<Does anyone know anything about canker sores, in terms of cause or treatment, or anything helpful?> Hi Anju, Cancer sores are a form of herpes simplex virus. A woman at my office used Olive Leaf Extract and her sores have never returned. I would recommend that you get on the web and locate Olive Leaf Extract from East Park Research. I buy mine from Scott at 1-800-730-4139. The Upjohn Pharmaceutical Company researched Olive Leaf Extract (OLE) in 1969 and discovered that it passively rids the body of virtually every known bacteria, virus (including AIDS), parasite, fungus and yeast (candida too) invader. Then because they couldn't synthesize it (it was toxic in human blood), they shelved the research! Dr. Morton Walker has written a paperback book titled Olive Leaf Extract that is available in most large bookstores for $5.95 and contains a very detailed account of the history of OLE from ancient times. There is a four-page list in the book on the diseases researched by Upjohn from A (AIDS) to Z. Hope that this helps. Peace, Kate