Research has demonstrated the ability of the supplement N-Acetyl Cysteine to help battle the flu. N-Acetyl Cysteine has several properties that make this supplement a must have in your arsenal for staying healthy during the swine flu outbreak. During the past several years, a increasing number of people have been relying on N-Acetyl Cysteine (NAC) as a simple and effective strategy for defending against influenza during normal flu seasons.