What Causes Food Allergies?

Food allergies occur when your immune system misinterprets food proteins as a threat to your body. As a result, your immune system triggers the release of various substances into the bloodstream, causing allergy symptoms.

Although almost any food can cause an allergic reaction, most food allergies are caused by just a few culprits. If you or your child has a food allergy or if you suspect a food allergy is causing your symptoms, scheduling a visit with an allergy specialist at Rheumatology and Allergy Institute of Connecticut, LLC, is the next best step.

Allergy and immunology specialist Reinhard Kage, MD, can help you get an accurate diagnosis. The only way to prevent an allergic reaction is to strictly avoid the food or food substance you’re allergic to. Once your diagnosis is confirmed, Dr. Kage works closely with you to ensure that your diet is safe.

Types of food allergies

Food allergies are classified based on the symptoms and when they occur.

The most common type of food allergy is IgE-mediated food allergy, which is caused by your immune system producing an antibody called immunoglobulin E (IgE). After consuming the allergen, symptoms appear within seconds or minutes. This type of allergy carries a higher risk of anaphylaxis.

Food allergies that aren't mediated by immunoglobulin E (non-IgE-mediated food allergies) are caused by other immune system cells. This type of allergy is difficult to diagnose because symptoms take longer — up to several hours — to show up.

What causes allergies?

Scientists aren’t sure what causes allergies, but genetics appears to play a significant role. If your parents have allergies of any kind, you're more likely to have them. People with immune-related conditions like asthma or eczema are also likely to have or develop allergies.

There's also some biological predisposition. It may seem unfair, but if you already have an allergy, you're more likely to develop another one. When you consider it, your immune system has already overreacted to one allergen and is producing immunoglobulin E unnecessarily, so it’s prone to have the same reaction to something else.

What foods cause allergies? 

While any food can cause an allergic reaction, most allergies are caused by the following eight foods:

• Cow’s milk
• Eggs
• Peanuts
• Tree nuts
• Fish
• Shellfish
• Wheat
• Soybeans

Fortunately, manufacturers must declare the “big 8” allergens on food labels.

The importance of an accurate diagnosis 

Not everyone who reacts to certain foods has a food allergy. Some people may believe they have food allergies because they experience itching in their mouth and throat after eating raw or uncooked fruits or vegetables, but this could be due to oral allergy syndrome, which is a reaction to pollen rather than the food itself.

There's also a distinction between food allergies and non-allergic food sensitivity. Food sensitivities and intolerances can cause symptoms such as bloating and stomach cramps, which usually appear several hours after eating. Food allergies, on the other hand, tend to happen quickly. People with a food intolerance can usually tolerate small amounts of the problematic foods. 

Celiac disease is frequently confused with wheat allergy and gluten intolerance; however, it is an autoimmune disease in which the body attacks its own cells. Gluten — a protein found in wheat, rye, and barley — causes the body to damage and destroy the lining of the small intestine.

If you suspect you or your child have a food allergy, take the proactive step and see a doctor and get tested right away. An accurate diagnosis is key.

You’re in capable hands when you visit the Rheumatology and Allergy Institute of Connecticut, LLC. Dr. Kage has extensive experience diagnosing food allergies. To get started, call our office in Manchester, Connecticut, to schedule a visit for a food allergy evaluation, or book your request online.