A plant we've trusted for 3,000 years.
Now measured by modern science.
Ashwagandha isn't a wellness trend. It's one of the most-studied botanicals in human history — and the main active in Carmelwell Steady. Here's the actual research, with every study linked so you can read it yourself.
One of the longest-used medicinal plants on earth
Ashwagandha (Withania somnifera) has been central to Ayurvedic medicine for around three thousand years, with the earliest surviving written descriptions appearing in the classical Ayurvedic texts.
In the Ayurvedic system it's classified as a Rasayana — a category of rejuvenating tonics intended for daily use across a lifetime to support vitality, resilience, and healthy aging. The Charaka Samhita, one of the foundational texts of Ayurvedic medicine, describes it for physical strength, cognitive support, and recovery from stress and depletion.
The name itself is telling. "Ashwagandha" roughly translates from Sanskrit as "the smell of a horse" — a nod both to the root's scent and to the strength and stamina it was traditionally believed to confer. Its species name, somnifera, is Latin for "sleep-bringing."
What generations of practitioners observed through centuries of use, modern researchers have spent the last two decades measuring under controlled conditions. Encouragingly often, the lab has agreed with the tradition.
Not all ashwagandha is the same
Most inexpensive ashwagandha supplements use generic powder — often a blend of root and leaf, with no standardization of how much active compound is actually inside. Two products can both say "ashwagandha" on the label and deliver very different things.
Steady uses KSM-66®
KSM-66® is a root-only extract standardized to 5% withanolides (the plant's key active compounds), produced by Ixoreal Biomed. It is one of the most extensively researched forms of ashwagandha in the world — the subject of over 20 human clinical trials, all using randomized, double-blind, placebo-controlled designs.8
When you see a headline about ashwagandha lowering cortisol or improving sleep, the study behind it was very often conducted on KSM-66® or an equivalent root-standardized extract. Steady uses it at 600mg — the daily amount used in the clinical trials, not a token dusting for the label.
The evidence, study by study
Below are the strongest human trials, grouped by what they measured. We've noted the design and dose for each, and linked the source. Where the evidence is strong, we say so plainly — and where it's still emerging, we say that too.
Stress & anxiety — the strongest evidence
Pooled across a dozen trials: significant stress & anxiety reduction
The highest tier of evidence isn't a single study — it's what happens when you pool many. A 2022 systematic review and meta-analysis combined 12 randomized controlled trials with 1,002 participants (age range 25–48 — almost exactly the years this matters most). It found ashwagandha supplementation significantly reduced both anxiety and stress versus placebo, with the strongest effects clustering around 300–600mg a day. The authors rated the overall certainty of the evidence as low, which is common in botanical research and worth knowing.1
Cortisol fell 27.9% over 60 days
In a 60-day trial of 64 chronically stressed adults, participants taking 300mg of KSM-66® twice daily (600mg total) saw serum cortisol — the body's primary stress hormone — drop by 27.9%, versus 7.9% in the placebo group. Stress-scale scores fell sharply across all three measures used (Perceived Stress Scale, GHQ-28, and DASS), with strong statistical significance.2
Replicated with KSM-66® at 600mg/day
A separate KSM-66® trial in healthy, stressed adults confirmed the pattern: 600mg/day significantly reduced stress and anxiety scores and lowered serum cortisol compared to placebo, and was well-tolerated with only mild effects comparable to the placebo group.3
Lower morning cortisol and anxiety
In a 60-day study of stressed adults, a standardized ashwagandha extract produced a significant reduction on the Hamilton Anxiety scale and greater reductions in morning cortisol versus placebo — further evidence that the effect on the body's stress axis is real and repeatable.4
Sleep — meta-analysis-level evidence
Significant improvement in overall sleep
A 2021 systematic review and meta-analysis pooled five randomized controlled trials covering 400 participants. It found ashwagandha extract had a small but statistically significant effect on overall sleep — with the effects most prominent at doses of 600mg/day or higher, taken for eight weeks or longer. It also improved reported mental alertness on waking, with no serious side effects across the included trials.5
Fell asleep faster, slept more efficiently
A trial using KSM-66® specifically — the exact extract in Steady — found that participants fell asleep meaningfully faster (sleep onset latency dropped about 30%) and spent more of their time in bed actually asleep (sleep efficiency rose about 10%), with a statistically significant improvement in overall sleep quality versus placebo.6
Energy & endurance
Measurably better cardiovascular endurance
"Energy" is easy to claim and hard to measure — so this trial measured it directly. Over 12 weeks, healthy athletic adults taking KSM-66® (600mg/day) improved their VO₂ max — the gold-standard measure of cardiorespiratory endurance — by 13.6%, versus 4.4% in the placebo group. Quality-of-life scores improved across physical, psychological, and social measures too. Worth noting the population: these were trained adults, so the size of the effect won't necessarily transfer to someone starting from a sedentary baseline.7
For women specifically
Most ashwagandha research has been done in mixed adult populations. But a focused and growing body of work looks specifically at women — and on the questions that matter most in the 35–55 window (the hormonal transition, mood, sleep, day-to-day wellbeing), the results have been remarkably consistent across independent trials.
