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Legion KSM-66® Ashwagandha Ingredient (600 milligrams per serving)

KSM-66® Ashwagandha Extract (600 milligrams per serving)

Ashwagandha root extract is an herb that’s been a cornerstone of Ayurvedic medicine for centuries. It’s derived from the ashwagandha plant, also known as Withania somnifera, which grows throughout India, Africa, and the Middle East.

KSM-66® ashwagandha extract is a patented form of ashwagandha that’s standardized to contain 5% withanolides, the bioactive compounds in the plant thought to be responsible for most of its benefits.

Although all ashwagandha supplements contain some withanolides, their concentration can range from 1% to over 35% depending on how the plants are grown, processed, stored, and other factors.[7][8]

Therefore, if an ashwagandha supplement doesn’t specify its withanolide concentration, it may contain too little (ineffective dose) or too much (extreme dose).

What’s more, the source of withanolides matters as well. While KSM-66® is made only from the root of the ashwagandha plant, many manufacturers cut corners by using leaves of the plant instead.

While there isn’t direct evidence this is harmful, most scientific research on ashwagandha has studied the effects of consuming the root, not the leaves.

All this is why KSM-66® is considered the gold standard for ashwagandha root extract, and particularly for use in scientific research—KSM-66® has been tested in 24 clinical trials, more than any other type of ashwagandha supplement.[9]

Research shows that supplementation with KSM-66® ashwagandha root extract . . .

The clinically effective dose of KSM-66® ashwagandha root extract is between 100 and 600 milligrams, though most research shows 600 milligrams is superior to lower doses.

Caffeine

No Artificial Food Dyes, Fillers, or Other Unnecessary Junk

Artificial food dyes and fillers may not be as dangerous as some people claim, but studies show they can cause negative effects in some people, including gastrointestinal toxicity and behavioral disorders.[29][30][31][32][33]

That’s why we use natural coloring derived from fruits and other foods as well as naturally derived ingredients for enhancing shelf life and facilitating the manufacturing process.

No Artificial Food Dyes, Fillers, or Other Unnecessary Junk

Lab-Tested for Purity and Accuracy

KSM-66® ashwagandha is lab-tested for purity and accuracy and certified to meet or exceed FDA and WADA safety guidelines.[34]

Lab Tested for Potency & Purity

Made in the USA with Globally Sourced Ingredients

If you want to ensure the supplements you’re swallowing every day are safe and effective, you want to buy from a company that:

  1. Sources ingredients from premium suppliers around the world (great supplements require great raw materials)
  2. Tests all products for purity and accuracy in accredited laboratories (to conclusively verify safety and efficacy)
  3. Manufactures in America, which has some of the strictest regulations in the world

And that’s exactly what we do here at Legion.

Ashwagandha Certificate of Analysis

See how Legion KSM-66® Ashwagandha compares to the rest.

  • Active Ingredient Per Serving
  • Clinically Effective Ingredient & Dose
  • KSM-66® Ashwagandha
  • Third-Party Lab Tested
  • Labdoor™ Certified Brand
  • Price Per Serving
  • Price Per Gram
  • Legion
    KSM-66®
    Ashwagandha

    Legion KSM-66® Ashwagandha
  • 600 mg
    per serving
  • true
  • true
  • true
  • true
  • GNC Herbal Plus
    Ashwagandha

    GNC Herbal Plus Ashwagandha
  • 600 mg
    per serving
  • true
  • true
  • questionable
  • false
  • $0.83
  • $1.39
  • Pure Encapsulations
    Ashwagandha

    Pure Encapsulations Ashwagandha
  • 500 mg
    per serving
  • true
  • true
  • questionable
  • false
  • $0.39
  • $0.79
  • Momentous
    Ashwagandha

    Momentous Ashwagandha
  • 300 mg
    per serving
  • true
  • false
  • questionable
  • false
  • $0.42
  • $1.38

The #1 brand of naturally sweetened and flavored sports supplements.

We’ve sold over 5 million bags and bottles to over 1 million customers in 169 countries who have left us over 55,000 5-star reviews.

Science-Backed Ingredients
Clinically Effective Ingredient and Dose

The active ingredient, form, and dose in KSM-66® Ashwagandha is backed by peer-reviewed scientific research demonstrating clear benefits in healthy humans.

Total Label Transparency
Total Label Transparency

We clearly list the dose of each ingredient in KSM-66® Ashwagandha on the label—no proprietary blends or hidden ingredients—so you can verify our formulation’s validity and effectiveness.

Lab Tested
Lab-Tested for Purity and Accuracy

KSM-66® Ashwagandha is lab-tested for purity and accuracy and certified to meet or exceed FDA and WADA safety guidelines.

Natural Ingredients
No Unnecessary Junk

KSM-66® Ashwagandha contains no artificial food dyes, fillers, or other unnecessary junk.

Made in USA
Made in the USA

KSM-66® Ashwagandha is made in America with globally sourced ingredients in NSF-certified, FDA-inspected facilities that adhere to Current Good Manufacturing Practice (cGMP) standards.

