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Cold Sores, Canker Sores and Gluten

Cold Sores, Canker Sores And Gluten

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This month I write about two disorders that some might consider trivial, mere nuisances to be quickly forgotten-canker sores and cold sores. These painful and annoying eruptions may, however, be a clue that something else is amiss.
Canker sores and cold sores are both very common and frequently confused.Their presence is usually seen as a bother that is not worthy of mention by patients in my office. I typically have to inquire about them or they are not discussed. Patients ask, “Everyone gets them, don’t they?”
While they may be commonplace, if they are appearing frequently, further evaluation for underlying reasons is warranted. Ivy (name changed for privacy) came to see me several months ago because she was getting canker sores in her mouth so severe she could not eat. Newly diagnosed with non-celiac gluten sensitivity, she had heard of a correlation between canker sores and gluten. While gluten may be one trigger, Ivy was already on a gluten-free diet, so we set out to look for other possible culprits.

Canker Sores

Canker sores, known as apthous ulcers in the medical community, are round or oval lesions, usually surrounded by redness and mild swelling. They occur on the gums,inside of the cheeks,and under the tongue. They do not appear on the lips, palate or top of the tongue. You may have anywhere from one to six at a time and they typically last seven to ten days. No one knows their true cause, but there are many known triggers, including gluten for those with a gluten-related disorder.Canker sores are not contagious. They are usually infrequent, occurring once or twice a year. When canker sores occur often, it should be a red flag to you and your practitioner, and prompt further evaluation.

Canker Sores: Trigger

Common triggers for canker sores include stress, food allergies and sensitivities, hormonal changes, vitamin and mineral deficiencies (iron, folate, B12, zinc ) and sodium lauryl sulfate (found in most toothpastes). They also occur more commonly in people with celiac disease, Crohn’s diseasedermatitis herpetiformisBehcet’s Disease and gastric reflux disease. Local trauma to the area, such as accidentally biting your cheek, can also trigger the formation of a canker sore.

Canker Sores and Gluten

Canker sores occur more commonly in people with celiac disease than in the general population. In a 2004 study, five percent of patients with recurrent canker sores were found to have celiac disease. Since this is five times the rate of celiac disease in the general population, a patient with recurrent canker sores should receive prompt screening for celiac disease.
Canker sores are often a sign that someone has been exposed to gluten accidentally while maintaining an otherwise gluten-free diet. I see this frequently in my office; sores appear after a person with celiac disease has dined out. Could canker sores be a clue to cross contamination in small amounts? I have not found any medical studies about a possible correlation, as it would be difficult to research, but I hear this from my patients frequently.
Some researchers believe that the oral ulcers that occur with celiac disease may be different than the oral ulcers of apthous stomatitis/canker sores. I would argue that the patient and doctor will be unable to distinguish this difference clinically and that any patient with recurrent oral ulceration should be evaluated for celiac disease.
Do people with non-celiac gluten sensitivity (NCGSget canker sores from gluten? There is very little data on a correlation, but a study published in September 2015 found that the number of canker sores did increase when people with NCGS ate gluten.

Canker Sores: Traditional Therapies

Most canker sores resolve on their own in seven to ten, days but if they are particularly
painful or large, treatment may be needed. Mouth rinses, topical numbing medicine, vitamins (if deficient), anti-inflammatory medication or acetaminophen are used to control symptoms. Topical steroids or steroid rinses are given if symptoms are severe.

Canker Sores: Integrative Therapies

In addition to the therapies listed above, avoidance of triggers is crucial to any form of treatment for canker sores. Stress reduction techniques (meditation, exercise, breathing techniques, etc.), avoidance of food triggers (common ones are tomato, pineapple, citrus and wheat), and adequate sleep and diet (to support a healthy immune system) are all necessary. Lip balm with sunscreen is also needed if sun or wind are triggers. When canker sores do occur in spite of lifestyle modifications, deglycyrrhizinated licorice (DGL) in a pill or mouthwash form is often used. Other alternative therapies include myrrh, goldenseal, chamomile and aloe. These can be used in teas, pills, tinctures or mouthwashes.