Perimenopause symptoms improved over 8 weeks
In an 8-week trial of 100 perimenopausal women, ashwagandha root extract (300mg twice daily) significantly reduced total Menopause Rating Scale scores versus placebo, with improvements across the psychological, somatic and urogenital domains — and significantly improved menopause-specific quality of life.9
Independently replicated — using the extract in Steady
A separate trial of 60 women aged 45–55 found the same pattern, which is exactly what you want to see before trusting a result. Over 8 weeks, Menopause Rating Scale scores fell significantly across all three domains, hot-flash events decreased, and perceived stress scores dropped significantly versus placebo. This trial used KSM-66® specifically — the same extract, at the same daily amount, that's in Steady.10
Ashwagandha and shatavari, studied together
Steady's hormonal half rests on two botanicals rather than one — so the most relevant trial is the one that tested them side by side. Over 24 weeks, 123 postmenopausal women aged 40–55 received ashwagandha alone, shatavari alone, the two combined, or placebo. Menopause-specific quality-of-life scores improved dose-dependently against placebo. It's the only controlled trial we're aware of that studies this particular pairing.11
Mental clarity & focus
Memory, focus, and information processing
An 8-week study found ashwagandha root extract improved measures of memory, executive function, attention, and information-processing speed compared to placebo — partly a direct effect, and partly through the downstream benefit of lower stress and better sleep clearing the fog that chronic stress creates.12
An adaptogen, not a sedative
Chronic stress keeps your HPA axis — the hypothalamic-pituitary-adrenal system that governs your stress response — stuck in an overactive state, flooding your body with cortisol. That's what disrupts sleep, drains energy, and keeps you feeling tired-but-wired.
Why this changes from your mid-30s
Estrogen helps regulate that same HPA axis. Think of the stress response as having an accelerator and a brake — estrogen helps work the brake. Researchers at USC tested this directly: postmenopausal women who had been on estradiol therapy for around five years showed a smaller cortisol rise after a physical stressor, and unlike the placebo group, no drop in working memory afterwards.13
So as estrogen begins to fluctuate and fall — which can start in the mid-30s — the brake weakens. The same amount of stress produces a bigger cortisol response, and it takes longer to clear.
There's a second half to it. Progesterone is produced only after ovulation, and it's the calming, sleep-supporting hormone. As ovulation becomes less regular through the transition, progesterone falls — so sleep gets lighter and more broken.14 Poor sleep raises stress load, which raises cortisol, which makes sleep worse again.
That's the loop. And it's why a product aimed only at cortisol is addressing half of it.
What ashwagandha does in that picture
Ashwagandha's withanolides act on the stress axis to help normalize an over-elevated cortisol response, rather than forcing a stimulant "up" or a sedative "down." That's the meaningful distinction: it's not knocking you out, and it's not a jolt of energy — it's helping your body's own regulation return toward baseline. This is exactly why it isn't instant.
Sleep is often the first thing people notice — falling asleep more easily, waking less.
A calmer daily baseline as the stress response begins to settle.
The cortisol and stress benefits measured in the trials become meaningful — matching the clinical timelines.
That gradual build isn't a limitation — it's how genuine, lasting adaptogenic support works. The trials that produced the numbers above ran for six to twelve weeks of consistent daily use, and were consistently well-tolerated with minimal side effects.
