Understanding The Cause Of Canker Sores: 5 Foods to Avoid


Canker sores are a common and pesky oral health problem. They’re small ulcers that form inside the mouth and can be quite painful. It’s not uncommon to get one or two a year, and while they’re not dangerous, they can be a real nuisance. It’s believed that canker sores are caused by a combination of factors, including genetics, stress, and certain foods. In this blog post, we will explore the latter in more depth. Read on to learn about the five foods to avoid that can cause the canker sores.

What Are Canker Sores?

Canker sores are small lesions that form inside the mouth, on the tongue, on the inside of cheeks, or even at the base of the gums. These sores can prove to be highly painful and make it hard to chew or drink. These sores are not contagious, however, these can prove to be a real nuisance as these are recurrent.

There is no known cure for canker sores, but there are several treatments that can help to lessen the pain and duration of the sore. These include over-the-counter medications, home remedies, and prescription medications.

Certain foods are known to trigger canker sores. These include acidic fruits such as oranges and grapefruits, spicy foods, chocolate, coffee, and nuts. Other potential triggers include stress, hormonal changes, teeth grinding, and ill-fitting dentures. If you notice that you develop canker sores after eating certain foods or during times of stress, you may want to avoid these triggers.

Canker sores usually heal within two weeks without treatment. However, if they are large or extremely painful, your doctor may prescribe a topical cream or ointment to help speed up the healing process.

How Are Canker Sores Caused?

There are many different theories as to what causes canker sores. Some believe that they are caused by a virus, while others believe that they are an allergic reaction to certain foods. However, some common triggers have been identified. Canker sores are caused by several things, including stress, food allergies, and nutritional deficiencies.

  • Stress: One of the most common causes of canker sores is stress. When you’re under a lot of stress, your body’s immune system isn’t able to function properly, and this can lead to canker sores.
  • Food allergies: Food allergies can also cause canker sores. If you have an allergy to a certain food, your body will react by producing histamine. This histamine can cause inflammation and canker sores.
  • Nutritional deficiencies: Nutritional deficiencies are another common cause of canker sores. If you’re not getting enough vitamins and minerals, your body won’t be able to heal properly, and this can lead to canker sores.
  • Acidic foods: However, the most common cause of canker sores is acidic foods. Acidic foods include citrus fruits, tomatoes, pineapple, and strawberries. 
  • -Other causes: Other potential causes of canker sores include spicy foods, chocolate, and coffee.

Consequences of and risks associated with canker sores

Canker sores are small, painful ulcers that can form on the soft tissues in your mouth, including your gums, tongue, and the inside of your cheeks. Though they’re not contagious like cold sores, canker sores can be quite uncomfortable.

There are many potential causes of canker sores, but the most common are eating acidic or spicy foods. Foods that are high in acidity can irritate the delicate tissues in your mouth, leading to the formation of canker sores.

In addition to causing pain and discomfort, canker sores can also make it difficult to eat and talk. If you have a canker sore, you may find that hot, spicy, or salty foods are particularly painful to eat. Canker sores can also make it difficult to wear dentures or other dental appliances. If canker sores are left untreated, they can last for several weeks. In some cases, they may even lead to secondary infections, such as bacterial infections.

If you’re experiencing frequent or severe canker sores, it’s important to see a dentist or doctor to rule out any underlying medical conditions. In some cases, canker sores may be a sign of an autoimmune disease such as Crohn’s disease or celiac disease.

5 Foods That Cause Canker Sores

Canker sores are a common and painful mouth ulcer that can make eating and talking difficult. They are usually caused by a viral infection or an allergic reaction, but they can also be aggravated by certain foods.

There are a few specific foods that cause canker sores or make them worse. These include:

  1. Citrus fruits: One must avoid eating citrus fruits to prevent canker sores because they are highly acidic and can irritate the already sensitive tissue in the mouth.
  2. Spicy foods: Foods that are high in spice can also trigger canker sores. The spices can interact with the already inflamed tissue and cause further irritation.
  3. Nuts: Eating nuts can also trigger canker sores because they contain a high amount of acid. This acid can interact with the already inflamed tissue and cause further irritation.
  4. Chocolate: Chocolate contains a chemical called theobromine, which is known to trigger canker sores.
  5. Alcohol: Alcohol is also known to trigger canker sores. It can interact with the already inflamed tissue and cause further irritation.

If you suffer from canker sores, it’s best to avoid these foods as much as possible.

Of course, everyone is different, and you may find that you can tolerate some of these foods without any problems. However, if you’re prone to canker sores, it’s always best to err on the side of caution and avoid them altogether. 

How to Treat Canker Sores?

Canker sores are small, painful ulcers that can develop on the tongue, gums, or inside of the cheeks. They are often red and may have a white or yellow centre. Canker sores can be a real nuisance as they make eating and talking difficult. There is no known cure for canker sores, but there are several things you can do to ease the pain and speed up healing.

To treat a canker sore, start by rinsing your mouth with warm salt water several times a day. Maintain good oral hygiene. You can also apply a topical cream or gel to the sore to help numb the pain. If the sore is particularly large or painful, you may need to take over-the-counter pain medication. Be sure to eat soft foods and avoid spicy or acidic foods that could irritate the sore.

Usually, canker sores heal on their own within one week, or two at most. If your sore does not improve after two weeks, or if it is accompanied by a fever, you should see your doctor. However, with proper treatment, most canker sores will heal within 7-10 days.


Canker sores can be a real pain, both literally and figuratively. But by understanding what causes them and avoiding certain trigger foods, you can help prevent them from forming in the first place. Next time you’re looking to stock up on groceries, keep these five foods in mind and do your best to avoid them. Your mouth will thank you!