Ashwagandha (KSM-66) vs Cordyceps Militaris

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

Ashwagandha (KSM-66)Cordyceps Militaris
CategoryAdaptogensAdaptogens
Standard Dose600mg KSM-66 daily (300mg 2x/day)1000-3000mg daily (fruiting body extract) or 500-1000mg (concentrated 10:1 extract)
TimingMorning and evening with meals. Evening dose supports sleep quality via cortisol reduction.Morning or pre-workout (energizing). Avoid evening dosing.
Cycle DurationCycle 8-12 weeks on, 2-4 weeks off (to prevent adaptogenic tolerance)Cycle 8-12 weeks on, 2 weeks off, or continuous
Evidence Levelstrong_humanmoderate_human

Mechanism

Ashwagandha's primary bioactives are withanolides (particularly withaferin A and withanolide D). KSM-66 is a full-spectrum root extract standardized to >5% withanolides. It modulates the HPA axis by reducing cortisol output (20-30% reduction in trials), likely through GABAergic activity (withanolides are GABA-mimetic at GABA-A receptors) and by normalizing cortisol receptor (GR) sensitivity. It also inhibits the NMDA-induced neurotoxicity pathway, enhances DHEA-S production, promotes thyroid function (increases T4 to T3 conversion), upregulates antioxidant enzymes (SOD, catalase, glutathione peroxidase), and has demonstrated sirtuin-activating properties.

Standard Dosing

600mg KSM-66 daily (300mg 2x/day)

Timing

Morning and evening with meals. Evening dose supports sleep quality via cortisol reduction.

Cycle Duration

Cycle 8-12 weeks on, 2-4 weeks off (to prevent adaptogenic tolerance)

Side Effects

  • Drowsiness
  • GI upset
  • Thyroid hormone elevation
  • Rare: liver injury (case reports, mainly with combination products)
  • Vivid dreams
  • Increased appetite

Contraindications

  • Hyperthyroidism or Graves' disease
  • Autoimmune conditions (immunostimulatory)
  • Pregnancy (traditionally considered emmenagogue/abortifacient)
  • Nightshade sensitivity (Solanaceae family)

Best Stacking Partners

Rhodiola RoseaMagnesiumL-TheanineTongkat Ali

Mechanism

Cordyceps contains cordycepin (3'-deoxyadenosine) and adenosine, which modulate purinergic signaling. Cordycepin activates AMPK, inhibits mTOR, and modulates adenosine receptors (A1, A2A, A3). It enhances cellular ATP production by upregulating mitochondrial biogenesis genes and improving oxygen utilization efficiency. Cordyceps increases EPO production (erythropoietin) via HIF-1alpha stabilization, enhancing oxygen-carrying capacity. Beta-glucans (1,3/1,6) activate innate immune cells via Dectin-1 and complement receptor 3 (CR3). It also relaxes bronchial smooth muscle and enhances adrenal hormone production.

Standard Dosing

1000-3000mg daily (fruiting body extract) or 500-1000mg (concentrated 10:1 extract)

Timing

Morning or pre-workout (energizing). Avoid evening dosing.

Cycle Duration

Cycle 8-12 weeks on, 2 weeks off, or continuous

Side Effects

  • Mild GI upset
  • Dry mouth
  • Insomnia if taken late
  • Rare: nausea
  • Rare: allergic reaction in mold-sensitive individuals

Contraindications

  • Autoimmune conditions (immunostimulatory)
  • Bleeding disorders
  • Pre-surgery (discontinue 2 weeks prior)

Best Stacking Partners

RhodiolaBeta-AlanineBeetroot PowderCoQ10

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