"I didn't build Carmelwell because ashwagandha was trending. I've taken it daily for years — long before I had any reason to sell it — and I know what it did for my own sleep and for my ability to get through a hard day without it costing me the evening."
"Steady is the version I wanted to exist. The clinically studied extract, at the dose the research actually used, combined with the botanicals that cover the other half of the problem. I've been on this exact formula for months now. I sleep better on it, and I handle stress better on it. That isn't a promise about what it'll do for you — everyone is different, and the 60-day guarantee exists for precisely that reason. But I'm not asking you to try something I don't take myself every day."
— Founder of the Carmelwell
Steady puts the research in a bottle
KSM-66® at the clinically studied 600mg, plus seven supporting botanicals and nutrients — built for stress, sleep, and steady energy.
Explore Steady →References
- Akhgarjand C, Asoudeh F, Bagheri A, et al. Does ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trials. Phytotherapy Research, 2022. pubmed.ncbi.nlm.nih.gov/36017529
- Chandrasekhar K, Kapoor J, Anishetty S. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian Journal of Psychological Medicine, 2012. pmc.ncbi.nlm.nih.gov/articles/PMC3573577
- Salve J, Pate S, Debnath K, Langade D. Adaptogenic and anxiolytic effects of ashwagandha root extract in healthy adults: a double-blind, randomized, placebo-controlled clinical study. Cureus, 2019. pmc.ncbi.nlm.nih.gov/articles/PMC6979308
- Lopresti AL, Smith SJ, Malvi H, Kodgule R. An investigation into the stress-relieving and pharmacological actions of an ashwagandha extract: a randomized, double-blind, placebo-controlled study. Medicine, 2019. pmc.ncbi.nlm.nih.gov/articles/PMC6750292
- Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R. Effect of ashwagandha (Withania somnifera) extract on sleep: a systematic review and meta-analysis. PLOS One, 2021. pubmed.ncbi.nlm.nih.gov/34559859
- Langade D, Kanchi S, Salve J, et al. Efficacy and safety of ashwagandha (Withania somnifera) root extract in insomnia and anxiety: a double-blind, randomized, placebo-controlled study. Cureus, 2019. pubmed.ncbi.nlm.nih.gov/31728244
- Choudhary B, Shetty A, Langade DG. Efficacy of ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults. AYU, 2015. pubmed.ncbi.nlm.nih.gov/26730141
- KSM-66 Ashwagandha clinical research overview. Ixoreal Biomed. ksm66ashwagandhaa.com/science.php
- Gopal S, Ajgaonkar A, Kanchi P, et al. Effect of an ashwagandha (Withania somnifera) root extract on climacteric symptoms in women during perimenopause: a randomized, double-blind, placebo-controlled study. Journal of Obstetrics and Gynaecology Research, 2021. pubmed.ncbi.nlm.nih.gov/34553463
- Vani I, Muralidhar G, Rao BS. A prospective, randomized, double-blind, placebo-controlled study on efficacy and safety of ashwagandha root extract for managing menopausal symptoms in women. Frontiers in Reproductive Health, 2026. frontiersin.org/journals/reproductive-health
- Pingali U, Nutalapati C, Wang Y. Ashwagandha and shatavari extracts dose-dependently reduce menopause symptoms, vascular dysfunction, and bone resorption in postmenopausal women: a randomized, double-blind, placebo-controlled study. Journal of Menopausal Medicine, 2025. pubmed.ncbi.nlm.nih.gov/40347163
- Choudhary D, Bhattacharyya S, Bose S. Efficacy and safety of ashwagandha (Withania somnifera) root extract in improving memory and cognitive functions. Journal of Dietary Supplements, 2017. pubmed.ncbi.nlm.nih.gov/28471731
- Ycaza Herrera A, Hodis HN, Mack WJ, Mather M. Estradiol therapy after menopause mitigates effects of stress on cortisol and working memory. The Journal of Clinical Endocrinology & Metabolism, 2017. academic.oup.com/jcem/article/102/12/4457
- Santoro N. Perimenopause: from research to practice. Journal of Women's Health, 2016. pmc.ncbi.nlm.nih.gov/articles/PMC4834516