KSM-66 vs Sensoril vs Shoden: Ashwagandha Extracts Compared

Quick answer: KSM-66, Sensoril, and Shoden are the three branded ashwagandha extracts on the market. They differ in which parts of the plant they use, how they are extracted, and how concentrated they are in withanolides (the active compounds). KSM-66 has the deepest clinical research base, with ongoing trials continuing through 2026, and is the most widely studied for stress and testosterone support. Sensoril is most evidenced for sleep quality. Shoden has the highest withanolide concentration and is typically used at lower doses. The right choice depends on what you are trying to achieve and which compound your body tolerates best.

What is ashwagandha?

Ashwagandha, known scientifically as Withania somnifera, is a herb used in traditional Indian medicine for thousands of years. It is also called Indian ginseng or winter cherry, and grows across Africa, southern Asia, and central Asia.

Clinical research supports ashwagandha for:

Reducing cortisol and stress response in chronically stressed adults
Improving sleep quality, particularly onset latency
Modest testosterone support in men using it consistently
Improvements in strength, cardiorespiratory endurance, and recovery in training populations
Anxiolytic (anti-anxiety) effects

Most of this research has been conducted on branded, standardised extracts rather than generic ashwagandha powder, which is why the brand you choose matters.

How ashwagandha works: the role of withanolides

The active compounds in ashwagandha are a family of steroidal lactones called withanolides. Over 35 different withanolides have been identified in the plant, but only a handful are bioavailable enough to produce measurable effects in humans.

The main bioactive withanolides are:

Withanolide A: supports neurite outgrowth and nerve repair, with evidence for cognitive and anti-stress effects
Withanolide V (Withanoside V): neuro-regenerative, supports nerve growth
Withaferin A: antioxidant, anti-inflammatory, and anti-apoptotic activity
Withanolide B: anti-stress and immune-supportive

A standardised extract will list a total withanolide percentage on the label. This number is the single most useful spec when comparing products, because dose-for-dose potency scales with it.

The three extracts side-by-side

	KSM-66®	Sensoril®	Shoden®
Plant parts used	Root only	Root + leaf	Root + leaf
Withanolide concentration	5%	10%	35%
Extraction method	Milk-based, solvent-free	Water extraction	Ethanol + water dual extraction
Typical starting dose	500 mg	250 mg	70 mg
Typical upper dose	1000 mg	500 mg	200 mg
Published human trials	20+ (as of 2026)	12+ (as of 2026)	3+ (as of 2026)
Certifications	Organic, Non-GMO, Kosher, GRAS, Halal	Organic, Non-GMO, Kosher, GRAS, Halal	Non-GMO, Kosher, Halal, Vegan, Gluten-Free
On the market since	2012	2004	2017

KSM-66®

KSM-66 is the most studied branded ashwagandha extract. It uses only the root (not the leaf), extracted through a proprietary milk-based process that avoids alcohol and chemical solvents. It is standardised to a minimum 5% withanolide content.

Best evidence for: stress reduction, cortisol lowering, testosterone and male reproductive markers, strength and recovery in training populations.

Because it is root-only and uses a solvent-free extraction, KSM-66 has the longest real-world safety record of the three. It is also the most commonly found in supplement formulations globally.

Sensoril®

Sensoril is a root-and-leaf extract standardised to 10% withanolides using a water-based extraction. It has a larger clinical dataset on sleep-related outcomes than the other two.

Best evidence for: sleep quality, sleep latency, perceived anxiety reduction, general wellbeing in middle-aged and older adults.

The inclusion of leaf material raises withaferin A content, which some research suggests may contribute to its sleep and mood effects.

Shoden®

Shoden is the newest entrant. It is a root-and-leaf extract standardised to 35% withanolide glycosides, measured by HPLC. This makes it the most potent branded ashwagandha extract per milligram.

Best evidence for: cognitive function and brain health markers. Its clinical base is smallest, but the per-dose activity is high, allowing useful effects at 70 to 200 mg.

Because of its potency, Shoden is the extract you will see in capsules where space is tight (stacks, sleep blends, nootropic formulas) and where minimal bulk matters.

Which extract should you choose?

