Q. I frequently get canker sores in my mouth. It hurts to eat when I have one. But I wonder, is there something I’m eating that could be causing them?
A. No one is quite sure what causes canker sores (known in med-speak as recurrent aphthous stomatitis.) Some potential triggers, or factors thought to exacerbate the mouth ulcers, include smoking, stress, and abrasions or local trauma to the mouth area. What’s in a diet — or missing from it — has also been investigated because the canker sores might be indications of a person’s low levels, or deficiencies, in certain vitamins. Several research studies have linked vitamin B12 and related folate and iron to canker sores.
One 2002 study in the Journal of the European Academy of Dermatology and Venerology measured nutrient levels in the blood of 61 adults, including 35 men and women who had suffered from canker sores at least three times in the past year or more. While there seemed to be a trend of lower iron and folic acid levels in those who had canker sores compared to healthy subjects who did not, these numbers were not statistically different. So while the levels seemed lower, the fact that this was a small study may have masked the true differences, if there were any.
On the other hand, levels of vitamin B12 in the blood of those with canker sores were significantly different than those of healthy subjects. This suggests that low levels of B12 in the blood, or deficiencies, may play a role in getting canker sores. Of course, this study doesn’t prove that people low in vitamin B12 will get canker sores, it only shows that people who had canker sores tended to have low levels of vitamin B12 in their blood.
Another study investigated the hypothesis in a slightly different way. Researchers at the University of Connecticut, who published their study in the Journal of Oral Pathology & Medicine, looked at 100 subjects who had suffered from at least three bouts of canker sores in the past year. The study participants filled out a diet history questionnaire which asks people to estimate how much and how often they ate 124 different types of foods over the past year. None of the subjects had taken any vitamin supplements for three months or longer.
Dietary software then analyzed the information to estimate the average daily intakes of certain vitamins obtained from what they ate. These scores were compared to similar data on over 9,000 subjects from a nationally-representative database known as NHANES (the National Health and Nutrition Examination Survey). The comparison was used to assess the nutrient intakes of those with canker sores compared to a typical sample of healthy adults. Results showed that those people with canker sores actually ate lower amounts of vitamins B12 and folate than average. While blood tests were not performed in this study, one might assume that eating lower levels meant that the participants were also low, or perhaps even deficient, in the nutrients.
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Again, this study did not prove that taking in less B12 and folate through food led to canker sores, but it did show an association between poor levels of these nutrients in the diet and the occurrence of mouth ulcers. To really prove cause and effect, researchers would have to take two groups of subjects and control their nutrient intake for a period of time. One group would have to be fed a normal diet with adequate levels of all nutrients. Another group would have to be fed a diet that was low or deficient in certain nutrients such as B12. After a period of time, if those following the deficient diet started getting canker sores, it could be shown that the deficiency led to the effect. Of course, this kind of study might be unethical — to knowingly give people a diet that was missing a nutrient they needed. Such a study might not get approved from an Institutional Review Board (IRB).
So, for now, we can only get an idea that B12, and perhaps other nutrients play a role in getting canker sores, without ever really knowing, or being able to prove it, for sure.
But if you do get them, could supplementing with B12 and other B vitamins, like folic acid, help? Possibly, and it’s worth a try. A few early studies found that supplementing with these vitamins did help reduce the reoccurrence of canker sores.
Foods that you can consume that are high in vitamin B12 include meat, eggs and supplemented milk and other dairy products. Vegans can meet their needs with multi-vitamins or B12 supplements, as well as soy milks and soy yogurts that are supplemented. Some mushrooms may also provide B12. A 2009 study in the Journal of Agricultural and Food Chemistry found that white button mushrooms contained the vitamin.
Foods high in folate include all fruits and vegetables, especially spinach, broccoli, green peas, tomato juice avocados, oranges and all kinds of beans including lentils and chick peas.
Foods that are high in iron include some meats such as steak and beef liver. Tuna and cod also contain it. But you can also get it through healthy plant foods such as all types of beans (kidney, navy and chickpeas, for example) as well as oatmeal, tortillas, spinach broccoli, tomato juice, raisins, sunflower seeds, tofu, parsley and artichokes.
Find More on MSN Health:
- Foods You Should Be Eating for Your Best Body — Inside and Out
- 24-Hour Pharmacist: Answers to Your Medication Questions
- What a Healthy Smile Says About Your Health
- Bing Search: Canker Sore Remedies for Children
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