N-Acetylcystein

N-acetylcysteine (NAC) may help lessen flu symptoms and loosen mucus; evidence that it prevents infection is mixed. In one study, 79% of the placebo group versus 25% of the NAC group developed clinically apparent influenza, though another account of the study says NAC reduced symptoms but not the number of infections. 1 2

• Study finding: The reported figures were 79% with clinically apparent flu in the placebo group versus 25% in the NAC group. 3
• How it may work: NAC is described as a glutathione precursor and a mucolytic that loosens mucus, helping it drain from the lungs and nasal passages. 4
• Suggested doses discussed: For prevention, 600 mg twice daily (1,200 mg total daily); for an established cold, Huberman described taking 900 mg three times daily. 5
• Availability: NAC was described as available over the counter in the U.S. at the time of recording, with prior FDA efforts to remove it from over-the-counter sales discussed. 6