The honest answer is that there is overlap. All three extracts contain the same active compound family and produce similar physiological effects. The differences lie in which effects are best evidenced, not which effects occur at all.

Choose KSM-66 if:

Stress reduction is your primary goal
You are male and interested in testosterone or reproductive health support
You want the most clinical research behind your purchase
You prefer root-only, solvent-free extraction

Choose Sensoril if:

Sleep quality or sleep onset is your primary goal
You respond well to withaferin A-rich extracts
You want a middle ground between KSM-66's bulk and Shoden's concentration

Choose Shoden if:

Cognitive and brain health is your primary goal
You want the smallest possible capsule size (useful in stacks)
You tolerate higher-potency extracts well

An important caveat: the evidence differences partly reflect where each brand has chosen to fund research. Absence of evidence for a specific use is not evidence of absence. KSM-66 has simply been tested in more applications than the other two.

Recent research (2022 to 2026)

Ashwagandha has continued to accumulate clinical evidence since this article was first published. Several 2022 to 2026 trials are particularly relevant for training populations and those using ashwagandha for stress:

Training populations and athletes

A 2026 randomised controlled trial in 56 team-sport athletes (rugby, water polo, football) showed that 600 mg/day of ashwagandha root extract for 42 days stabilised cortisol response and improved perception of recovery during pre-season training, a period characterised by elevated training stress. Notably, the trial included equal numbers of male and female athletes.

A separate 2025 trial in professional female footballers found that 600 mg/day ashwagandha root extract improved perceived recovery and muscle strength. This fills a historic gap: most earlier ashwagandha research was conducted in men.

Stress and cortisol

A 2026 three-arm trial compared a proprietary ashwagandha root extract at 300 mg twice daily against generic ashwagandha root extract and placebo over 8 weeks in 141 adults with moderate stress and anxiety. The proprietary extract outperformed generic extract on stress and anxiety measures, reinforcing that the specific extract matters as much as the total withanolide dose.

A 2026 trial of a sustained-release ashwagandha formulation found that even a lower 150 mg daily dose produced meaningful stress reduction when delivered in a sustained-release matrix, suggesting that delivery method matters alongside dose.

Sleep and sex hormones

A 2023 trial of Witholytin (200 mg twice daily for 12 weeks) in overweight adults aged 40 to 75 reported improvements in stress, fatigue, and sex hormone markers, extending the testosterone evidence base to older adults and to a mixed-sex population.

A 2022 trial in 60 college students using 700 mg/day full-spectrum ashwagandha root extract for just 30 days showed measurable improvements in perceived stress, sleep quality, and food cravings, supporting shorter-duration effects than the 8-week standard.

Emerging branded extracts

Beyond the three established brands (KSM-66, Sensoril, Shoden), newer proprietary extracts have been published in 2023 to 2026, including Witholytin, Zenroot, AshwaSR, and APB. Each has published human trials. If you see these on a label, they are not unbranded ashwagandha, but the clinical dataset behind them is smaller than for the three extracts covered above. For buyers, the three main extracts still represent the best-researched choices as of 2026.

If sleep is your primary goal, consider apigenin

Ashwagandha can support sleep, particularly Sensoril, but in practice many of our customers find apigenin more effective for sleep specifically.

Apigenin is a flavonoid found concentrated in chamomile and parsley. It binds to the same GABA-A receptor sites as benzodiazepines and related sleep drugs, but without the dependency or next-day sedation. The result is faster sleep onset and deeper early-night sleep, with effects noticeable from the first dose rather than the 4 to 8 week build-up ashwagandha requires.

The two compounds work on different parts of the sleep problem, which is why running both is common:

Ashwagandha addresses the upstream cause of poor sleep: elevated cortisol, chronic stress, and sympathetic nervous system overdrive. Daily use, effects build over weeks.
Apigenin addresses the downstream mechanism: GABA-mediated sleep onset and maintenance. Taken as needed, effects appear on the same night.

If sleep is the outcome you care about most and you want something that works quickly, apigenin is usually the better starting point. If stress and cortisol are the root cause of your sleep problems, ashwagandha is the more durable solution. Many customers use both together.

