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KSM-66 Ashwagandha

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KSM-66 Ashwagandha. Root-only standardized ashwagandha extract — the most-studied form for stress and T-support.

How it works. Standardized to ≥5% withanolides from root only (no leaf). Modulates HPA axis and GABAergic tone.

What the research supports. 2 graded claims. Strongest: Lowers cortisol ~28% in chronically stressed adults (moderate).

How much to take. Typical dose: 300–600 mg. Morning or split.

Side effects and interactions. 1 medication interaction listed. Serious: Liver injury (rare case reports).

Stacking. Pairs well with Ashwagandha, L-theanine, Magnesium glycinate.

Common forms. Available as Standardized extract capsule, Liquid tincture (alcohol or glycerin), Powdered whole herb, Traditional decoction or tea.

Key studies. 9 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried KSM-66 Ashwagandha. Anecdotes are not medical advice.

KSM-66 Ashwagandha. Root-only standardized ashwagandha extract — the most-studied form for stress and T-support.

Key compound: withaferin AC28H38O6 · 470.6 g/mol

What it is

Root-only standardized ashwagandha extract — the most-studied form for stress and T-support.

Food sources

Whole dried plant material (root, leaf, flower, or aerial parts depending on the species)Standardized hydroethanolic or aqueous extract (capsule, tincture, or tea)Powdered traditional preparation used in Ayurvedic, TCM, or Western herbal practice

Goals

Cortisol ManagementTestosterone SupportAthletic PerformanceSleep & Recovery

How it works

Standardized to ≥5% withanolides from root only (no leaf). Modulates HPA axis and GABAergic tone.

Pathways

  • HPA-axis dampening
  • GABA mimetic
  • Hsp90 modulation

Effects

  • ↓cortisol ~28% in chronically stressed adults decreases
  • ↑total testosterone in overweight/aging men increases

What the research supports

Lowers cortisol ~28% in chronically stressed adultsmoderate
Raises total testosterone in overweight/aging menmoderate

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
300–600 mg
TimingMorning or split
With foodOptional
Best formMost evidence is based on the standardized extract capsule form.
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Side effects & interactions

Common side effects

  • Drowsiness

Serious

  • Liver injury (rare case reports)

Medication interactions

Thyroid hormonemoderate

May raise T4 — monitor TSH.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

Common forms

  • Standardized extract capsule
  • Liquid tincture (alcohol or glycerin)
  • Powdered whole herb
  • Traditional decoction or tea

Key studies

9 studies cited in total.

PubMed: KSM-66 Ashwagandha — Lowers cortisol ~28% in chronically stressed adults ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching KSM-66 Ashwagandha and "Lowers cortisol ~28% in chronically stressed adults". Filter by RCT, meta-analysis, or year on the results page.

PubMed: KSM-66 Ashwagandha — Raises total testosterone in overweight/aging men ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching KSM-66 Ashwagandha and "Raises total testosterone in overweight/aging men". Filter by RCT, meta-analysis, or year on the results page.

PubMed: KSM-66 Ashwagandha — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching KSM-66 Ashwagandha and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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