Mouth ulcers: why we get them and how to alleviate them

Mouth ulcers can be very irritating and painful and make it really difficult to eat. They often kick in when you are run down and can be a good barometer to tell you when you need some better nourishment, rest and recuperation.

Also known as canker sores or aphthous ulcers, these pesky sores on the tongue or the oral cavity can sometimes be an indicator of an underlying health issue, especially if they are large, frequently occur or do not clear that easily. In this blog post, I will explore the various reasons behind why people get mouth ulcers, shedding light on some commonly known triggers, as well as other lesser-known factors.

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Physical causes of mouth ulcers

One of the most common causes of mouth ulcers is a physical injury to the lining of the mouth. This can be as straightforward as accidentally biting the inside of your cheek or can arise from wearing badly fitted braces or dentures. Rough fillings or a sharp tooth can also cause recurring irritation, resulting in mouth ulcers. The mouth’s delicate lining can easily be damaged by hot or spicy foods, overly hot drinks like coffee or tea, or even sharp food pieces such as crusty bread. Highly salted foods such as salted peanuts can also cause sores and ulcers in some people.

Food triggers for mouth ulcers

Certain foods are known to act as triggers for mouth ulcers in some people. These can include chocolate, spicy foods, coffee, peanuts, almonds, strawberries, cheese, tomatoes and wheat flour. It’s thought that these foods can cause a reaction in the immune system or in the oral mucosa that leads to ulceration in the mouth. However, this is quite individual, and not everyone who eats these foods will develop mouth ulcers. It’s worth considering a trial of 2-3 weeks avoiding these foods to see if you find any difference, especially if you eat them very often or you have a hunch that they irritate your mouth.

Nutrient deficiencies and mouth ulcers

Deficiencies in certain nutrients such as B vitamins, zinc and iron can also contribute to getting mouth ulcers easily. These nutrients are essential for maintaining a healthy immune system and for cell growth and repair. If levels of these key vitamins and minerals are low, it could result in the body being unable to adequately repair the mouth’s lining, leading to ulcers. You can easily test for these deficiencies through a blood test via your medical doctor and in the meantime bolster up your levels of vitamins and minerals by eating nutrient-dense foods such as liver, red meat, seafood, eggs, pulses, seeds and leafy green salad leaves and vegetables.

Sensitivity to Sodium Lauryl Sulphate

Sodium Lauryl Sulphate (SLS) is a common ingredient that is found in many toothpaste brands. It’s a detergent that is also added to shampoo, bubble bath, floor cleaner and engine degreasers. Toothpaste brands use SLS in their formulas to create the foam-effect associated with feeling squeaky-clean after using.

It’s unlikely that SLS directly causes ulcers or irritates the mouth at the relatively low concentrations in toothpaste, but since it strips away the protective mucin layer in the mouth, the effect may be simply to make the mouth more vulnerable to other irritants. Studies on SLS and mouth ulcers are mixed and not of very high quality; but there is some evidence to support switching to an SLS-free toothpaste.

I want to be clear, SLS is not a necessary ingredient and you can clean your teeth very effectively even with an SLS-free toothpaste. I have seen excellent results from switching away, both for clearing ulcers fast and avoiding recurrence, so I believe more research is needed; but above all, this is a very easy thing to try if you have problems with ulcers, as avoiding SLS could give your body a better chance to fight off ulcers.

Infections and illnesses

Infections like hand, foot and mouth disease and chicken pox can result in mouth ulcers for a few days or weeks. Hand, foot and mouth is a common childhood illness that is characterised by sores in and around the mouth and a rash on the hands and feet. Not every person gets chicken pox sores in the mouth, but many do.

Similarly, those people with a weakened immune system may be more prone to developing mouth ulcers and can often precede the onset of a viral or bacterial infection. People under extreme stress are more prone to mouth ulcers, as well as those with an autoimmune condition or undergoing treatments like chemotherapy that can suppress the immune system.

Certain gastrointestinal diseases, such as Crohn’s disease and Ulcerative colitis, are also known to make you more prone to mouth ulcers and when they go alongside, the mouth ulcers tend to be larger and last for a long time. These medical conditions can potentially cause inflammation throughout the digestive tract, which can also affect the mouth. Because they can lead to malabsorption of nutrients such as vitamin B12 and iron, this may compound the issue and make it harder to knock mouth ulcers on the head.

One indicator for Coeliac disease (an autoimmune condition from ingesting gluten) is large white mouth ulcers that do not go away easily. The mouth ulcers can often be accompanied by thinning tooth enamel and general weakening of the teeth. This is most likely because coeliac disease leads to malabsorption of nutrients in the small intestines and these symptoms are signs of nutrient deficiencies even if they eat a good diet. The mouth ulcers seem to dissipate as the gut heals and the absorption of nutrients improves.

Behçet’s disease, a rare disorder that causes blood vessel inflammation throughout your body, can also cause recurrent mouth ulcers. These persistent ulcers are often the first sign of this disease.

All of these conditions above need to be assessed and diagnosed by a medical doctor.

Natural ways to alleviate mouth ulcers

Mouth ulcers normally go away on their own quickly, unless there is an underlying medical condition, however there are a few things you can do to reduce the immediate pain and discomfort.

Salt water has antiseptic properties. Add at least a teaspoon of sea salt to a small glass of warm water. Swoosh around your mouth, gargle and spit out. Repeat 3 times a day. This is only for children who can swish, gargle and spit easily.
Ice. Hold an ice cube on to the ulcer or dissolve it in your mouth. Although this can be uncomfortable in itself, it should numb the ulcer reducing pain.
Bicarbonate of soda can reduce inflammation and balance the pH level in the mouth. Mix half a teaspoon of bicarbonate of soda in a small cup of water. Swirl the liquid around your mouth for 25 seconds and spit out. Repeat 3 times a day.
Probiotic yoghurt. As well as eating this you can rub a little bit directly on the mouth ulcer. The beneficial bacteria in the yoghurt can help rejuvenate your oral microbiome and soothe pain.
Honey has antimicrobial properties. Apply to the ulcer directly in order to reduce inflammation and support healing. Opt for active honeys like Jarrah or Manuka if possible as these contain more healing polyphenols.

Round up

There are myriad of reasons why you might be experiencing mouth ulcers, ranging from physical causes, food triggers, nutrient deficiencies, infections, illnesses, and also your brand of toothpaste stripping away your mouth’s natural defences.

If you suffer from recurrent mouth ulcers, it may be wise to seek medical advice to determine the root cause and work out an appropriate support plan. This way, you can better manage and perhaps even prevent these unwelcome oral visitors.

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