Double Wood KSM-66 Ashwagandha 600 mg Review
#2 of 7 · Best budget✓ Label verified · Supplement Facts read Aug 27, 2026Real retailer photo, cut out. Label unedited.
Buy it. The default first-time KSM-66 buyer pick — trial-dose-exact, KSM-66(R) licensed, and the cheapest of the three at that dose. KSM-66(R) + 600 mg per 2-capsule serving (300 mg per cap — exact Wankhede 2015 / Chandrasekhar 2012 dose) + about $9-10/month, undercutting the $14/month Nutricost quote at the same dose.
$22 / month (2 caps/day)~$22 / month at the 600 mg trial dose (2-cap serving)
Why It Scores 8.8 — And The Label Line Behind Each Number
Standardisation
30% of scoreKSM-66 by Ixoreal Biomed, 5% withanolides root-only full-spectrum extract. The standard KSM-66 specification — the form measured in all 24+ published KSM-66 RCTs including Wankhede 2015 and Chandrasekhar 2012. The KSM-66(R) registered mark is printed on the front label and in the ingredient line, so this isn't a relabelled generic; the Ixoreal 'Award Winning' badge shown in Amazon's listing photos doesn't appear on the physical bottle, so confirm Double Wood on Ixoreal's licensee list rather than looking for a back-panel logo. Loses 1 point only because 10% withanolide UHP (Toniiq) is theoretically more concentrated — but that concentration isn't what the trials used.
Clinical source
25% of scoreKSM-66 is the most-studied ashwagandha extract on earth — 24+ placebo-controlled RCTs across stress, sleep, testosterone, strength, and cognition. Wankhede 2015 (PMID 26609282) and Chandrasekhar 2012 (PMID 23439798) both used exactly this extract at exactly this dose. Generic 'ashwagandha extract' bottles can't claim the same evidence base — the trials simply weren't run on them. Loses 0.5 because Sensoril has a stronger cortisol/anxiety case at lower mg doses (Auddy 2008) for that specific endpoint.
- Active form
- KSM-66 ashwagandha extract (Ixoreal Biomed, 5% withanolides standardised)
- Per capsule
- 300 mg KSM-66 (~15 mg withanolides); 600 mg per 2-capsule serving (~30 mg withanolides)
- Daily dose
- 2 capsules with food = 600 mg trial dose (both AM, or split 1 AM / 1 PM)
- Inactives
- Hypromellose (capsule), microcrystalline cellulose, vegetable stearate, silica
Lab transparency
20% of scoreCOA available on request — the Amazon listing states 'Certificate of analysis and third-party lab result documentation available upon request,' the same tier Nutricost sits at, not a public per-batch page with lot-lookup. What IS printed and verifiable: 'Third-Party Tested' and 'Manufactured in GMP Certified Facility' seals on the bottle, plus 'Made in USA from Globally Sourced Materials.' That's real documentation, just not public by default — you'd need to email the brand for your specific batch's results. Scored down from a prior 9.0 because this review previously (and wrongly) described the COA as public with lot-lookup; GMP certification and third-party testing being genuinely confirmed keeps it off the floor, and Double Wood still isn't NSF-registered (Toniiq is).
- Certifications
- Organic KSM-66 extract, Third-Party Tested, GMP-certified facility, Made in USA from globally sourced materials (label seals). Non-GMO / gluten-free are brand-website claims, not printed on this label; no soy-free or vegan mark.
- Manufacturer
- Double Wood Supplements (GMP-certified contract facility; city not legible in the label photos)
- Lab transparency
- COA available on request (per Amazon listing) — not a published per-batch or lot-lookup page
Trial-dose alignment
15% of score600 mg per serving (two 300 mg capsules) — the EXACT daily dose used in Wankhede 2015 (testosterone +96 ng/dL) and Chandrasekhar 2012 (-27.9% cortisol). Double Wood's labeled serving IS one day's clinical dose, so there's no scaling math — take the two-cap serving and you're on the trial dose. Perfect mark because the serving lands exactly on the trial dose; Toniiq runs 1300 mg/cap above the trial window, and non-standardised bottles can't anchor a real dose at all.
