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#2 in Herbal Supplements Third-Party Tested

Nutricost KSM-66 Ashwagandha 600mg

by Nutricost

"Patented KSM-66 ashwagandha root extract at the clinical dose — the most studied ashwagandha on the market"

Amazon Rating
4.5/5
Reviews
20,000+
Price Range
$14-18
Servings
60 capsules
GMP CertifiedThird-Party Tested
Our Editorial Rating
8.8
Very Good
FormCapsule
SubcategoryAshwagandha (KSM-66)
View on Amazon

Overview

Nutricost KSM-66 Ashwagandha provides 600mg of KSM-66 — the most clinically studied ashwagandha extract in the world with over 24 gold-standard clinical trials. KSM-66 is a full-spectrum root extract standardized to 5% withanolides, produced using a unique milk-based extraction process that preserves the natural balance of active compounds. Clinical studies have demonstrated KSM-66's benefits for stress reduction (cortisol lowering), anxiety relief, testosterone support in men, athletic performance, sleep quality, and cognitive function. At 600mg per capsule, each serving provides the exact dose used in most clinical studies.

Key Ingredients

IngredientAmount
KSM-66 Ashwagandha Root Extract600 mg
Withanolides5% (30 mg)

Pros & Cons

What We Like

  • KSM-66 (most studied ashwagandha extract)
  • 600mg clinical dose per capsule
  • 24+ gold-standard clinical trials
  • 5% withanolides standardization
  • 20,000+ Amazon reviews

What Could Be Better

  • 60 capsules (2-month supply)
  • May cause drowsiness in some
  • Not for pregnant/nursing women
  • Can interact with thyroid medications

Who Is This For?

Best For

  • Stress and cortisol reduction
  • Anxiety relief
  • Testosterone support (men)
  • Athletic performance enhancement

Not Ideal For

  • Pregnant or nursing women
  • Those on thyroid medications
  • Those with autoimmune conditions

Our Verdict

8.8/10 — Very Good

Nutricost KSM-66 is the best value for the most clinically validated ashwagandha extract. The 600mg dose matches the clinical studies exactly, and the KSM-66 patent ensures consistent quality. For stress, anxiety, and performance, this is the evidence-based choice.

Alternatives to Consider

No direct alternatives listed for this product yet.