NAC is a great supplement. It's awesome stuff to support healthy lungs. NAC is a known mucolytic. That is a fancy term meaning breaking up mucus. Now, research does show that NAC Amazon.com: Powerful Lung Detox & Cleanse Mullein, Chlorophyll, Zinc Respiratory Support with Glutathione for Smokers & Vapors Easy Breathing by NDCO : Health & Household Disturbances of the Lung Glutathione System in Adult Guinea Pigs Following Neonatal Vitamin C or Cysteine Deficiency Full article: Role of glutathione in immunity and inflammation in the lung Increase in Extracellular Glutathione Peroxidase in Plasma and Lungs of Mice Exposed to Hyperoxia Pediatric Research