Corn Allergy: Symptoms, Treatment, Support

While not as common as dairy, wheat, shellfish, egg, peanut, or other types of food allergy, knowing the different corn allergy symptoms, treatment, and support options will help you during emergency situations, whether it’s you or someone you know has it.

What is corn allergy?

Corn allergy is an abnormal immune system response to corn or its by-products such as cornstarch or high fructose corn syrup. It arises from an individual’s inability to fully absorb the corn protein zein . Some people’s digestive systems have difficulty breaking down this primary protein. 

Corn allergy is very rare. One doctor in North America said he encountered his first case after 38 years of practice. 

If you have eczema, hives, hay fever, asthma or another food allergy, you may have a higher risk of getting a corn allergy. A family history of corn allergy or existing pollen allergy also puts you at an increased risk of developing corn allergy. 

What are the symptoms of corn allergy?

Symptoms of corn allergy typically manifest within minutes up to two hours of consuming food products made with corn. These symptoms include:

  • Hives or corn allergy rash
  • Sneezing
  • Nausea
  • Sinusitis or sinus headache
  • Asthma
  • Aching leg, neck, or back muscles
  • Stiff and inflamed joints 
  • Low energy levels 

In severe cases, corn allergy can cause anaphylaxis, a life-threatening allergic reaction. Its symptoms include:

  • Confusion
  • Anxiety
  • Itchy skin
  • Swollen mouth and throat
  • Abdominal pain
  • Slurred speech
  • Rash
  • Coughing
  • Swollen face
  • Breathing and swallowing difficulties
  • Wheezing
  • Low pulse

Anaphylaxis can result in loss of consciousness or death. Seek medical attention immediately if you experience any of its symptoms. 

Corn allergy diagnosis 

If you suspect you have corn allergy, your physician will ask you to take one of the following tests:  

  • Skin/prick test: Your doctor will place one drop of a solution containing corn on your arm or back. Next, he will prick or scratch that area so a small amount of the solution can seep into your skin. The sensation feels like a fingernail scratch; it won’t make you bleed. 

If a bump emerges on that spot where your doctor pricked or scratched you, it means you have corn allergy. 

  • Elimination diet: Your physician will ask you to avoid corn and other corn products for two to four weeks. During that period, he or she will monitor your symptoms to check for improvements. 

After the two- to four-week period has passed, your doctor will ask you to consume corn again to see if your corn allergy symptoms will manifest. If you’ve had a severe allergic reaction to corn in the past, your doctor may ask you to eat corn in his clinic as a precautionary measure.

If your findings remain inconclusive, your doctor may ask you to undergo further testing. These include:

  • Analysis for antibodies to corn protein
  • Fecal analysis for dysbiosis
  • Digestive system ultrasound
  • Blood test 

Corn allergy management, treatment & support

Taking preventive measures such as avoiding food sources with corn, reading ingredient labels carefully, and modifying your diet will also go a long way in lowering your risk for a sudden corn allergy attack. 

1. Medical treatment for corn allergy

If you’re manifesting symptoms of anaphylaxis—which is an emergency situation—call 000 for an ambulance immediately.

2. Avoid food sources with corn.

If you want to prevent triggering your corn allergy symptoms, you need to avoid consuming corn and its by-products. Do not eat any food source with the word “corn” in it. These include:

  • Fresh corn
  • Canned/frozen corn
  • Corn flour
  • Corn flakes
  • Corn oil
  • Corn meal
  • Cornstarch
  • Corn syrup
  • Corn sugars
  • Popcorn

Unfortunately, there are many common food products that potentially have corn. If you’re not aware or careful, you may be stocking up on these foods that may have corn. These include:

  • Aspirin
  • Bacon
  • Candy
  • Canned beets
  • Chili
  • Chop suey
  • Dates
  • Fried foods
  • Ham
  • Instant coffee/tea
  • Liquor 
  • Ketchup
  • Peas and beans
  • Salad dressing
  • Sausages
  • Soups

The best way to avoid purchasing foods with corn is to select fresh foods such as fruits, vegetables, whole grains (brown rice, quinoa, etc.), lean protein sources (fish, poultry, beef, etc.), beans, and lentils. Avoid processed and packaged foods as much as possible. 

3. Read ingredient labels.

Preventing food allergy attacks requires vigilance. You need to learn to become a smart and savvy consumer by reading ingredient labels carefully whenever you do grocery shopping. 

Refrain from buying foods with the words “corn,” “corn flour,” “corn syrup,” “hominy,” “masa,” or “maize” on the ingredient label. Other ingredients which may indicate the presence of corn include:

  • Caramel
  • Dextrose
  • Dextrin
  • Fructose
  • Malt syrup
  • Modified food starch and vinegar 

4. Modify your diet.

Your nutritionist or dietitian can help you formulate a meal plan which will help prevent your corn allergy attack and still meet your unique nutrition requirements. Preparing your food at home is the best way to monitor the ingredients in the foods you consume.

Using alternative ingredients can help you enjoy consuming the foods you love and give you peace of mind. For instance, you can use brown rice syrup for your sweets instead of corn syrup. 

If you used corn flour for your sauce and gravy thickeners in the past, switching to arrowroot starch or tapioca flour should work. You can also combine either of these two alternatives with wheat flour to produce cake flour. 

Your nutritionist or dietitian can educate you about the other ingredients that you can swap for corn-based products.

Need our help? 

If you need professional dietary advice to manage your corn allergy symptoms, you can reach out to one of our qualified nutritionists or dietitians. Call us at (07) 3071-7405 between 8am and 6pm on weekdays. Alternatively, you can send us an enquiry and we will get back to you as soon as possible.