I get canker sores when my nutrition is lacking. Probably want to track your food intake on something like cronometer.com and see if you are getting enough.

I get them when stressed, I also tend to get them just prior to a cold of some sort. Oddly enough, the sores, minor sinus issues, and some ear-popping are about the worst I get, even when others around me are so sick they are almost praying for a swift death.

Since I went Paleo, I'd only get a sore in my mouth after eating a low-carb burger at Carl's Junior (no bun, but possibly contaminated with gluten or other stuff while they are preparing it). So maybe it's some food that is not as clean as you think it is.

If it's the dairy, try goat/sheep fermented dairy, not cow one, and not unfermented.

My immune system reacts with cankers whenever I'm highly stressed and not getting adequate sleep. When they pop up I know I've pushed my body too hard; I take it as a sign to slow down and recharge as soon as possible. I also take vitamin C, which seems to help.

I get them when I'm under severe stress.

The only other time I get them is when I eat anything that causes abrasions inside my mouth, eg hard candy.

Stress is a likely culprit. It is quite common to get canker sores when under a greater than normal amount of stress and lack of sleep. Hormonal fluctuations can also play a part but it is not known exactly why. Your dental appliance may also be contributing, due to the rubbing, even it it doesn't appear to break the skin. Some people get canker sores due to vitamin deficiencies, particularly Vit B12, zinc, iron. There was a study done by the Ben Gurion University that showed that supplementing with Vit B12 can really help with outbreaks. You need to take 1000mcg of Vitamin b12 daily - way more than found in the average multi-vitamin. You are off to a good start by eliminating gluten and SLS toothpaste. Other common food irritants include nuts, coffee, chocolate:( and acidic foods like O.J. strawberries, citrus fruits, pineapple, raspberries, blackberries, cherries, pomegranate and cranberries, as well as overly spicy foods. For more info on causes, prevention and treatment visit this site: www.mycankersoretreatment.com

Good luck and hope you feel better soon.

Stress is an obvious culprit, but why is it that some people handle stress better than others? Genetic factors aside, it comes down to adequate nutrition.

I used to get canker sores all the time. I tried all the standard tricks -- avoiding certain foods, trying to manage stress, changing toothpastes -- but nothing worked. I found out long ago that calcium helped get rid of them, even though I used to get them back when I still ate dairy (which says something!). It helped, but it didn't solve the problem completely.

What did that, strangely, was vitamin D. After I got tested in 2010 and was found to be low, I increased my intake of vitamin D (I live in a northern climate) to 5000 IU a day. I have honestly not had a canker sore since (I've had sores from accidentally biting my lip, but since fixing my D shortage, those heal faster than my spontaneous sores ever did). This was one of the many things that made me a convert to vitamin D.

I'm not saying that's your problem, though I don't think it's a coincidence that calcium used to help me and vitamin D both raises serum calcium and increases calcium absorption. There are other things that can make a person more susceptible to canker sores. B-vitamin deficiency and iron deficiency (which often gets missed) are all possible causes worth investigating.

One tricky aspect of a paleo diet is that it is not always easy to get enough calcium, so that would be the first thing I would look at (and along with that goes an investigation of your vitamin D status).

"Stress" is kind of a blanket explanation for problems whose objective cause isn't obvious, and it doesn't really help people because it's too inspecific and very difficult for most of us to control. Plus, many of the physical effects of stress are the result of the accelerated nutrient depletion it is known to cause, whether by inadequate diet, increased nutrient demand, or both.

But if you're well-fed (which is harder to achieve than most people think) and well-rested, then you have the tools to cope with stress. Now I can eat just about whatever I want (within the scope of a healthy and nutritious diet mostly devoid of dairy :P ) and I never get them.

Canker sores tend to form when there is too much acidity in the mouth. From sugar and acidic foods such as tomatoes and fruits (bananas are the worst for me). Try rinsing your mouth out with a magnesium-based antacid or a baking soda wash after each meal. This will help restore the natural pH of your mouth and will heal your canker sore faster.

If it's recurring in the exact same spot, you could have Aphthous stomatitis. These tend to erupt when the body is under stress and/or is low on certain B vitamins. Try taking a B-complex every day as well as gargling with an alkaline solution.

nuts are often the culprit for some, esp walnuts if I remember correctly

My mom claims that fruit that hasn't been washed properly causes them. No idea if that's true, but it's worth looking into.

I also have PCOS and when I go of my treatment (birth control) I get AWFUL canker sores, almost continuously until I go back on the BC pills (and it takes a few weeks of being back on). For me it is almost 100% linked to my hormones and PCOS. I get about 1 canker a year when on BC pills but have a whole mouth full when I change pills or discontinue. My skin gets awful when I'm off the BC pills as well.

I have had braces on for over two years. I was experiencing sores all of the sudden and it was evil! I started eating broth soups and chugging water with lemon, rinsed my mouth with sea salt alot. That helped me.