100% Money-Back-Guarantee
100% Money-Back Guarantee

If you don't absolutely love KSM-66® Ashwagandha, you get a prompt and courteous refund. No forms or returns necessary.

Trusted by scientists, doctors, and everyday fitness folk alike.

  • Dr. Bill Campbell, PhD, FISSN, CSCS

    "I most value Legion's integrity. Their products are based on the ingredients and doses shown to be effective by the scientific studies, and they don't just cite research but also fund it."

    Dr. Bill Campbell, PhD, FISSN, CSCS

    Professor of Exercise Science, University of South Florida
    Chair of Scientific Advisory Board
  • Dr. Jessie Hoffman, PhD, RD, CSDH

    "I recommend Legion because they're transparent about what's in their products, they prioritize evidence-based ingredients and dosing, and they use third-party testing."

    Dr. Jessie Hoffman, PhD, RD, CSDH

    Assistant Professor of Human Nutrition, Winthrop University
    Scientific Advisory Board
  • Dr. Eugene Choi, MD

    "As a physician, I look for evidence, transparency, and consistency. Legion checks all three. I've used their products for over 7 years because their formulations reflect a level of rigor that's uncommon in this space."

    Dr. Eugene Choi, MD

    Chair of Radiology, Good Samaritan Hospital, Los Angeles
    Scientific Advisory Board
  • Dr. Katie Vasenina, PhD, CISSN

    "I trust Legion's approach because every ingredient, dose, and formulation decision is grounded in research on what actually works in real-world application, not just what looks good on a label."

    Dr. Katie Vasenina, PhD, CISSN

    Professor of Exercise Science, University of Tampa
    Lead Formulation Scientist
  • Dr. Alyssa Olenick, PhD, CISSN

    "Legion is one of the few supplement companies with transparency and integrity. You not only get what you pay for, you know what you're paying for and taking and why."

    Dr. Alyssa Olenick, PhD, CISSN

    Exercise, Metabolism, and Female Physiology Scientist
  • Andres Ayesta, MS, RD, LD

    "I've used Legion products for years. It's rare to find a company that combines high-quality supplements with evidence-backed ingredients and fully transparent formulations."

    Andres Ayesta, MS, RD, LD

    Founder of Planos Nutrition
    Scientific Advisory Board
  • Dr. Stacie Barber PT, DPT, CSCS, FRCms, USAW

    "Legion's commitment to transparency in their labeling and use of top-notch ingredients sets them apart from other supplement companies."

    Dr. Stacie Barber PT, DPT, CSCS, FRCms, USAW

    Founder of The Physio Fix
  • Dr. Kasey Jo Orvidas, PhD

    "As someone with a strong academic and research-heavy background, I feel Legion really “gets it.” I know that what I think I'm getting with their products is actually what I'm getting: ingredients and doses supported by evidence. I can buy and recommend anything from Legion without a second thought."

    Dr. Kasey Jo Orvidas, PhD

    Published Researcher and Health Coach
  • Jordan Syatt

    "Legion is a tremendous company run by people I trust and respect. The quality of their supplements is second to no one. And while I don't use many supplements, the only ones I do come from Legion."

    Jordan Syatt

    Strength and Nutrition Coach
  • Menno Henselmans, MS

    "Legion consults with nutrition experts to make honest, science-based products and then proves they're genuine with independent lab work. That's how all supplement companies should operate."

    Menno Henselmans, MS

    Founder of Bayesian Bodybuilding, Published Scientist, and Physique Coach

The actual evidence? Real reviews from verified buyers.

Frequently Asked Questions

How do I use KSM-66® Ashwagandha?
What makes KSM-66® Ashwagandha different from other KSM-66® Ashwagandha supplements on the market?
Can I take KSM-66® Ashwagandha with other Legion supplements?
A supplement I take already contains ashwagandha. Can I benefit from KSM-66® Ashwagandha?
How much ashwagandha should I take per day? How much is too much?
What type of effects should I notice?
Are there any side effects of KSM-66® Ashwagandha?
Can KSM-66® Ashwagandha be taken while pregnant or breastfeeding?
Can KSM-66® Ashwagandha be taken with medication?
Is KSM-66® Ashwagandha gluten-free? Soy-free? Dairy-free?
Is KSM-66® Ashwagandha vegetarian or vegan friendly?
What does the Prop65 warning on the label mean?

+References

Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974.

Cooley K, Szczurko O, Perri D, et al. PLoS One. 2009;4(8):e6628. Published 2009 Aug 31.↑

Effects of Ashwagandha (Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-Analysis.

Bonilla DA, Moreno Y, Gho C, Petro JL, Odriozola-Martínez A, Kreider RB. J Funct Morphol Kinesiol. 2021;6(1):20. Published 2021 Feb 11. doi:10.3390/jfmk6010020.↑

Clinical Studies – KSM-66.

https://ksm66ashwagandhaa.com/clinical-studies/. Accessed June 30, 2024.↑

Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial.

Wankhede S, Langade D, Joshi K, Sinha SR, Bhattacharyya S. Cureus. J Ayurveda Integr Med. 2012;3(4):209-214. doi:10.4103/0975-9476.104444.↑

Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclists.