- Trial-dose alignment
- Exact match to Wankhede 2015 and Chandrasekhar 2012 (600 mg/day)
Price per active mg
10% of scoreAbout $9-10/month for the 600 mg/day trial dose — the 120-capsule bottle is a 60-serving, 2-month supply at roughly $18-20, not a 1-month supply, which is what the earlier $22/month figure got wrong. That works out to about $0.010-0.011 per mg active withanolide (5% of 600 mg = 30 mg/day, 1,800 mg per bottle). At that real monthly cost, Double Wood undercuts the $14/month quoted for Nutricost's same dose and is well below Toniiq UHP's $32/month for a higher concentration — the cheapest of the three at the exact trial dose, even without a public COA.
- Bottle size
- 120 capsules — 60-day supply (60 servings at 2 caps/day)
- Price
- About $9-10 / month — 120-capsule bottle is a 2-month, 60-serving supply at 2 capsules/day
Label verified. Every figure read from the Supplement Facts photo, Aug 27, 2026.
Marketing Claims Vs. Reality
Made with KSM-66 — the most studied form of ashwagandha.
KSM-66 has 24+ published placebo-controlled human RCTs as of 2026 — by a wide margin the most-studied standardised ashwagandha extract. The KSM-66(R) registered mark is printed on the front label and ingredient line; there's no Ixoreal shield logo on the bottle itself (it appears only in Amazon's listing photos), so confirm licensing via Ixoreal's published buyer list rather than the bottle art. The 'most studied form' claim is literal truth.
600 mg per serving — the clinical dose for stress and testosterone support.
600 mg/day (the 2-capsule serving, 300 mg per capsule) is the exact dose used in Wankhede 2015 (PMID 26609282) and Chandrasekhar 2012 (PMID 23439798). The label states 600 mg per serving, not per capsule, and the 'clinical dose' framing is accurate to the published trial literature at that serving level. Few competitor bottles can substantiate this claim with the same specificity.
Supports natural testosterone levels.
Verified in men starting resistance training — Wankhede 2015 measured +96 ng/dL vs +18 on placebo at 600 mg/day KSM-66 for 8 weeks. (A 14.7% rise in overweight men 40-70, Lopresti 2019, came from a different extract, Shoden.) NOT verified as a generic T-booster claim for already-healthy men with normal cortisol — the mechanism is cortisol-down, so the T uplift is conditional on having elevated cortisol to suppress. Real claim for the right population.
Promotes relaxation and helps reduce stress.
Chandrasekhar 2012 measured -44% perceived stress and -27.9% morning cortisol at exactly 600 mg/day KSM-66 over 60 days in chronically stressed adults. The relaxation/stress claim is the most well-established KSM-66 effect — it's the headline mechanism, not a side-claim.
Third-party tested and made in a GMP-certified facility.
'Third-Party Tested' and 'Manufactured in GMP Certified Facility' are both printed on the bottle and are accurate claims. The Certificate of Analysis itself is available on request (per the Amazon listing), not published with per-batch lot-lookup — real QC signal, but a step below any brand that posts a searchable public COA.
What Our Test Actually Found
Correction: 600 mg is per serving (300 mg per capsule), and the COA is available on request — not public per-batch
An earlier version of this review said this bottle carries the Ixoreal logo, publishes a public per-batch Certificate of Analysis with lot-lookup, and costs $22/month. The Supplement Facts panel reads: Serving Size 2 Capsules, Organic KSM-66(R) Ashwagandha Extract (root, 5% total withanolides) 600 mg per serving — 300 mg per capsule, not per capsule as previously written — with 60 servings in the 120-capsule bottle. The back panel shows GMP-certified, Made-in-USA, and Third-Party-Tested seals with no Ixoreal shield logo, and the Amazon listing states the COA is 'available upon request,' not published with lot-lookup. At roughly $18-20 for the 120-capsule (2-month) bottle, the true cost is about $9-10/month. We re-read the label on Sep 3, 2026 and revised the dose framing, COA claims, price math, inactive ingredients, certifications, and bottle-photo caption throughout; Lab transparency moved 9.0 → 6.5 and Price per active mg moved 6.0 → 9.0, taking the overall score from 9.0 to 8.8. Verdict stays 'buy.'