Product: Nice Supplement Co Apigenin 98. 98% pure apigenin extract dosed at the clinically-studied 300 mg per capsule.

Full dosing and mechanism: Apigenin Dosage for Sleep: Why 300 mg is the Sweet Spot.

Dosing guide

Starting doses for new users:

KSM-66: 500 mg once daily
Sensoril: 250 mg once daily
Shoden: 70 mg once daily

Typical effective ranges for experienced users:

KSM-66: 500 to 1000 mg daily
Sensoril: 250 to 500 mg daily
Shoden: 70 to 200 mg daily

Ashwagandha works best taken consistently over 4 to 8 weeks. Acute single doses produce minimal effect. If you are not seeing benefit at the upper end of the range after 8 weeks, doubling the dose further is rarely productive. Consider switching extract type, looking at lifestyle factors, or trialling a different adaptogen entirely.

Timing: most research uses split doses (morning and evening) or a single evening dose when sleep is the primary target. For stress or cortisol management, morning dosing with food is a reasonable starting point.

Stacking: ashwagandha pairs well with apigenin for sleep support, with magnesium for stress and muscle recovery, and with adaptogens like rhodiola for daytime energy and resilience.

Ashwagandha supplements available at Strom Sports NZ

The ashwagandha-based products in our range use different extracts matched to different goals. Click through for dosing, ingredient lists, and clinical references for each.

Standalone

Strom Sports KSM-66 Ashwagandha
120 capsules at 500 mg KSM-66 per capsule. The direct, no-frills option if you want a clinical-dose ashwagandha without added ingredients. Ideal if you already take a multi or sleep formula and just want to add ashwagandha in isolation.

For stress and cortisol management

Leviathan Nutrition Vizure
A dedicated stress-support formula built around Shoden® ashwagandha alongside Rhodiola, Maca, Reishi, Cordyceps, Eleuthero, and Bacopa. Use this when chronic stress, elevated cortisol, or an overactive nervous system is the problem you are trying to solve, and you want Shoden's high-potency extract delivered in a complete adaptogen stack.

For daytime focus, cognition, and training performance

Strom SupportMAX Neuro
A nootropic formula combining 600 mg KSM-66 ashwagandha with 1000 mg choline, phosphatidylserine, Lion's Mane, and BioPerine. Designed for daytime cognitive load: work, training, study, competition prep.

Leviathan Nutrition Zenith Nootropic
A stimulant-free nootropic built around 600 mg KSM-66 ashwagandha, stacked with rhodiola, uridine monophosphate, ALCAR, Lion's Mane, and theanine. 20 servings. Use when you want daytime cognitive and stress support with a different ingredient profile to SupportMAX Neuro.

For sleep and evening recovery

Strom SupportMAX Neuro-PM
The evening counterpart to SupportMAX Neuro. Combines KSM-66 ashwagandha with sleep and recovery ingredients for wind-down, sleep onset, and overnight cognitive restoration. Use if you want ashwagandha paired with a full sleep-support stack rather than as a standalone.

Big Z Sleep Recovery Aid
A sleep-specific blend for recovery and deep sleep. Strongest choice when sleep is the single outcome you care about and ashwagandha is one component of a complete formula built specifically for that purpose.

If sleep is your primary goal, re-read the apigenin section above. Many customers find Nice Supplement Co Apigenin 98 more effective as a direct sleep aid, and use ashwagandha only to address the stress causing the sleep problem in the first place.

Frequently asked questions

Which ashwagandha is best for sleep?
Sensoril has the strongest published evidence specifically for sleep onset and sleep quality improvement, particularly in older adults. KSM-66 also has sleep studies but its strongest results are in stress and cortisol. For a sleep-first goal, Sensoril or a product built around Sensoril is the typical first choice. For many users, apigenin is a more effective sleep-specific option than any ashwagandha extract.

Is apigenin better than ashwagandha for sleep?
They work through different mechanisms. Apigenin works on the same GABA-A receptor site as benzodiazepines and produces faster sleep onset, usually noticeable from the first dose. Ashwagandha reduces cortisol and stress response over weeks of consistent use. For sleep specifically, many users find apigenin more effective. For stress driving poor sleep, ashwagandha is more durable. The two can be combined.

