Ashwagandha KSM-66

Full-spectrum root extract standardized to >5% withanolides. Withanolide-A and withaferin-A are the primary bioactives. Reduces cortisol via competitive binding at glucocorticoid receptors and direct inhibition of the HPA axis ACTH response. GABAergic activity through positive allosteric modulation of GABA-A receptors, producing anxiolytic effects without benzodiazepine-class sedation. Secondary effects on thyroid hormone output (T3/T4 increase) and DHEA-S elevation.

Half-life

6-12 hours (withanolides)

Bioavailability

~45-55% (oral, root extract)

Route

oral

Evidence tier

T1 — Multiple RCTs

Optimization pillars

recovery · anti-aging

References

3 peer-reviewed

Dose ranges

Three tiers ordered by aggressiveness. Tier chips on every OPTIMIZE intervention let you filter the catalog by your evidence tolerance.

conservative

300 mg/day

Anxiolytic / cortisol management

moderate

300–600 mg/day

Standard adaptogenic dose

aggressive

600 mg 2x/day

Testosterone support / high stress

Monitoring

cortisol
dhea-s
thyroid-panel
total-testosterone
free-testosterone
alt
ast

Contraindications

hyperthyroidism
autoimmune-thyroiditis
nightshade-allergy
pregnancy

References

PMID:23439798A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root — Indian J Psychol Med, 2012
PMID:26609282Examining the effect of Withania somnifera supplementation on muscle strength and recovery — J Int Soc Sports Nutr, 2015
PMID:30854916An investigation into the stress-relieving and pharmacological actions of an ashwagandha extract — Medicine (Baltimore), 2019

Notes

KSM-66 is the ashwagandha extract that earned its reputation through clinical trials, not marketing. The cortisol reduction data is the most replicated finding. 14-28% reductions in serum cortisol across multiple RCTs. The testosterone elevation in men appears to be secondary to cortisol reduction rather than a direct androgenic effect. Important distinction. The GABAergic anxiolytic mechanism makes this a functional replacement for low-dose anxiolytics in some users, which is a significant clinical claim supported by the evidence. Cycle 8 weeks on, 2 weeks off. Continuous use can suppress thyroid in predisposed individuals. Monitor T3/T4.

This is not medical advice

Discuss with a licensed clinician before starting, stopping, or changing any compound. This page documents what the research literature describes — it is not a prescription.

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