NAC (N-Acetyl Cysteine) vs Resveratrol

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

Mechanism

Resveratrol activates SIRT1 (the longevity sirtuin) via allosteric binding, promoting deacetylation of PGC-1alpha (mitochondrial biogenesis), FOXO3 (stress resistance), and p53 (DNA repair). It inhibits NF-kB and COX-2, reducing chronic inflammation. Resveratrol also activates AMPK independently of SIRT1 and inhibits phosphodiesterases (PDEs), raising cAMP levels. It improves endothelial function via eNOS upregulation and NO production.

Standard Dosing

250-500mg trans-resveratrol daily

Timing

Morning with a fat-containing meal. Often taken alongside NMN for synergistic sirtuin activation.

Cycle Duration

ongoing

Side Effects

• GI upset/diarrhea at high doses
• Headache
• Joint pain (rare)
• Insomnia (if taken late)

Contraindications

• Estrogen-sensitive cancers (theoretical ER agonism)
• Bleeding disorders
• Pregnancy/lactation

Best Stacking Partners