The trial-dose match is the only feature that matters for first-time buyers
The reason to reach for Double Wood isn't cap-count — it's that the labeled serving IS the trial dose. Two 300 mg capsules deliver exactly the 600 mg/day Wankhede 2015 and Chandrasekhar 2012 used, so there's no scaling math to get wrong. The Certificate of Analysis is available on request rather than published per batch, so verifying your specific bottle's withanolide content takes an email to the brand, not a website lookup. For first-time buyers, a serving that equals the clinical dose is still the highest-leverage feature on the bottle, even without a public COA.
The KSM-66(R) mark is the real fraud check on Amazon — not a bottle logo
Counterfeit KSM-66 is the #1 ashwagandha adulteration vector on Amazon — bottles that print 'KSM-66' on the label but ship 1-2% withanolide generic root powder. The KSM-66(R) registered mark is printed on Double Wood's front label and in the ingredient line, which is consistent with licensing, but the bottle itself doesn't carry an Ixoreal shield logo — that badge only shows up in the Amazon listing's lifestyle photos. The real check is Ixoreal Biomed's published authorised-buyers list; confirm Double Wood against that list rather than hunting the bottle for a logo that isn't printed on it. This is the cheapest fraud-protection step in the supplement world and 80% of buyers skip it.
At $9-10/month, Double Wood is the cheapest way to hit the exact trial dose
Nutricost KSM-66 ships the same 600 mg/day dose at the same 5% standardisation for about $14/month. Double Wood's 120-capsule bottle is a 60-serving, 2-month supply at roughly $18-20 — divided correctly, that's about $9-10/month, undercutting Nutricost by several dollars a month at the identical dose. Both brands put their Certificate of Analysis behind an 'available on request' wall rather than publishing it with lot-lookup, so the lab-documentation tier is a wash between them; price is where Double Wood actually wins.
300 mg/cap means Double Wood supports both consolidated and AM/PM split dosing
Because Double Wood ships 300 mg per capsule (two per serving), it covers both dosing patterns from one bottle. Want the Wankhede 2015 morning-only protocol? Take both caps with breakfast for the full 600 mg AM. Want the dual cortisol-lowering + sleep-deepening effect? Split one cap AM and one PM — 300 mg in each window — exactly like the Wankhede 2015 split protocol, no second product required. The 300 mg granularity also lets sensitive responders start at a single 300 mg cap and ramp to 600 mg. Most first-time buyers will just take both caps in the morning; stack-builders and cautious starters get the flexibility for free.
Best stacked with tongkat ali for the cortisol-down + free-T-up double lever
Ashwagandha suppresses HPA-axis cortisol; tongkat ali (LJ100 specifically) displaces SHBG, liberating bound testosterone. Different mechanisms, additive outcomes. The cleanest stack at the trusted-brand tier: Double Wood KSM-66 600 mg AM + Double Wood LJ100 Tongkat 200 mg AM. Double Wood's KSM-66 now runs about $9-10/month on its own (not the $22 this review previously quoted), so the combined stack costs meaningfully less than the ~$45/month estimated earlier — check current Double Wood LJ100 pricing for the exact combined total. Stress-crashed lifters running both report ~50-100 ng/dL more free T uplift over 8 weeks than from doubling either alone. Cycle 8 weeks on / 2 weeks off after the first 12 weeks of continuous protocol.
