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    N-Acetyl Cysteine (NAC)

    N-acetyl cysteine (NAC) is a sulfur-containing amino acid derivative that serves as the most efficient precursor to glutathione, the body's master antioxidant. Originally developed as a pharmaceutical mucolytic agent to break down mucus in respiratory conditions, it has gained widespread use as a supplement for antioxidant support, liver protection, and detoxification.

    Research Evidence
    Protects the liver from toxin-induced damage
    Strong
    Replenishes glutathione levels and supports antioxidant defense
    Strong
    Breaks down mucus and improves respiratory symptoms
    Strong
    Supports heavy metal detoxification
    Moderate
    May reduce symptoms of mood and psychiatric disorders
    Limited
    May improve insulin sensitivity and metabolic markers
    Limited

    Expert Evidence

    16 references from 3 experts

    Safety & Cautions

    Side Effects

    • Nausea and gastrointestinal discomfort
    • Diarrhea at higher doses
    • Unpleasant sulfurous smell or taste
    • Potential blood-thinning effects
    NAC may increase bleeding risk and should be used cautiously by individuals with bleeding disorders or those taking anticoagulant medications. It is generally well-tolerated at standard doses, but long-term safety data at higher doses remains limited.
    Pairs Well With
    Price Comparison
    From $0.08/ct
    N
    Nutricost
    4.6
    180 ct

    $0.09/ct

    $15.95 total

    D
    Double WoodBest Value
    4.6
    210 ct

    $0.08/ct

    $16.96 total

    N
    NOW Foods
    4.6
    120 ct

    $0.18/ct

    $21.95 total

    N
    Nature's Fusions
    4.6
    60 ct

    $0.14/ct

    $8.49 total

    T
    Thorne
    4.7
    90 ct

    $0.37/ct

    $33.00 total