Can food allergies harm your oral health?


With food allergies increasing considerably in recent decades, it’s more important than ever to know how you or a loved one with a food allergy can maintain a healthy mouth. That’s because food allergies can not only be dangerous, but they can also have consequences for your oral health. 

Approximately 1 in 10 Americans has a food allergy.1

Just a few foods cause most allergies.

A food allergy is an unusual response by your immune system to a certain food. While some allergic reactions can be mild, others can be life-threatening.

More than 170 foods have been reported to cause allergic reactions. However, just a handful of foods account for most allergies, including fish, shellfish, peanuts, eggs and cow’s milk.

People who are allergic to birch, ragweed or grass pollens can develop a cross-reaction to certain foods that usually triggers more mild and shorter responses, such as an itching sensation in the mouth. This condition is called oral allergy syndrome (OAS) or pollen-food allergy syndrome. OAS may be activated in pollen-allergic people by eating some nuts, spices and tooth-friendly raw fruits and vegetables. That’s because the proteins in these foods are similar to the allergy-causing proteins in pollen. 

It's important to check with your physician if you think you or your child has an allergy. Be sure to discuss how pollen allergies can also influence reactions to food.  


There are other conditions that can cause similar symptoms to allergies, so your physician will consider possible causes, perform appropriate tests to arrive at a diagnosis and provide a personalized plan on how to manage reactions. 

Food allergies can lead to oral issues.

Severe reactions are best managed by recognizing signs and symptoms early and using a medication called epinephrine promptly, along with a call to your physician or an emergency room visit. For mild symptoms, antihistamines can sometimes be used. Using antihistamines can cause dry mouth, which may result in tooth decay. Be sure to drink plenty of water when taking antihistamines. 


Many of the typical signs and symptoms of a food allergy occur in the mouth, including:

• Itching and tingling

• Swollen lips, face and tongue

• Swollen throat that can restrict breathing

• Difficulty breathing

• Burning sensations

• Metallic taste

• Scratchy throat

When people with food allergies eliminate certain foods from their diets, it can also deprive them of vitamins and minerals that are vital for a healthy smile. 

It’s important to replace key vitamins and minerals.

The best way to prevent an allergic reaction is to stop eating foods that cause a response. While some foods can be skipped with no consequences to your oral health, other foods require replacements for their nutritional values.

1. Allergy to cow's milk

People who are allergic to cow’s milk need to find other sources of teeth-strengthening calcium and vitamin D.

You can help replace the calcium from cow’s milk with:

• Dark green leafy vegetables like broccoli and spinach

• Soy, rice and almond milk fortified with calcium

• Other soy products

Vitamin D can be found in:

• Fatty fish

• Egg yolks

• Vitamin D-fortified orange juice and breakfast cereals

2. Allergies to fish, shellfish, peanuts and eggs

Those with allergies to fish, shellfish, peanuts and eggs may not get enough phosphorus in their diet. Phosphorous, like calcium, is important to your teeth because it protects enamel.

You get the phosphorous you need from:

• Lean cuts of beef, pork and poultry

• Beans

• Lentils

• Soy

• Whole grains

3. Oral allergy syndrome (OAS)

Talk to your physician to understand what foods may cause a reaction. If you eliminate raw fruits and vegetables from your diet, you could miss out on important nutrients like vitamin C that helps keep teeth and gums healthy.  

You might consider:

• Cooking those foods when possible to help destroy the proteins that cause OAS, but avoid boiling, which can greatly reduce the amount of vitamin C.

• Peeling fruits because most of the allergy-causing protein is in the skin.

• Eating other fruits and vegetables that don’t cause a reaction. Green leafy vegetables, strawberries and kiwis are good choices for vitamin C if you are not allergic.

Make sure to let your dentist know if you have any allergies, are suffering from adverse side effects or are taking any medication.