Understanding Food Allergies and Intolerances: Symptoms, Diagnosis, and Treatment

Many people experience unpleasant reactions after eating certain foods and may think they have a food allergy. However, they may actually have a food intolerance. It's important to understand the difference between food allergies and intolerances to properly manage your condition.

What Is a Food Allergy?

A food allergy is caused by your immune system reacting to a specific food protein. When you eat the food, your body produces antibodies called immunoglobulin E (IgE), which trigger the release of chemicals like histamine. This can cause various symptoms throughout your body.

Common Food Allergies

The most common food allergies in adults include:

• Peanuts

• Tree nuts (e.g., walnuts)

• Shellfish (e.g., shrimp, crayfish, lobster, crab)

In children, the most common food allergies are:

• Eggs

• Milk

• Peanuts

Symptoms of Food Allergies

Symptoms of food allergies can range from mild to severe and may include:

• Itching in the mouth

• Vomiting, diarrhea, or abdominal pain

• Drop in blood pressure

• Hives or eczema

• Wheezing or difficulty breathing

Severe allergic reactions (anaphylaxis) can be life-threatening and require immediate medical attention.

What Is a Food Intolerance?

A food intolerance is not caused by the immune system but is usually a problem with digesting the food. For example, lactose intolerance is caused by a lack of the enzyme lactase, which is needed to digest the sugar in milk and dairy products.

Diagnosing Food Allergies and Intolerances

To diagnose a food allergy or intolerance, your doctor may:

• Ask detailed questions about your reactions and eating habits

• Recommend keeping a food diary to identify patterns

• Suggest an elimination diet to pinpoint the problematic food

• Perform skin prick tests or blood tests to measure your allergic response

• Conduct a food challenge under medical supervision

Treating Food Allergies and Intolerances

The main treatment for food allergies and intolerances is to avoid the offending food. This requires careful reading of ingredient labels and communication with restaurant staff about food preparation.

For severe allergies, you should carry an epinephrine auto-injector (e.g., EpiPen) and wear a medical alert bracelet. Mild symptoms can be treated with antihistamines or bronchodilators.

Researchers are studying allergy pills and shots as a way to desensitize people to food allergens, but these treatments are not yet proven effective.

Managing Food Allergies in Children

Milk and soy allergies are common in infants and young children. These allergies may cause colic, blood in stool, or poor growth. Breastfeeding for the first 4-6 months may help prevent allergies, but there is no conclusive evidence.

Parents and caregivers should protect children from trigger foods and have emergency plans in place. Schools should also have protocols for managing food allergies.

For more information on food allergies and intolerances, visit:

• Food Allergy Research & Education (FARE)

• American College of Allergy, Asthma & Immunology (ACAAI)

• American Academy of Allergy, Asthma & Immunology (AAAAI)