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KSM-66 Ashwagandha Supplement

$ 19.95

KSM-66, an organic, root-only ashwagandha extract standardized to 5% withanolides, supporting a healthy stress response, emotional balance, and focus.* Every batch tested. Third-party tests by ISO/IEC 17025 accredited labs. COAs published openly.
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Description

Ashwagandha (Withania somnifera) has a long history of traditional use as an adaptogenic herb. Double Wood's KSM-66 is an organic, root-only extract, not root and leaf combined, standardized to 5% withanolides, the compounds central to ashwagandha's traditional and research profile.

Double Wood's formula delivers 600mg per 2-capsule serving across 120 capsules. Every batch tested. Third-party tests by ISO/IEC 17025 accredited labs. COAs published openly.

For those building a calming evening routine, KSM-66 pairs well with Magnesium Glycinate, which supports normal muscle and nerve function alongside KSM-66's support for a healthy stress response and emotional balance.*

Benefits
  • Organic KSM-66 root-only ashwagandha extract, standardized to 5% withanolides
  • Supports a healthy stress response and emotional balance as part of a consistent daily routine*
  • Supports focus during mentally demanding periods*
  • 120 capsules at 600mg per 2-capsule serving, a two-month supply at the standard daily serving
  • Every batch tested. Third-party tests by ISO/IEC 17025 accredited labs. COAs published openly.

Directions & Dosage

Take 2 capsules (600mg) daily with or without food. Some people are sensitive to ashwagandha; consider starting with 1 capsule daily for the first week to assess tolerance before moving to the full serving. Can be taken in the morning or evening as part of a consistent daily routine. Do not exceed 4 capsules per day.

The Science Behind Organic KSM-66 Ashwagandha Root Extract (Withania somnifera, standardized to 5% withanolides)

Adaptogenic stress response support. The most consistently studied benefit of KSM-66 is its role in supporting a healthy stress response. A randomized, double-blind, placebo-controlled trial by Chandrasekhar et al. (2012) published in the Indian Journal of Psychological Medicine evaluated 600mg of KSM-66 daily in 64 adults over 60 days, with the study reporting improvements in perceived stress scores, cortisol levels, and measures of overall wellbeing in the supplemented group. This is one of the most cited ashwagandha studies in the clinical literature and used the exact KSM-66 ingredient and 600mg dose in Double Wood's formula.*

Physical performance and stamina. KSM-66 has also been studied for its role in supporting physical performance and exercise capacity. A randomized, double-blind, placebo-controlled trial by Wankhede et al. (2015) published in the Journal of the International Society of Sports Nutrition evaluated KSM-66 in healthy adults engaged in resistance training over 8 weeks, finding improvements in muscle strength and markers of muscle recovery in the supplemented group compared to placebo. This is one of the most referenced studies in the adaptogenic performance category.*

View Latest Test Results

Third-party tested for quality and purity

This production lot was tested for KSM-66 ashwagandha extract and withanolide content, capsule quality, heavy metals, and microbial quality

Test Claim or Limit Result
Potency
Organic KSM-66® Ashwagandha Extract 540-750 mg 672.4 mg
Withanolides 27-37.5 mg 33.62 mg
Physical Testing
Capsule Weight 529-557 mg 543 mg
Disintegration Time NMT 30 minutes Passed
Heavy Metals
Arsenic <10 mcg/serving <0.000 mcg/serving
Cadmium <4.1 mcg/serving 0.012 mcg/serving
Lead <0.5 mcg/serving 0.081 mcg/serving
Mercury <0.3 mcg/serving <0.000 mcg/serving
Microbial Testing
Total Plate Count <10,000 cfu/g Pass
Total Yeast & Mold Count <1,000 cfu/g Pass
E. coli Absent Pass
Salmonella spp. Absent Pass
Staphylococcus aureus Absent Pass

Lot: 2523201Manufactured: 09/2025

Lab: Brand Nutraceuticals, Inc.

