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 Optimum Health GSH+: The Best Defense Against Smoke Damage and Lung Irritation Lung glutathione and oxidative stress: implications in cigarette smoke induced airway disease American Journal of Physiology Lung Cellular and Molecular Physiology American Physiological Society Glutathione system enhancement for cardiac protection: pharmacological options against oxidative stress and ferroptosis Cell Death & Disease