupled since 2020. In keeping with its traditional use, the plant is best known for its ability to calm and soothe. However, social-media platforms are awash with posts saying that the root not only reduces stress and improves sleep, but also boosts energy and testosterone levels, supports cognitive health and lowers inflammation. Companies marketing the supplements often say that the products improve metrics such as emotional balance, energy or immunity.
Nature Spotlight: Nutrition
Although ashwagandha’s rise has been buoyed by numerous studies supporting its benefits, the evidence is not clear cut. A systematic review of 22 trials showed that the herb significantly improved stress, depression and anxiety (S. A. Alsanie et al. Complement. Ther. Med. 97, 103325; 2026). However, the authors also noted that the studies were generally low in quality and varied in what they measured, stating that “ashwagandha should not yet be regarded as a definitive treatment option but rather as a promising complementary strategy that warrants further investigation”.
Ashwagandha’s new-found fame has also drawn the attention of regulators. The French Agency for Food, Environmental and Occupational Health and Safety issued a warning advising against its use by pregnant people, children and individuals with various medical conditions. The UK Food Standards Agency is also reviewing its safety. Supplements containing the compound were banned in Denmark in 2023.
However, the Indian government’s Ministry of Ayush, which is responsible for traditional medicine, published a report in 2024 that reaffirmed ashwagandha’s safety and criticized the Danish regulator’s assessment, stating “like any other medicinal preparation, be it paracetamol or antibiotics, there could be adverse events with herbal products in some individual [sic]” (available at go.nature.com/4asa2yk).
Ashwagandha is not the only supplement to have surged in popularity in the past decade. Previously niche wellness products, such as collagen, lion’s mane mushroom and probiotics have become mainstream, and sales of long-standing supplements such as magnesium, omega-3 and vitamin D have also increased. By some estimates, at least 60% of all US and European adults take supplements regularly. In the first half of 2025, one-fifth of adults in the United Kingdom took a wellness supplement, including collagen, ashwagandha and a mushroom powder. The value of the global dietary-supplements market was estimated at nearly US$152 billion in 2021. According to one 2022 estimate, it is expected to be worth $300 billion by 2028 (O. Djaoudenne et al. Nutrients 15, 3320; 2023).
Much of this growth is driven by products that promise ‘science-backed’ benefits. But as supplements become more popular, issues of scientific ambiguity similar to those that surround ashwagandha are likely to grow. Mohammed Gulrez Zariwala, a translational physiologist at the University of Westminster, in London, says that regulators are already trying to catch up, tasked with ensuring that new products are safe and can achieve the bigger and better benefits that their makers promise. “It’s become a bit of a wild west,” he says. “Companies and marketeers go to extremes with their claims, and then the regulators rein them in.” At this murky confluence of industry, advertising and governance, can science help to bring some clarity?
Routes to remedies
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