I don't see how Apple Cider would help canker sores, because it is acidic. What I do is I watch how much citric acid I take in. Soda is terrible! It has a very high concentration of citric acid! Milk Chocolate contains it, from what I hear, though they are not required to list it in the ingredients. I have noticed that I get them after eating chocolate, but I have to eat quite a bit of chocolate to get a sore. I have dealt with the pain of canker sores since I was a kid, often times having one right after another. I used to carry around medicines such as Kanka, only to find the stuff made them worse or made them last longer. Come to find out, I was putting citric acid directly on the sore, as many of these medications contain it! So I started with eliminating soda (I was hooked on diet pepsi at work). Bingo! I drastically reduced the number of canker sores I was getting. Next, I started watching what I was eating. I noticed that anything with citric acid in it would give me the beginnings of a canker sore within an HOUR after eating or drinking it. Then I applied some common sense to the situation, and remembered that an old cure for stomach indigestion and acid reflux was baking soda. So, whenever I eat something or drink something with citric acid in it, I immediately rinse my mouth with a mixture of baking soda and water (look on the box or on the arm and hammer website for their recommendation for using it as a mouth wash). I think the answer to canker sores is prevention, not curing it once it's in your mouth. Once it's there, you basically have to wait it out. I still get them, but only once in awhile now instead of all the time...However, when I do get one, it's my own fault now!