Shenoy S, Chaskar U, Sandhu JS, Paadhi MM. Nutrition. 2022;103-104:111791. doi:10.1016/j.nut.2022.111791.↑

Effects of Ashwagandha (Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-Analysis.

Bonilla DA, Moreno Y, Gho C, Petro JL, Odriozola-Martínez A, Kreider RB. J Funct Morphol Kinesiol. 2021;6(1):20. Published 2021 Feb 11. doi:10.3390/jfmk6010020.↑

Effects of Ashwagandha (Withania somnifera) on VO2max: A Systematic Review and Meta-Analysis.

Pérez-Gómez J, Villafaina S, Adsuar JC, Merellano-Navarro E, Collado-Mateo D. Nutrients. 2020;12(4):1119. Published 2020 Apr 17. doi:10.3390/nu12041119.↑

A double-blind, placebo-controlled evaluation of the anxiolytic efficacy of an ethanolic extract of withania somnifera.

Andrade C, Aswath A, Chaturvedi SK, Srinivasa M, Raguram R. Indian J Psychiatry. 2000;42(3):295-301.↑

Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974.

Cooley K, Szczurko O, Perri D, et al. PLoS One. 2009;4(8):e6628. Published 2009 Aug 31. doi:10.1371/journal.pone.0006628.↑

Effects of Withania somnifera (Ashwagandha) on Stress and the Stress- Related Neuropsychiatric Disorders Anxiety, Depression, and Insomnia.

Speers AB, Cabey KA, Soumyanath A, Wright KM. Curr Neuropharmacol. 2021;19(9):1468-1495. doi:10.2174/1570159X19666210712151556.↑

Augmentation and proliferation of T lymphocytes and Th-1 cytokines by Withania somnifera in stressed mice.

Khan B, Ahmad SF, Bani S, et al. Int Immunopharmacol. 2006;6(9):1394-1403.↑

Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study.

Salve J, Pate S, Debnath K, Langade D. Cureus. 2019;11(12):e6466. Published 2019 Dec 25. doi:10.7759/cureus.6466.↑

Potential clinical applications of Ashwagandha (Withania somnifera) in medicine and neuropsychiatry.

D'Cruz M, Andrade C. Expert Rev Clin Pharmacol. 2022;15(9):1067-1080.↑

Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis.

Cheah KL, Norhayati MN, Husniati Yaacob L, Abdul Rahman R. PLoS One. 2021;16(9):e0257843. Published 2021 Sep 24. doi:10.1371/journal.pone.0257843.↑

Potential clinical applications of Ashwagandha (Withania somnifera) in medicine and neuropsychiatry.

D'Cruz M, Andrade C. Expert Rev Clin Pharmacol. 2022;15(9):1067-1080. doi:10.1080/17512433.2022.2121699.↑

Protective role of Ashwagandha leaf extract and its component withanone on scopolamine-induced changes in the brain and brain-derived cells.

Konar A, Shah N, Singh R, et al. PLoS One. 2011;6(11):e27265. doi:10.1371/journal.pone.0027265.↑

Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot Study.

Ambiye VR, Langade D, Dongre S, Aptikar P, Kulkarni M, Dongre A. Evid Based Complement Alternat Med. 2013;2013:571420. doi:10.1155/2013/571420.↑

In vivo effects of Ashwagandha (Withania somnifera) extract on the activation of lymphocytes.

Mikolai J, Erlandsen A, Murison A, et al. J Altern Complement Med. 2009;15(4):423-430. doi:10.1089/acm.2008.0215.↑

Toxicological significance of azo dye metabolism by human intestinal microbiota.

Feng J, Cerniglia CE, Chen H. Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, AR , USA. Front Biosci (Elite Ed). 2012 Jan 1;4:568-86. ↑

Artificial food dyes and attention deficit hyperactivity disorder.

Kanarek RB. Department of Psychology, Tufts University, Medford, Massachusetts, USA. Nutr Rev. 2011 Jul;69(7):385-91. ↑

Meta-analysis of attention-deficit/hyperactivity disorder or attention-deficit/hyperactivity disorder symptoms, restriction diet, and synthetic food color additives.

Nigg JT, Lewis K, Edinger T, Falk M. Oregon Health and Science University, Portland, OR, USA. J Am Acad Child Adolesc Psychiatry. 2012 Jan;51(1):86-97.e8.↑

Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial.

McCann D, Barrett A, Cooper A, Crumpler D, Dalen L, Grimshaw K, Kitchin E, Lok K, Porteous L, Prince E, Sonuga-Barke E, Warner JO, Stevenson J. School of Psychology, Department of Child Health, University of Southampton, Southampton, UK. Lancet. 2007 Nov 3;370(9598):1560-7.↑

Effect of food azo dye tartrazine on learning and memory functions in mice and rats, and the possible mechanisms involved.

Gao Y, Li C, Shen J, Yin H, An X, Jin H. Scientific and Technological College of Chemistry and Biology, Yantai Univ., Yantai, PR China. J Food Sci. 2011 Aug;76(6):T125-9.↑