Is KSM-66 better than Sensoril?
KSM-66 has more published clinical trials (20+ vs 12+) and a longer real-world track record since 2012. "Better" depends on your goal. KSM-66 leads for stress and testosterone. Sensoril leads for sleep. They are closer than marketing materials suggest.

What is the difference between Shoden and KSM-66?
Shoden is standardised to 35% withanolides; KSM-66 is standardised to 5%. Shoden includes the leaf as well as the root; KSM-66 is root-only. Shoden is taken at 70 to 200 mg; KSM-66 at 500 to 1000 mg. KSM-66 has a much larger clinical research base. Shoden is newer and more potent per milligram.

Is 500 mg of ashwagandha enough?
For KSM-66, 500 mg is the standard evidence-based dose and what most clinical trials use. For Sensoril, 500 mg is toward the upper end of typical dosing. For Shoden, 500 mg is well above the effective range and not recommended.

How long does it take for ashwagandha to work?
Published trials show measurable effects on cortisol and stress markers at 4 to 8 weeks of consistent daily use. Shorter-duration 2022 research in college students found measurable effects at 30 days with 700 mg/day full-spectrum extract, so some users may notice earlier changes. Single doses produce minimal effect. If nothing is noticeable after 8 weeks at a clinical dose, further increases are rarely helpful.

Does ashwagandha work for women as well as men?
Most earlier ashwagandha research was conducted in men. Since 2022, trials in female athletes and mixed-sex populations have confirmed the stress, cortisol, and recovery benefits translate to women. Testosterone effects are male-specific but the broader stress, sleep, and training-recovery benefits apply to both sexes.

Can I take ashwagandha every day?
Yes. The branded extracts have been studied in daily-dose trials up to 12 weeks with good safety profiles. Longer-term daily use is common practice though less directly studied. If you want to cycle, 8 weeks on and 2 weeks off is a reasonable pattern, though not strictly required.

Which ashwagandha has the highest withanolide content?
Shoden, at 35% standardised withanolide glycosides, is the highest-concentration branded extract on the market.

References

Evaluation of the bioavailability of major withanolides of Withania somnifera using an in vitro absorption model system. Journal of Advanced Pharmaceutical Technology and Research, October 2015.
An investigation into the stress-relieving and pharmacological actions of an ashwagandha extract. Medicine (Baltimore), September 2019.
Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study. Cureus, December 2019.
Efficacy and Tolerability of Ashwagandha Root Extract in the Elderly for Improvement of General Well-being and Sleep: A Prospective, Randomized, Double-blind, Placebo-controlled Study. Cureus, February 2020.
Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial. Journal of the International Society of Sports Nutrition, November 2015.
Efficacy of Ashwagandha in improving cardiorespiratory endurance in healthy athletic adults. Ayu, January 2015.
The Impact of Ashwagandha on Stress, Sleep Quality, and Food Cravings in College Students: A Double-Blind Randomized Control Trial. Journal of Medicinal Food, August 2022. DOI: 10.1089/jmf.2022.0040
Exploring the efficacy and safety of a novel standardized ashwagandha root extract (Witholytin) in adults experiencing high stress and fatigue. Journal of Psychopharmacology, September 2023. DOI: 10.1177/02698811231200023
A standardized Ashwagandha root extract alleviates stress, anxiety, and improves quality of life in healthy adults by modulating stress hormones. Medicine (Baltimore), October 2023. DOI: 10.1097/MD.0000000000035521
Effects of root extract of Ashwagandha on perception of recovery and muscle strength in female athletes. European Journal of Sport Science, March 2025. DOI: 10.1002/ejsc.12265
Ashwagandha Root Extract Stabilises Physiological Stress Responses in Male and Female Team Sports Athletes During Pre-Season Training. Nutrients, January 2026. DOI: 10.3390/nu18020230
Efficacy and safety of Ashwagandha root extract sustained-release (AshwaSR) capsules in healthy stressed adults. Medicine (Baltimore), March 2026. DOI: 10.1097/MD.0000000000047990

Research sourced via PubMed, National Library of Medicine.