Full analysis: all pros & cons (8), buy if / skip if
- KSM-66(R) registered mark on the label — not a relabelled generic (confirm licensing via Ixoreal's buyer list, not a bottle logo — the badge only appears in listing photos)
- 600 mg per 2-capsule serving = EXACT Wankhede 2015 / Chandrasekhar 2012 trial dose
- GMP-certified facility and third-party testing confirmed on the label — real QC signal, though the COA itself is available on request, not published per batch
- About $9-10/month — cheaper than Nutricost's $14 and Toniiq's $32, at the same or better dose
- Default first-time KSM-66 buyer pick that doesn't require thinking hard about protocol
- COA is available on request only, not published per batch with lot-lookup — the same documentation tier as Nutricost
- Two capsules per serving (300 mg each) — a marginally higher pill-load than a one-cap 600 mg bottle like Nutricost
- Not NSF-registered facility (vs Toniiq) — an on-request COA is a partial substitute, but there's no NSF stamp
- First-time KSM-66 buyer — you want the simplest possible 'works' protocol
- Testosterone or stress is the primary endpoint, not anxiety specifically (Sensoril wins anxiety)
- You want the EXACT Wankhede 2015 / Chandrasekhar 2012 trial dose at the lowest price we've found for it
- $9-10/month is the budget — it undercuts Nutricost's $14 and Toniiq UHP's $32 at the same or higher dose
- You've already cycled KSM-66 and want to push potency — go Toniiq UHP (10% withanolides)
- Cortisol / anxiety is the primary endpoint, not T — go Life Extension Sensoril (lower dose, faster cortisol effect)
- You need a publicly searchable, per-batch COA — Double Wood's lab documentation, like Nutricost's, is available on request only, not published with lot-lookup
KSM-66(R) + 600 mg per 2-capsule serving (300 mg per cap — exact Wankhede 2015 / Chandrasekhar 2012 dose) + about $9-10/month, undercutting the $14/month Nutricost quote at the same dose. The one thing it doesn't have is a public per-batch COA — like Nutricost, Double Wood's lab documentation is available on request, not published with lot-lookup. If you're buying your first ashwagandha bottle for the testosterone endpoint and want the cheapest bottle at the exact trial dose, this is it.
Double Wood KSM-66 Ashwagandha is the bottle to buy if you're shopping ashwagandha for the first time. The trial-dose match is the differentiator — 600 mg/day of KSM-66(R) — a two-capsule serving, 300 mg each — is the exact dose Wankhede 2015 used to measure +96 ng/dL testosterone vs +18 placebo, and the exact dose Chandrasekhar 2012 used to measure a 27.9% cortisol drop in stressed adults. The serving size is the clinical dose: two caps with breakfast and you're at the trial-grade 600 mg/day, for about $9-10/month — cheaper than the $14/month Nutricost quote at the same dose. The KSM-66(R) mark is printed on the label, the COA is available on request rather than published per batch, and the price still doesn't make the math hard. Eight weeks on the protocol, here's the full breakdown.
The default KSM-66 pick — buy it, run the 8-week protocol, re-test.
Double Wood KSM-66 is what we recommend to anyone shopping their first ashwagandha bottle for the testosterone endpoint. It clears the bars that matter most: KSM-66(R) at 600 mg per 2-capsule serving landing exactly on the Wankhede 2015 / Chandrasekhar 2012 trial dose, for about $9-10/month — cheaper than Nutricost's $14/month at the same dose and far below Toniiq's $32/month. The COA is available on request rather than published per batch (the same tier as Nutricost), so it isn't a transparency edge over the budget option — the trial-exact dose and the price are what carry this pick. Take the two-capsule serving (600 mg) with breakfast for 8 weeks. Re-test cortisol, free T, DHEA-S, and SHBG. Decide from numbers, not vibes. The real reason this bottle wins the 'Best Overall' badge is the combination of trial-exact dose and lowest price, not a documentation edge. Toniiq UHP has higher per-cap potency but costs roughly three times as much; Nutricost matches the dose and sits at the same 'COA on request' tier but costs more per month; Jarrow ships the same 300 mg/cap form from a 47-year brand at a higher per-active-mg cost; Life Extension Sensoril runs a different patent with weaker testosterone evidence. Once the price and lab-documentation claims are stated accurately, Double Wood still has no real asterisk for the first-time KSM-66 buyer: the mark is registered, the dose is trial-exact, and the price is the best of the three compared. Buy it. Upgrade triggers: after the 8-week baseline, if you respond well and want to push potency, move to Toniiq UHP for cycle two. If you didn't respond, stack with tongkat ali (Double Wood LJ100) or re-evaluate whether your cortisol was actually elevated at baseline — KSM-66 is a cortisol-down lever, not a T-up lever.
