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NAC 900
900 mg of NAC to Support Athletic Resilience*
N-acetyl-L-cysteine (NAC) to support glutathione production, which helps maintain the body's natural antioxidant defenses and post-training recovery.* NSF Certified for Sport®.
Provides 900 mg of NAC per capsule, the highest serving currently available among NSF Certified for Sport® NAC products.†
- Supports glutathione production and the body’s natural antioxidant defenses*
- Helps maintain exercise performance during strenuous training*
- May help delay normal exercise-induced fatigue during prolonged or repeated strenuous exercise*
- Helps support recovery between training sessions*
- Promotes respiratory and immune health*
Recommended Use: Take one capsule per day.
†Based on amount per serving compared to Thorne® NAC as of June 2026.
How NAC supports athletic performance and recovery*
N-acetyl-L-cysteine (NAC) is a stable form of cysteine, an amino acid your body uses to produce glutathione, one of its most important antioxidants found inside your cells.* During strenuous exercise, your body uses more energy, increasing demands on the body’s redox balance systems. By supporting glutathione production, NAC helps maintain these systems while supporting exercise performance, post-exercise recovery, respiratory health, and immune function during periods of intense physical activity.*
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