View Certificate of Analysis (PDF)

See the original Certificate of Analysis for complete testing details, methods, and laboratory documentation.
View Certificate of Analysis View Third Party Test Results
Identity, potency, and contaminants verified per batch Identity, potency, and contaminants verified per batch
Manufactured in an FDA-registered cGMP facility Manufactured in an FDA-registered cGMP facility
Manufactured in the USA from Globally Sourced Materials Manufactured in the USA from Globally Sourced Materials

Benefits

  • Supports cortisol regulation and stress resilience — KSM-66 has been shown in double-blind clinical studies to reduce serum cortisol by up to 27% in adults under chronic stress, supporting emotional balance without sedation.
  • Supports cognitive function and memory — Withanolides in KSM-66 appear to support acetylcholine signaling and may promote neuroplasticity, with trials showing improvements in memory recall, processing speed, and executive function.
  • Supports physical performance and recovery — Multiple clinical trials show KSM-66 may support muscle strength, VO2 max, and testosterone levels in resistance-trained adults, making it relevant for both mental and physical performance goals.
Benefits

Organic KSM-66 Ashwagandha Root Extract (Withania somnifera, standardized to 5% withanolides)

KSM-66 is a patented, organic, full-spectrum ashwagandha extract produced from the root of Withania somnifera, standardized to 5% withanolides. Withanolides are steroidal lactones specific to the Withania genus and are the primary compounds of traditional and research interest in ashwagandha.* Double Wood's formula delivers 600mg per 2-capsule serving, manufactured in the USA. Every batch tested for purity, potency, heavy metals, and microbial safety. Third-party tests by ISO/IEC 17025 accredited labs. COAs published openly.

Organic KSM-66 Ashwagandha Root Extract (Withania somnifera, standardized to 5% withanolides)

What Customers Are Saying

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Supplement Facts

Pairs well with

Powerful alone, stronger together. KSM-66 Ashwagandha Supplement delivers targeted support on its own, but combining it with complementary ingredients can help create a more holistic and balanced approach to wellness.

Frequently Asked Questions

What is the difference between organic KSM-66 and generic ashwagandha?

KSM-66 is an organic, standardized root-only extract with consistent potency, verified to 5% withanolides. It differs from other forms that may use leaves, unstandardized ratios, or non-organic sourcing.

What exactly are withanolides and why does standardization matter?

Withanolides are steroidal lactones found in the genus Withania and are the primary compounds of interest in ashwagandha. Standardization to 5% ensures every batch of KSM-66 contains a consistent, verified concentration of these compounds.

When is the best time to take KSM-66 Ashwagandha, and does timing matter?

Both morning and evening use are common. Morning use is a natural fit for those focused on daytime stress resilience, while evening use is a common choice for those winding down. Taking it at the same time each day tends to produce the most consistent results.

What supplements pair best with KSM-66 Ashwagandha?

Magnesium Glycinate is the most natural evening pairing. Magnesium Glycinate supports normal muscle and nerve function, while KSM-66 supports a healthy stress response and emotional balance, together supporting a calming evening routine.*

What does the clinical research actually show about KSM-66 at 600mg?

The most cited clinical outcomes from the KSM-66 research program at 600mg daily include improvements in perceived stress scores and cortisol levels in adults over 60 days (Chandrasekhar et al., 2012), and improvements in muscle strength and markers of muscle recovery in resistance-trained adults over 8 weeks (Wankhede et al., 2015). These are among the most cited studies in the adaptogenic supplement category and both used the exact KSM-66 ingredient and dose in Double Wood's formula.*

Is KSM-66 safe for long-term daily use?

Is KSM-66 well tolerated for long-term daily use?

KSM-66 has been evaluated in multiple clinical studies for tolerability, with studies spanning 8 to 60 days at the 600mg daily dose. It is generally well tolerated for daily use at recommended serving sizes. Those managing thyroid conditions should consult their healthcare provider before use, as ashwagandha may have mild thyroid-stimulating properties. Those taking immunosuppressive or sedative medications should also consult their provider. Pregnant individuals should avoid ashwagandha, as it has traditionally been associated with uterine stimulating properties and has not been adequately studied in pregnancy.

Overall rating: 4.75 / 5 from 4 reviews.

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Reviews

"Wonderful products"

— Yoli (5/5)

"It arrived timely and well packaged, we'll see if it works properly."

— VR (5/5)

Double Wood’s KSM-66 Ashwagandha Supplement

"Double Wood's KSM-66 Ashwagandha supplement can help naturally support healthy stress levels and support physical performance. Its high concentration of root-derived withanolides makes it one of the most researched and effective Ashwagandha on the market unlike many other market brands which sell their generic formula. For optimal results, I would recommend taking 2 capsules in the morning on a daily basis. There is no reason to cycle on/off for this particular supplement. NOTE: Please always consult her healthcare provider before taking any type of supplement to your daily regimen."

— Lou (5/5)

"So far so good."

— Nikki (4/5)

Q&A

KSM-66 Ashwagandha Supplement

From

$ 19.95

Primary Benefit

Anxiety & Stress

Other Benefits

Active Lifestyle & Fitness, Men's Health

Product Form

Capsule
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