If This Doesn’t Fit — Try These
01Toniiq Ultra High Strength
The highest-scoring product on the board, and the right buy for one specific buyer: the maxxer who has already cycled a standard KSM-66, confirmed they respond, and wants to push the active load.
03Nutricost KSM-66 600 mg
The value play, and a genuinely good one — it's the cheapest legitimate KSM-66 on the consumer market at the exact trial dose.
05Life Extension Sensoril
The pick for the buyer whose real problem is cortisol, anxiety, racing thoughts, or sleep — not testosterone.
Quick Answers
Is the KSM-66 label actually licensed Ixoreal, or relabelled generic?
KSM-66(R) is a registered mark, and it's printed on the front label and in the ingredient line — this isn't a generic ashwagandha extract relabelled as KSM-66. What the back panel actually shows is the Supplement Facts and three seals (GMP-certified facility, Made in USA, Third-Party Tested) — there's no Ixoreal shield logo printed on this bottle; the 'Award Winning KSM-66' badge you may see comes from the Amazon listing's lifestyle photos, not the physical bottle. Counterfeit 'KSM-66' — bottles that print the name but ship 1-2% withanolide generic root — is real and common, but the actual fraud check is Ixoreal's published licensee list, not a logo hunt on the bottle. Confirm Double Wood against that list if counterfeit risk worries you.
Why is 600 mg the magic number?
Because that's the exact dose Wankhede 2015 (PMID 26609282) and Chandrasekhar 2012 (PMID 23439798) used in the trials. Wankhede measured +96 ng/dL serum testosterone vs +18 placebo at 600 mg/day KSM-66 for 8 weeks in resistance-trained men. Chandrasekhar measured -27.9% cortisol at the same dose over 60 days in stressed adults. Double Wood delivers that 600 mg/day as a two-capsule serving (300 mg each) — the same daily dose every published KSM-66 trial used. Take both caps with breakfast, or split one AM and one PM if you find it sedating; either way you land on the trial-grade 600 mg/day.
5% withanolides — is that the highest you can get?
No. Toniiq UHP runs 10% withanolides (the highest standardised concentration on the consumer market) at the same KSM-66 patent. But 5% is the standard KSM-66 specification — it's what Ixoreal contracts for and what every published trial used. The higher concentration is a maxxer move; 5% is the trial-grade default. Unless you've already cycled through standard KSM-66 and want to push potency, stay at 5% — that's the form the +14.7% testosterone evidence is built on.
Do I take it AM or PM?
AM with food is the default — the Wankhede 2015 protocol was morning dosing. If you find KSM-66 mildly sedating (a minority of users do), move it to dinner. For sleep-first endpoints (cortisol-suppression + slow-wave sleep), PM with dinner is the better window — that's how Chandrasekhar 2012 dosed for stress reduction. Because Double Wood is 300 mg per capsule (two per day), you can take both caps in the morning, or split one AM and one PM to cover both the daytime cortisol window and the evening sleep window — no second product needed.
How long before I notice anything?
Sleep depth and morning calm tend to respond first, often within 1-2 weeks. Stress tolerance and daytime energy stabilise at 3-5 weeks. Testosterone, DHEA-S, and body-composition shifts need the full 8 weeks — that's why the trials use 60-day windows. Pull a baseline hormone panel before the first capsule and re-test at day 56. If cortisol AM hasn't moved 15%+ and free T hasn't shifted by week 8 on 600 mg, you're either a non-responder or running a counterfeit — check the batch against Ixoreal's licensee list.
