NAC for colds

NAC may help reduce flu symptoms and loosen mucus during a cold, but the evidence for prevention is limited and more randomized controlled trials are needed.

• Study finding: In one study, clinically apparent influenza occurred in 25% of people taking NAC versus 79% of placebo recipients. 1 2
• Doses described: For prevention, Huberman mentioned 1,200 mg daily, split into two 600 mg doses. For an existing cold, he described taking 900 mg three times daily. 3
• How it may help: NAC is a glutathione precursor and a mucolytic, thinning mucus to ease congestion. Huberman preferred it to some decongestants because those can cause rebound congestion when they wear off. 4 5
• Timing: Avoid taking it close to bedtime; increased mucus flow and post-nasal drip disrupted Huberman’s sleep. 6
• Availability: At the time of recording, Huberman said NAC was legally available over the counter in the United States. 7