KSM-66 vs Shoden — which ashwagandha extract is better?

Both are legitimate, well-studied root extracts; they just concentrate differently. KSM-66 is root-only, standardized to about 5% withanolides, and is the most researched extract (used in most stress trials) at 300-600mg/day. Shoden is a higher-potency extract standardized to roughly 35% withanolides, so it is dosed at much smaller doses (around 120-240mg) and features in several sleep studies. Neither is clearly superior — choose by extract type and follow the label dose.

How much ashwagandha should I take per day?

Trials most often used 300-600mg per day of a standardized root extract (like KSM-66), typically split into two doses or taken once daily, for at least 8 weeks. Higher-potency extracts like Shoden are dosed lower (about 120-240mg) because they contain more withanolides per milligram. More is not better — stay within the studied range.

Is ashwagandha safe? Are there risks?

Ashwagandha has mostly been studied for 8 to 12 weeks, and there are real cautions. Rare cases of liver injury have been reported, so stop and see a doctor if you notice yellowing skin, dark urine, or unusual fatigue. Do not take ashwagandha if you are pregnant (it may cause miscarriage). Use caution if you have a thyroid condition (it can raise thyroid hormone levels), an autoimmune disease, or take sedatives or immunosuppressants. Long-term safety beyond a few months is not well established.

Best Ashwagandha (2026): KSM-66 vs Shoden, Ranked by Dose & Cost

Q: What is the best ashwagandha supplement?

For most people the best ashwagandha is a KSM-66 root extract at 300-600mg per day — it is the most clinically studied extract, standardized to root only with at least 5% withanolides. Best value on cost per day is Nootropics Depot KSM-66 (~$0.25/day at 300mg). For a higher-potency option, Thorne Ashwagandha uses Shoden extract; the listing says NSF Certified for Sport, but we could not confirm that SKU in the public registry. Match the dose to the studies: 300-600mg/day of a standardized extract.

By Erin Rose · Updated May 30, 2026 · Methodology · About Us

Buy a standardized root extract at the studied dose. The two that matter are KSM-66 (root-only, ~5% withanolides, the most-researched, dosed 300-600mg/day) and Shoden (higher-potency ~35%, dosed lower). Skip cheap "generic root" with no standardization.

Best value: Nootropics Depot KSM-66 — 300mg, ~$0.25/day. Budget KSM-66: Jarrow KSM-66. Higher-potency Shoden: Thorne (Shoden).

What has been studied: stress and perceived anxiety (most research), sleep, and muscle strength in men. For stress · for sleep.

Best ashwagandha, ranked

Ashwagandha supplements ranked by cost per day
Product	Extract	Dose	Servings	Price	Cost/Day	Certification (as listed; not confirmed in a public registry)	Buy
NOW Foods Ashwagandha Extract (450mg, 90ct)	Generic root (~2.5%)	450mg	90	$9.85	$0.11	None	Buy
Jarrow Formulas Ashwagandha KSM-66 (300mg, 120ct) Budget Pick	KSM-66 (5% withanolides)	300mg	120	$22.93	$0.19	None	Buy
Nootropics Depot KSM-66 Ashwagandha (300mg, 90ct) Best Value	KSM-66 (5% withanolides)	300mg	90	$22.99	$0.25	Third-Party Tested	Buy
Thorne Ashwagandha (Shoden, 120mg, 30ct) Quality Pick	Shoden (~35% withanolides)	120mg	30	$22.00	$0.73	NSF Certified for Sport (brand-stated; not confirmed in the public registry)	Buy

Which to pick

Best value: Nootropics Depot KSM-66

Nootropics Depot KSM-66 gives you the most-researched extract at a studied 300mg dose, for about $0.25/day. It is our best-value pick on cost per day.

Higher-potency pick: Thorne (Shoden)

Thorne Ashwagandha uses high-potency Shoden. Its listing mentions NSF Certified for Sport, but we could not find this SKU in the public NSF registry, so we do not count it as confirmed. It costs more per day, and Shoden has more of the sleep research.

Budget KSM-66: Jarrow

Jarrow KSM-66 is also a KSM-66 extract. Compare its price per day in the table above.

The only thing that matters: extract and dose

Ashwagandha has been studied in clinical trials, but only at the doses and extracts that were actually studied. The single biggest mistake is buying "ashwagandha root powder, 1000mg" with no standardization and assuming it matches the research. It doesn't. What was tested were standardized extracts, and two dominate the literature.

The two extracts worth buying
	KSM-66	Shoden
Source	Root only	Root + leaf, high-concentration
Standardization	~5% withanolides	~35% withanolides
Studied dose	300-600mg/day	~120-240mg/day
Most research	Stress, cortisol	Sleep
Research volume	Most-studied extract	Newer, growing

Withanolides are the active compounds, which is why a 120mg Shoden capsule can match a 600mg KSM-66 dose — it's more concentrated. Don't compare ashwagandha products by milligrams alone; compare by extract type and the dose on the label.