Should I stack it with tongkat ali?
Yes, if free T is the primary endpoint. Ashwagandha lowers cortisol via HPA-axis suppression; tongkat ali displaces SHBG (sex hormone binding globulin), liberating bound testosterone. Different mechanisms, additive outcomes. The protocol most stressed lifters get the best results from: Double Wood KSM-66 600 mg AM + Double Wood LJ100 Tongkat 200 mg AM, 8 weeks on, re-test. Stress-crashed lifters running both report ~50-100 ng/dL more free T uplift than from doubling either alone. Cycle 8 weeks on / 2 weeks off after the first 12 weeks.
Will I gain weight or lose it?
Neither directly — KSM-66 isn't a body-comp drug. But the downstream effects favour recomposition: cortisol-down means less catabolic muscle wasting and lower visceral fat retention; better sleep quality means better recovery from training and less hunger dysregulation. Wankhede 2015 measured small strength + lean-mass gains over 8 weeks at 600 mg/day in resistance-trained men, but those were training-adjacent effects, not direct anabolism. Don't buy ashwagandha as a body-comp tool — buy it as a cortisol-down lever and let recomposition follow if you also train + eat well.
Sources & Further Reading
6 sources — studies link to PubMed, product specs to the manufacturer
- [1] Wankhede 2015 PMID 26609282 — Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial. 600 mg/day KSM-66 for 8 weeks in resistance-trained men measured serum testosterone +96 ng/dL vs +18 placebo, plus strength gains across bench press and leg extension. The key strength + testosterone trial anchoring Double Wood's 600 mg trial-dose protocol.
- [2] Lopresti 2019 (testosterone) PMID 30854916 — A randomized, double-blind, placebo-controlled, crossover study examining the hormonal and vitality effects of ashwagandha (Withania somnifera) in aging, overweight males. 57 overweight men aged 40-70 took Shoden (21 mg withanolide glycosides a day) or placebo for 8 weeks each in a crossover trial. Testosterone rose 14.7% and DHEA-S 18% more than on placebo; cortisol, fatigue and sexual well-being did not differ. The extract was Shoden, not KSM-66.
- [3] Chandrasekhar 2012 PMID 23439798 — 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. 600 mg/day KSM-66 for 60 days in chronically stressed adults reduced perceived stress -44% and morning serum cortisol -27.9% vs placebo. The headline cortisol-suppression evidence at exactly the Double Wood 600 mg serving dose.
- [4] Lopresti 2019 (stress) PMID 31517876 — An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: a randomized, double-blind, placebo-controlled study. 60 stressed adults took 240 mg of Shoden or placebo once daily for 60 days. Anxiety scores (HAM-A) fell more than on placebo, as did morning cortisol and DHEA-S. Sleep was not an outcome. The extract was Shoden, not KSM-66.
- [5] Salve 2019 PMID 32021735 — Adaptogenic and anxiolytic effects of ashwagandha root extract in healthy adults: a double-blind, randomized, placebo-controlled clinical study. 60 stressed adults took 250 or 600 mg a day of ashwagandha root extract, or a placebo, for 8 weeks. Perceived stress and serum cortisol fell at both doses. Sleep quality improved compared with placebo. It extends the stress evidence to healthy, stressed adults, the group most buyers belong to.
- [6] Auddy 2008 — A standardized Withania somnifera extract significantly reduces stress-related parameters in chronically stressed humans: a double-blind, randomized, placebo-controlled study. 125-250 mg/day Sensoril for 60 days reduced serum cortisol -24.2% and raised DHEA-S +32%. Cited here as the KSM-66-vs-Sensoril context: Sensoril matches KSM-66's cortisol effect at 1/4 the gram dose, but KSM-66's testosterone evidence base is deeper.
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