For stress relief and cortisol management, this delivers 600mg of **KSM-66 Ashwagandha** per capsule — hitting the top of the 300–600mg clinical range used in research. KSM-66 is the most studied branded ashwagandha extract, standardized to a minimum 5% withanolides, and multiple RCTs show it can reduce your perceived stress and lower cortisol levels within 8 weeks.

The formula includes 5mg of **BioPerine** (black pepper extract) to support absorption. The single-capsule serving keeps things simple, and the 60-capsule count gives you a full two-month supply at one per day.

One thing to keep in mind: ashwagandha may interact with thyroid medications and is not recommended during pregnancy. If you're taking it for sleep support, some studies used doses split between morning and evening, so a single 600mg dose may work differently than two 300mg doses spread throughout your day.

BioStacks
Nutricost

KSM-66, Ashwagandha Root Extract, 60 Capsules

1 Capsule · 60 servings

iHerbAmazon
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What it does

A combination of 2 label ingredients.

Ashwagandha

Mixed formsGrade —

Label lists Organic KSM-66 Ashwagandha Extract (600 mg). Benefit information is limited.

Black Pepper Extract

Form not confirmedGrade —

Can increase curcumin absorption; whether this improves health outcomes remains uncertain.

Stress & Mood
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Ingredients (2)

Other ingredients

Magnesium StearateLubricant

A salt of stearic acid used as a lubricant in tablet and capsule production

Silicon DioxideAnti-caking

Fine silica powder used to prevent clumping

HypromelloseCapsule

Plant-derived capsule material from cellulose

StarchBinder

Carbohydrate polymer used as a binder, filler, and disintegrant in tablets and capsules

Lab testing

How to take it

With food

Price check

$14.95

$0.25 / serving

$10$20

Cheaper than 78% of 146 ashwagandha supplements

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Sources & Scoring

Nutrient data (RDA, UL, and safety thresholds) sourced from the NIH Office of Dietary Supplements and the National Academies Dietary Reference Intakes (DRI).

This is not medical advice. Consult a healthcare provider before making changes to your supplement routine.

The score analyzes what's on the label: ingredient doses vs. studied ranges, chemical forms, evidence levels, and known interactions. It does not verify label accuracy or test for contaminants — for that, look for third-party certifications like USP or NSF.

Not medical advice. Consult your healthcare professional.

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