What has been studied

Stress and anxiety scores: A randomized, placebo-controlled trial of a Shoden extract measured perceived stress and morning cortisol (Lopresti 2019, PMID: 31517876), and a 2022 meta-analysis of RCTs looked at anxiety and stress scores (Akhgarjand 2022, PMID: 36017529). Trials were small and results varied.
Sleep scores: A systematic review and meta-analysis looked at sleep outcomes across doses and durations (Cheah 2021, PMID: 34559859). Trials were small and results were mixed.
Muscle strength in men: One RCT studied ashwagandha together with resistance training (Wankhede 2015, PMID: 26609282). It was a single small trial.

Safety: the part most "best ashwagandha" lists leave out

Ashwagandha has mostly been studied over short periods, and it is not risk-free:

Liver injury (rare but real): Documented cases of ashwagandha-associated liver injury exist. Stop and see a doctor if you develop yellowing of the skin/eyes, dark urine, nausea, or unusual fatigue. Full picture, including how that compares to FDA adverse-event data: ashwagandha liver safety.
Pregnancy: Do not use — it may cause miscarriage.
Thyroid: It can raise thyroid hormone levels. If you have a thyroid condition or take thyroid medication, talk to your doctor.
Autoimmune disease: It may stimulate immune activity; caution with autoimmune conditions and immunosuppressant drugs.
Sedatives: Effects can be additive with sedatives and alcohol.
Duration: Most studies ran 8-12 weeks. Long-term safety beyond a few months isn't well established, and no trial tested taking breaks.

Safety summary drawn from the NIH Office of Dietary Supplements fact sheet.

Price check · Ashwagandha

What Ashwagandha actually costs across the brands we track

6.6×the gap in cost per day between the cheapest and the priciest Ashwagandha product we track: $0.11 against $0.73, from 4 brands

What you pay. The 4 Ashwagandha products here run $0.11 to $0.73 a day across 4 brands, a 6.6× gap. Some of these state a certification on the listing itself. That is a weaker claim than a certifier confirming it: a listing repeats what the brand says, and a registry entry shows what a certifier has checked.

Method: the 4 Ashwagandha products in our catalogue, each priced at its own labelled serving rather than by pack size, across 4 brands. How we price.

The shelf · Ashwagandha

The Ashwagandha shelf is unusually consistent

6.6×the gap in cost per day between the cheapest and the priciest product here

Across 4 products from 4 brands, the cheapest day is NOW Foods Ashwagandha Extract (450mg, 90ct) at $0.11 and the priciest is Thorne Ashwagandha (Shoden, 120mg, 30ct) at $0.73, a gap of 6.6×. With prices this close, which of these Ashwagandha products has been independently checked matters more than the price.

Method: the 4 Ashwagandha products above, compared on label facts, serving size, servings per container, form, price. Not a dosing recommendation.

Frequently asked questions

What is the best ashwagandha supplement?

A KSM-66 root extract at 300-600mg/day for most people — most studied, standardized. Best value on cost per day: Nootropics Depot KSM-66 (~$0.25/day at 300mg). For a higher-potency option: Thorne (Shoden).

KSM-66 vs Shoden — which is better?

Both are legitimate. KSM-66 is root-only (~5% withanolides, 300-600mg, most-researched, most stress data). Shoden is higher-potency (~35%, ~120-240mg, more sleep data). Pick by extract type and follow the label dose.

How much should I take?

300-600mg/day of a standardized extract like KSM-66 for at least 8 weeks. Higher-potency Shoden is dosed lower (~120-240mg). More isn't better.

Is it safe?

Rare liver-injury cases exist; avoid in pregnancy; use caution with thyroid conditions, autoimmune disease, sedatives, and immunosuppressants. Long-term safety isn't well established.

Related guides

Ashwagandha: stress research and picks
Ashwagandha and sleep research
KSM-66 vs Sensoril
Ashwagandha Liver Safety — case reports vs. FDA adverse-event data, in full
All Ashwagandha Products

Sources

Lopresti AL, et al. "An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract." Medicine (Baltimore). 2019;98(37):e17186. PMID: 31517876
Akhgarjand C, et al. "Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of RCTs." Phytother Res. 2022;36(11):4115-4124. PMID: 36017529
Cheah KL, et al. "Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis." PLoS One. 2021;16(9):e0257843. PMID: 34559859
Wankhede S, et al. "Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial." J Int Soc Sports Nutr. 2015;12:43. PMID: 26609282
NIH Office of Dietary Supplements. "Ashwagandha: Is it helpful for stress, anxiety, or sleep?" ods.od.nih.gov