NAC (N-Acetylcysteine)

NAC (N-Acetylcysteine) is an acetylated form of the amino acid L-Cysteine, with much greater oral bioavailability than pure cysteine. Its main function is to serve as a precursor to glutathione — the body's primary endogenous antioxidant, produced inside cells. Glutathione protects cells against oxidative damage, heavy metals and toxins. NAC also has direct mucolytic action, being widely used in medicine to dissolve mucus in respiratory diseases.

• Primary precursor of glutathione — the body's master antioxidant
• Cellular protection against oxidative stress
• Liver health and detoxification support
• Mucolytic action — dissolves mucus in airways
• May reduce chronic inflammation
• Immune and neuroprotective support
• May improve insulin sensitivity

• •People with high oxidative stress (intense training, pollution, smoking)
• •Those seeking liver health support
• •People with chronic respiratory diseases (bronchitis, COPD)
• •High-intensity athletes for recovery and cell protection
• •People who consume alcohol regularly
• •Those seeking broad antioxidant support

600mg to 1,800mg per day, split into 1 to 3 doses. For sports and antioxidant purposes, 600mg to 1,200mg/day are sufficient. Higher doses (1,200–1,800mg) used in specific clinical contexts.

NAC is one of the supplements with the widest range of applications — from respiratory health to liver protection and sports support. For athletes, it is especially interesting for increasing intracellular glutathione, reducing post-workout oxidative stress. Unlike external antioxidants (vitamin C, E), NAC works from the inside out — it stimulates the body's own antioxidant production. Prefer capsules without additives. Taking away from meals improves absorption. Avoid excessive use in the immediate peri-workout — excess antioxidants may attenuate training adaptations.

NAC is widely studied in medicine for paracetamol (acetaminophen) poisoning — where it is the standard antidote for restoring hepatic glutathione. In sports context, studies show reduction of post-exercise muscle oxidative damage and improvement in inflammatory markers. Intracellular glutathione is the most important antioxidant in the body — and NAC is the most efficient way to raise its levels via oral supplementation, as glutathione itself has very low intestinal absorption.

May cause nausea, vomiting and diarrhea at high doses or on an empty stomach. Sulfur odor is common (characteristic of cysteine). At very high doses it may have a paradoxical pro-oxidant effect. Interaction with nitroglycerin and some cardiac medications — consult a doctor if on medication.