Calcium Alpha-Ketoglutarate (Ca-AKG) vs NAC (N-Acetyl Cysteine)

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

Calcium Alpha-Ketoglutarate (Ca-AKG)NAC (N-Acetyl Cysteine)
CategorySupplementsSupplements
Standard Dose600-1200mg daily
TimingOn empty stomach for best absorption, 30 min before meals. Split doses if >600mg.
Cycle DurationCycle 8 weeks on, 2 weeks off (to avoid potential downregulation of endogenous GSH production)
Evidence LevelModerate (healthspan), Emerging (human longevity)strong_human

Mechanism

AKG is a TCA cycle intermediate that declines with age. Supplementation reduces inflammatory cytokines, improves stem cell function, and extends healthspan in mice. Calcium salt form provides sustained release. Also supports collagen synthesis and reduces frailty markers.

Contraindications

  • Hypercalcemia
  • Kidney stones (calcium component)

Mechanism

NAC is a precursor to L-cysteine, the rate-limiting substrate for glutathione (GSH) synthesis via glutamate-cysteine ligase. It directly replenishes intracellular GSH, the master endogenous antioxidant. NAC also modulates glutamatergic neurotransmission by stimulating the cystine-glutamate antiporter (system Xc-), influencing extrasynaptic glutamate levels. Additionally, it acts as a mucolytic by cleaving disulfide bonds in mucus glycoproteins.

Standard Dosing

600-1200mg daily

Timing

On empty stomach for best absorption, 30 min before meals. Split doses if >600mg.

Cycle Duration

Cycle 8 weeks on, 2 weeks off (to avoid potential downregulation of endogenous GSH production)

Side Effects

  • Nausea
  • GI upset
  • Sulfurous odor/taste
  • Rare: skin rash
  • Potential zinc/copper chelation at very high doses

Contraindications

  • Active gastric ulcers (may increase gastric acid)
  • Asthma (rare bronchospasm with inhaled form)
  • Concurrent chemotherapy (discuss with oncologist)

Best Stacking Partners

Vitamin CSeleniumAlpha Lipoic AcidGlycineMilk Thistle

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