Glycine + NAC (GlyNAC) vs Saw Palmetto (Serenoa repens)

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

Glycine + NAC (GlyNAC)Saw Palmetto (Serenoa repens)
CategorySupplementsSupplements
Standard Dose320mg daily (standardized to 85-95% fatty acids and sterols)
TimingWith food (fat-soluble lipophilic extract). Morning or evening.
Cycle DurationMinimum 3 months to assess response; ongoing for maintenance
Evidence LevelStrongmoderate_human

Mechanism

Combination that restores glutathione synthesis. Age-related glutathione deficiency is driven by glycine and cysteine precursor depletion, not enzyme dysfunction. GlyNAC corrects oxidative stress, mitochondrial dysfunction, inflammation, and insulin resistance in older adults.

Contraindications

  • Active stomach ulcer (NAC)
  • Asthma (NAC may cause bronchospasm in rare cases)

Mechanism

Saw palmetto berry extract contains fatty acids (lauric acid, oleic acid, myristic acid) and phytosterols (beta-sitosterol) that inhibit both isoforms of 5-alpha-reductase (types I and II), reducing conversion of testosterone to dihydrotestosterone (DHT). It also exhibits anti-androgenic activity by competing with DHT at androgen receptor binding sites. Additional mechanisms include: inhibition of cyclooxygenase and 5-lipoxygenase (anti-inflammatory in prostate tissue), induction of apoptosis in prostate epithelial cells, and relaxation of bladder smooth muscle via alpha-1 adrenergic receptor antagonism.

Standard Dosing

320mg daily (standardized to 85-95% fatty acids and sterols)

Timing

With food (fat-soluble lipophilic extract). Morning or evening.

Cycle Duration

Minimum 3 months to assess response; ongoing for maintenance

Side Effects

  • Mild GI discomfort
  • Headache
  • Dizziness
  • Rare: erectile dysfunction (DHT reduction)
  • Rare: liver injury (case reports)

Contraindications

  • Pregnancy (anti-androgenic — teratogenic potential for male fetus)
  • Hormone-sensitive conditions (complex hormone modulation)
  • Children

Best Stacking Partners

Beta-SitosterolPygeumZincStinging Nettle Root (SHBG modulation)

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