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    Glycine + NAC

    With meals

    Glycine and N-acetyl cysteine (NAC) are two amino acids that together provide the essential building blocks for glutathione, the body's primary endogenous antioxidant. Glutathione production naturally declines with aging, particularly after midlife, and supplementing with its direct precursors can help restore levels more effectively than taking glutathione itself, which is poorly absorbed orally. This combination has emerged from clinical research on aging biology and is increasingly studied for its effects on oxidative stress and mitochondrial health.

    Brad Stanfield
    Brad StanfieldTakes it
    Research Evidence
    Reduces markers of oxidative stress
    Moderate
    Restores glutathione levels in older adults
    Moderate
    May improve markers associated with age-related decline
    Limited
    Provides glutathione precursors more effectively than oral glutathione
    Moderate
    Supports mitochondrial function in aging
    Limited
    Source: Examine.com

    Expert Evidence

    4 references from 1 expert

    “From the age of 45 I'd consider taking a Glycine and neck supplement of about 1 G.”

    The Only Supplements That ACTUALLY Work

    14:52
    2026
    2024
    2022
    Safety & Cautions

    Side Effects

    • Nausea or GI discomfort from NAC
    • Sulfurous taste or smell from NAC
    • Mild bloating at higher doses
    • Rare headache
    This combination is generally well-tolerated at studied doses, though NAC can cause gastrointestinal upset in some individuals, particularly at higher intakes. Those on blood-thinning medications or with bleeding disorders should consult a physician before supplementing with NAC, as it may have mild anticoagulant properties.
    Pairs Well With
    Vitamin D3Omega-3 Fatty Acids (EPA)CoQ10Magnesium