Ashwagandha (KSM-66)

adaptogens

★★★★★

Ancient Ayurvedic adaptogen. Clinically shown to reduce cortisol, improve stress resilience, and enhance sleep quality. KSM-66 is the most researched extract.

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Benefits

✓Reduces cortisol and perceived stress

✓Improves sleep quality

✓May increase testosterone in men

✓Anxiety reduction

✓Physical performance enhancement

Dosage

Typical Dose

300-600mg daily (KSM-66 extract)

Upper Limit

1,200mg daily

Timing

Evening for sleep, or split morning/evening for stress

Forms & Bioavailability

KSM-66

High — full-spectrum root extract, most clinically studied

Sensoril

High — root and leaf extract, higher withanolide content

Generic root powder

Lower — less standardised, variable potency

Side Effects

⚠Drowsiness (dose-dependent)

⚠May worsen thyroid conditions (can increase thyroid hormones)

⚠Mild digestive upset in some people

⚠Not recommended during pregnancy

Interactions

⚡Thyroid medications — may increase thyroid hormone levels

⚡Sedatives — additive drowsiness

⚡Immunosuppressants — may stimulate immune system

Research Summary

Multiple RCTs showing cortisol reduction (14-28%) and improved sleep quality. KSM-66 has the most clinical data. A 2021 systematic review of 12 trials confirmed anxiolytic and stress-reducing effects.

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The Bottom Line on Ashwagandha (KSM-66)

Ashwagandha (KSM-66) is well-researched with strong evidence supporting its primary benefits.It is most commonly used for reduces cortisol and perceived stress and improves sleep quality. As with any supplement, individual results vary. Start with the lower end of the dosage range and assess for 4-8 weeks before adjusting.

About Our Research

This profile is compiled from peer-reviewed research published on PubMed, the NIH Office of Dietary Supplements, and established nutritional science databases. Dosages reflect clinically-studied amounts from human trials where available. We update profiles as new research emerges. This is not medical advice — consult a healthcare professional before supplementing.

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Goal Guides for Ashwagandha (KSM-66)

See how Ashwagandha (KSM-66) can help with specific health goals:

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Disclaimer: This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement, especially if you have existing health conditions or take medication.