Ashwagandha and Insomnia — What Did the Clinical Trial Show About Sleep Quality?

In our knowledge-base entry on ashwagandha, we describe it as one of the best-studied adaptogens, whose most strongly documented effect concerns the hypothalamic-pituitary-adrenal axis and cortisol levels. In another of our articles, ashwagandha and cortisol, we show that a drop in blood cortisol doesn't always translate into felt stress relief — the two effects can drift apart. This article, however, tackles a different, narrower question: does ashwagandha help specifically with sleep, and not in the general population of stressed, poorly-sleeping adults, but in people with clinically diagnosed insomnia.

This distinction matters methodologically, not just semantically. Many studies on adaptogens and sleep recruit people "with elevated stress levels," in whom worse sleep is just one of many secondary outcomes measured. The study behind this article did something different — it recruited patients meeting the criteria for insomnia and anxiety as the primary focus, and measured sleep quality not just with a questionnaire, but with objective actigraphy: a wrist-worn device that records actual movement and sleep time, rather than relying only on a participant's subjective account the next morning.

The study was conducted at Prakruti Hospital in Kalwa, in the state of Maharashtra, India, as a randomized, double-blind, placebo-controlled trial. Participants were patients with diagnosed insomnia and accompanying anxiety — not a general population reporting "worse sleep," but people meeting the clinical criteria for these two related conditions.

The hypothetical mechanism through which ashwagandha could support sleep largely overlaps with the one described in our article on ashwagandha and cortisol — withanolides modulating the HPA axis and a potential effect on GABAergic receptors, also described in our knowledge-base entry on ashwagandha. Excessive activation of the stress axis is linked to elevated evening cortisol, which makes both falling asleep and maintaining deep sleep harder — so a reduction in this activation is the most commonly cited explanation for the observed improvement in sleep parameters.

The key difference from the cortisol article, however, lies in participant selection. The meta-analysis described there covered studies across various populations, not necessarily people with diagnosed insomnia — a drop in cortisol there didn't necessarily mean better sleep for people with a real problem falling asleep. The study by Langade and colleagues, described in this article, specifically recruited people with diagnosed insomnia and anxiety, making it a more direct test of this particular hypothesis — one that helps answer the question that actually matters to someone struggling to fall asleep, rather than just someone with generally elevated stress.

Many studies on supplements and sleep rely solely on sleep diaries or questionnaires filled out by participants the next morning — methods susceptible to memory bias and expectation effects (a participant who knows they're testing something meant to improve sleep may subjectively rate it more favorably regardless of any real physiological change). Actigraphy, which records movement via a wrist-worn device, provides a more objective approximation of actual sleep time and the number of awakenings, independent of how the participant remembered their night.

This doesn't mean actigraphy is a perfect method — the gold standard in sleep research remains laboratory polysomnography, which additionally records brain activity and allows distinguishing individual sleep stages, described in more detail in our entry on sleep. Actigraphy is nonetheless a clear step up from questionnaires alone, and one of the reasons this particular study deserves to be taken more seriously than many others that rely solely on participants' subjective assessments.

It's also worth remembering that the study didn't differentiate between causes of participants' insomnia. Insomnia is often secondary to a range of distinct problems — chronic pain, depression, sleep apnea, an irregular circadian rhythm, or excessive evening caffeine, as we discuss in our article on caffeine and sleep. Ashwagandha, likely acting mainly through the stress axis, has the best chance of helping where elevated stress and anxiety genuinely coexist with insomnia — not necessarily where the cause lies elsewhere entirely.

This study stands out among many other publications on ashwagandha and sleep by deliberately recruiting patients with diagnosed insomnia, rather than a general, stressed population, and by using objective actigraphic measurement instead of relying solely on subjective self-report. That's a genuine methodological advantage worth acknowledging.

At the same time, the sample size, single research center, and the numerical inconsistency in the abstract itself call for caution in drawing final conclusions. Ashwagandha looks like a promising, but not definitive, element of a sleep-support strategy for people whose insomnia coexists with elevated anxiety — not a standalone solution for every kind of sleep problem.