Mouth ulcers – why we get them and what to do about them

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Mouth ulcers – why we get them and what to do about them

Healthylife Pharmacy24 July 2018|3 min read

Did you know recurrent attacks of mouth ulcers may be a sign of nutritional deficiencies or food sensitivities? While these painful sores in the mouth are annoying at times, they could indicate something is lacking in your diet. 

Mouth ulcers may also be triggered by stress, infection – or even if you accidentally bite your cheek. In this article, we look at what causes them and list some common mouth ulcer treatments. 

What are mouth ulcers?

A mouth ulcer happens when there has been an erosion in the mucous membrane (the delicate top layer of tissue) in the mouth or gums. These small sores can be painful – sometimes making eating and talking difficult. Unlike cold sores, mouth ulcers don’t occur on the lips and aren’t contagious. 

Many people experience mouth ulcers at some point in their lives. In some cases, they can be very large, widespread or reoccurring, and this is when you should seek advice from a healthcare professional. 

What is a canker sore?

Aphthous ulcers or canker sores are a type of recurring mouth ulcer that affects around 20% of the population. One of the most common types of mouth ulcers, they usually begin after the age of 10 and may be caused by stress, acidic or spicy foods, menstruation or accidental biting. 

Common symptoms of mouth ulcers

Common signs and symptoms of mouth ulcers include:

  • Round or oval lesions with a white or yellow centre and a red border
  • Sores that form inside the mouth, on the gums, cheeks, soft palate and on the tongue
  • Tenderness and pain
  • Loss of appetite
  • Problems with toothbrushing and chewing foods
  • Irritation by certain foods that are salty, spicy or acidic

Mouth ulcers usually heal by themselves within a few weeks. Very large mouth ulcers that extend deeper into the lining of the mouth aren't as common as small mouth ulcers but can be extremely painful and may take several weeks to heal.

Causes of mouth ulcers

There are many potential causes of mouth ulcers, so it may take some trial and error to identify the cause. To complicate matters, researchers believe that a combination of factors can be responsible for recurring mouth ulcers.

Nutritional deficiencies that may cause mouth ulcers

Research shows that if your body is lacking in B12, zinc, folate or iron, you may be more likely to suffer recurrent mouth ulcers. These are common nutritional deficiencies in the general population caused by certain medicines, poor absorption in the gut or dietary insufficiencies. B12 and iron are common deficiencies in vegetarians and vegans but can also occur in meat eaters. 

Your healthcare professional can test for these nutrients to determine what dietary supplements may be necessary.

Foods that may cause mouth ulcers

Intolerances or allergies to certain foods may result in mouth ulcers. Common foods that may be problematic include pineapple, carbonated drinks, spicy foods, cow’s milk and wheat.

How infection may cause mouth ulcers

Mouth ulcers may be triggered by microorganisms in your mouth. Helicobacter pylori has been implicated in mouth ulcers and is the same bacteria that causes peptic ulcers. 

Another discovery is that mouth ulcers may be an allergic reaction to certain bacteria in your mouth. There is also a range of other infections that may lead to mouth ulcers, including hand, foot and mouth syndrome, oral thrush and herpes simplex infection (cold sores).

Mechanical & chemical irritation

One of the most common causes of mouth ulcers is from accidental cheek biting.

Other things that can lead to mouth ulcers are injury from rubbing teeth, dental work and dental accessories (i.e. dentures and braces), overzealous brushing and sports mishaps. Chemical irritation from strong mouthwashes or toothpastes is another reason why you may suffer mouth ulcers.

Diseases that may lead to mouth ulcers

A range of other diseases may lead to mouth ulcers, including diabetes, inflammatory bowel disease, coeliac disease and other autoimmune conditions.

Other causes of mouth ulcers include:

  • Poor oral hygiene
  • Burns from eating hot food
  • Stress
  • Hormonal changes

How to treat mouth ulcers naturally

As you can see, there are numerous potential triggers for mouth ulcers.  That’s why it’s best to speak with your healthcare professional to identify the causes and seek an effective long-term treatment.  

In the meantime, here are some general ideas you can try that may help alleviate mouth ulcers.

The importance of eating a varied diet

To avoid missing out on certain nutrients, eat a diet that is varied and draws from each food group. That includes wholegrains, dairy, fresh fruit, vegetables, seafood and lean protein. If you suspect food allergies or intolerances or have specific dietary needs, this is when you might need to enlist the help of a healthcare professional.

These foods are high in vital nutrients necessary for optimal oral health and include:

Zinc – found in pepitas, oysters, meat, nuts, legumes, milk, cheese, eggs and wholegrains.

B12 –organ meats, meat and seafood products (especially red meat), fortified cereals and nutritional yeast.

Iron – meat (particularly red meat), green vegetables, beans, lentils, wholegrains and dried fruit.

Folate –fresh fruit and vegetables, fortified grains and bread, rice, beans, chickpeas and beans.

Vitamins A, C and E – fresh fruit and vegetables, wholegrains, nuts, seeds, eggs and cod liver oil.

If you suffer from recurrent mouth ulcers, it might be helpful to supplement your diet with some of these nutrients. If you do decide to take a vitamin C and zinc supplement, it may be best to take a tablet form to avoid any local irritation.

Other recommendations for treating mouth ulcers naturally 

  • Apply manuka honey topically
  • Rinse your mouth with warm, slightly salty water
  • Avoid foods that sting, i.e. spicy, salty or sour foods
  • Follow good oral hygiene practices
  • Visit your dentist regularly
  • Avoid strong commercial toothpaste and mouth rinses and opt for more natural, gentler products
  • Be gentle when you brush your teeth

If you’d like to know how to get rid of mouth ulcers so they don’t recur, make sure underlying infections or conditions are managed appropriately by visiting your healthcare professional for advice.

Related reads:


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