Helping to heal

Back to my patient, Ivy. Even though Ivy was already on a gluten-free diet, we discussed the possibility of minute exposures causing symptoms. This can be a problematic issue for some people and an important point to consider even if someone does not have celiac disease. We corrected her low iron and addressed her anxiety over something that was happening at work. We also used topical chamomile tea bags and DGL capsules to alleviate symptoms. Her outbreaks have almost completely stopped.

Cold Sores

Cold sores (also called fever blisters) are caused by the herpes simplex virus. They may be preceded by tingling in the area before the tiny fluid-filled sores emerge. The sores blister and eventually break open, forming a crusty lesion. They occur on the lips and lip border and take longer to heal than canker sores-about two to four weeks. They are contagious and can reoccur throughout life once you carry the infection. Reoccurrences tend to be in the same spot, as the virus sits dormant in the nerve. They may be triggered by stress or illness and are not typically frequent occurrences. If common, they should also prompt further evaluation.

Ruby’s Story

Ruby came to see me about her digestive problems.  She had a family history of celiac disease. She was one of the few patients who voluntarily discussed her chronic problem with cold sores on her upper lip. They were painful and cosmetically unappealing to her. She wanted to know if there could be any correlation with her digestive problems. She was already on a gluten-free diet.

Cold Sores: Triggers

Cold sores derive their name from the fact that they occur more commonly when someone has a cold or illness. They appear during times of stress or low immunity, as well as after prolonged sun or wind exposure. They may also appear in correlation with the menstrual cycle. They can be associated with underlying immune disorders, which is why recurrent episodes may require further evaluation.

Cold Sores and Gluten

There is no known direct correlation with gluten. However, if someone is chronically ill or stressed from gluten exposure, cold sores may be indirectly triggered by gluten exposure.

Cold Sores: Traditional Therapies

Most cold sores will resolve with no treatment in two to four weeks. Avoiding close contact with anyone who has a cold sore is the primary means of prevention. Kissing is a common form of transmission. Decrease the risk of passing the virus on to others by avoiding touching blisters.Using sunblock and lip balm may help prevent occurrences for those triggered by sun and wind. Cool compresses and over the counter numbing medicines such as benzocaine are used for pain management.Over the counter treatments such as Abreva may be applied topically and alcohol-based formulas are used to dry out the lesion.Antiviral prescription medications may be used and shorten the course of symptoms slightly.

Cold Sores: Integrative Therapies

As with cankers sores, addressing triggers such as lack of sleep or increased

stress is vital to prevention and recovery of cold sores. When symptoms arise, lysine is an amino acid that is commonly used in an oral or topical cream to speed healing. Consumption of foods high in lysine (beans, peas and corn) can also be used as a means of prevention.  A rhubarb and sage cream or lemon balm are also used as topical remedies. Probiotics may also be beneficial to alleviating cold sores by supporting the immune system and combating the virus.

Ruby’s answer

Ruby did not have celiac disease, but was sensitive to gluten. We discussed her high stress lifestyle as well as elimination of micro-amounts of gluten. We used probiotics and a low sugar diet to support her immune system, and topical lemon balm when cold sores appeared. We also addressed her disrupted sleep. She has been free of cold sores for over 2 years now.

Pay attention to these seemingly harmless actors

If you suffer from either of these disorders, canker sores or cold sores, and they are occurring frequently, pay attention. Consider the possible causes mentioned above and if outbreaks persist, seek further evaluation from your health care provider. These small eruptions may be easily treatable or may signal an underlying disorder in need of further evaluation.


Dr. Amy

Dr. Amy Burkhart

Past columns by Dr. Burkhart:

April/May 2016: Reasons People Follow a Gluten Free Diet: 7 Types of Gluten Free Dieters 

March 2016: Ten Positive Aspects of a Celiac Disease Diagnosis

February 2016: Gluten Causes Keratosis Pilaris (a.k.a. “Chicken Skin”): Fact or Myth?

