Strengthens the mucosal lining of the stomach Zinc & l-carnosine chelated to survive stomach acid Supports microbial balance in the stomach PepZin GI is a combination of the mineral zinc and the amino peptide L-carnosine that provides protection to all areas of the stomach. The lining of the stomach is protected from its own caustic gastric juices by a thin layer of gel-like mucus. Evidence suggests that the combination of ingredients in PepZin GI isn’t easily broken down by these harsh gastric juices, so it is able to strengthen the mucosal barrier by adhering to the stomach wall.