Canker Sore treatment and prevention
June 24 2016 by
Ray Sahelian, M.D.

Canker sores are painful blisters that often appear on the inside of the cheeks or lips, under the tongue, or on the gums. They affect people most frequently during their teenage years and into their 20s, and tend to affect women more than men. Up to 15 percent of the population may get them.

Canker sore cause, why they occur
Stress, genetics, menstrual cycles, poor diet or food allergies may trigger canker sores in some people. Food allergies or sensitivities include chocolate, tomatoes, and nuts. Common fruits include lemons, oranges, pineapples, apples, figs, and strawberries. In some cases celiac disease could be a cause.

Prevention and treatment
Stay away from toothpastes and mouthwashes that contain irritating ingredients.
Avoid chewing gum and very hard, crunchy or spicy food.
Keep your mouth clean by flossing regularly and brushing after every meal.
Bee propolis could offer some benefit.
See aphthous stomatitis for additional information and suggestions.

I am not sure if baking soda is of benefit or not.

Smoking cigarettes
Interestingly, those who are heavy smokers have fewer eruptions, perhaps due to immune system downregulation?

Questions
I am unable to take any amount of vitamin C or I break out in severe cold sores. It's problematic when buying formulations of different products as almost all contain some amounts of Vitamin C. Do you know why or have an opinion as to why vitamin C causes this to occur? I also have to avoid all foods high in vitamin C (I can have some but not a lot) and the kick is - I'm extremely healthy and have healthy skin! I haven't had a cold or flu in about 15 years. So, except for all the claims about what the lack of vitamin C causes, I'm not worried - should I be? I figure it's just me. But your input would be wonderful. I remember as a kid sitting in school with severe canker sores and nobody knew why. It was because I was eating oranges and nobody put two and two together at that time (I'm 57 so we're going back) and of course oranges were considered a necessary and healthy part of our diets.
   Canker sores may not necessarily be due to vitamin C, but other substances within certain foods that may cause this immune reaction. Common food allergies or sensitivities that my cause canker sores in some individuals include chocolate, tomatoes, nuts, citrus fruits, and berries.