January 2016: Fingernail Changes in IBS,Gluten Disorders and Celiac Disease “A window to health”

December 2015: 20 Gluten-Free Gift Ideas: From Budget to Luxury, Sentimental to Practical & More

November 2015: Cold Sores, Canker Sores and Gluten

October 2015: Celiac Disease and Gluten Sensitivity Research: Snippets from ICDS 2015 (Part 2)

September 2015: Celiac and Gluten Sensitivity Research: Ten Snippets from ICDS 2015

July/August 2015: A New Home Test To Monitor Gluten Exposure

June 2015: Six Reasons to Test for Celiac Disease Before Starting a Gluten-Free Diet

May 2015: POTS, Celiac Disease and Gluten: An Undiscovered Connection?

February/March/April 2015: Arsenic in the Gluten-Free Diet: Facts and Tips

December 2014/ January 2015: The Microbiome and Celiac Disease: A Bacterial Connection

November 2014: Celiac disease and gluten sensitivity: The doctor-patient disconnect

October 2014: Should You Trust Gluten-Free Labels?

September 2014: Triggers for celiac disease: One possible answer

July/August 2014: Ten Tips for a Healthier Gluten-Free Diet

June 2014: Back Pain and Gluten

May 2014: Self-Diagnosis of Gluten Sensitivity: Four Alarming Trends

April 2014: Update on Restaurants and Gluten-Free Dining

March 2014: Histamine Intolerance: Could it be causing your symptoms?

February 2014: Celiac Disease and Non-Celiac Gluten Sensitivity (Reprinted with permission from Sonoma Medicine)

January 2014: Four Vitamin Toxicities on a Gluten-Free Diet

December 2013: Move Over Gluten-Free, Low FODMAP is Next

November 2013: SIBO, Gluten and IBS: What Is The Connection?

October 2013: Pesticides, Wheat and Gluten Sensitivity: What is the Connection?

September 2013: Is gluten really the culprit in gluten sensitivity?

August 2013: Clarifying the Gluten-Free Labeling Rule

June/July 2013: No such thing as Mild Celiac Disease

May 2013: Magnesium Deficiency

April 2013: Six Reasons to test for celiac disease before starting a gluten-free diet

March 2013: Why am I having migraines?

February 2013: What is fructose malabsorption?

January 2013: Educating doctors about celiac disease

December 2012: Are supplements to digest gluten safe and useful?

November 2012: Top 5 reasons for persistent symptoms after Going Gluten Free

AmyBurkhart M.D., R.D.
Please do not rely on the information on this website as an alternative to medical advice from your doctor or other professional or health care provider. If you have any specific questions about a medical matter you should consult your doctor or other professional health care provider. If you think you may be suffering from any medical condition you should seek immediate medical attention. You should never delay seeking medical advice, disregard medical advice, or discontinue medical treatment because of information on this newsletter or Dr. Burkhart’s website or social media sites.

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“I have been a patient of Dr. Amy Burkhart for several years. I suffer from Crohn’s disease and was having difficulty in my daily life. After visiting many doctors, all of whom were unable to help me, Dr. Burkhart took the time and patience to create a plan which brought me back to health. I still follow her plan to this day and have been living a normal healthy life. Dr. Burkhart listened to my symptoms along with listening to me, she took her time in preparing a plan which led me to the road for recovery. I cannot thank Dr. Burkhart enough, and I would recommend her to anyone.”

8 months ago

Stone Brewing company Stone Brewing - Napa opened recently in Napa in an historic building adjacent to the river. A great venue to enjoy life! The gluten free menu options are coming (per the manager ) but please visit and inquire about GF options. The more people who show interest and discuss cross contamination the more likely they are to get it right! Wine is available. Maybe they will even consider a GF beer! . ... See MoreSee Less