The body's first line of immune defense includes physical barriers that prevent potential pathogens from entering the body. Mucus, composed of mucins (a family of glycoproteins) and salts, is an important component of this defense for the respiratory tract. Epithelial cells lining the lungs secrete mucus, trapping particles and bacteria and preventing them from entering tissues or the blood stream. Cilia, small hair-like projections on these cells, propel the mucus out of the lungs to maintain healthy respiratory function.*

N-Acetyl-l-Cysteine (NAC) is a derivative of the dietary amino acid l-cysteine. NAC has a high affinity for lung tissue, which it supports through mucolytic and antioxidant action. Disulfide bonds bind mucins together and thicken mucus. When mucus thickens, it can become difficult to expel. Due to its sulfur content, NAC is able to disrupt disulfide bonds, thinning the mucus so that it, along with the trapped particles and bacteria, are more easily expelled from the lungs. NAC is a powerful free radical scavenger and thus supports epithelial cell health and healthy cilia activity. NAC is also a precursor to the antioxidant glutathione. Supplemental NAC supports tissue levels of glutathione. Lymphocytes, specific components of the immune system, rely on glutathione to function properly. Tissues enhanced with glutathione support overall antioxidant protection and help to maintain a healthy immune response.*

A multicenter, randomized, double-blind trial with 262 participants indicated that NAC supplementation for 6 months supported upper respiratory tract and immune system health. A recent meta-analysis of 8 double-blind, placebo controlled trials provided additional support for NAC's ability to support respiratory tract health.*

Pure Encapsulations provides NAC in both 600 mg and 900 mg capsules. Pure Encapsulations also offers Nutrient 950® with NAC, providing 1000 mg NAC per serving. This formula also contains beta-carotene, zinc and vitamins C and E which provide additional immune support. *