Information on the causes of food allergies and food allergy symptoms.

What are Food Allergies?

Food allergies are quite rare, affecting about 3% of adults and 6-8% of children. A food allergy is a clinically proven adverse immune response to a food. Food allergies have varying symptoms depending on the severity of the allergy. People with food allergies should always avoid trigger foods. Even mild allergies can eventually become severe, causing anaphylaxis and other serious conditions that can be fatal.

Food intolerance is far more common, affecting nearly the entire population at some point. A food intolerance is not as severe initially as an allergic reaction, but it can lead to long-term damage over time if exposure to offending foods is not reduced.

Diagnosing Food Allergies

Food allergy diagnosis starts with a detailed history of symptoms and a physical examination. During this time, your physician will ask when your symptoms began, the types of foods you ate when they started, and any other questions that can help determine if there are food allergies present.

Once a complete history is examined, there are several options for testing. Skin tests, called “scratch tests”, allow for the testing of several potential allergens at once. Small amounts of several potential allergens are introduced to the skin on the forearm or on the back. Skin irritation or raised bumps will develop if allergies are present. When skin tests can't be used, a blood test called a “RAST test” is used to look for IgE antibodies which show that the body is primed for a reaction.

If no allergies are present, but intolerance is suspected, an elimination diet may be used to determine the source of illness and discomfort. The diet begins with a limited variety of foods that are unlikely to cause a reaction. Gradually other foods are added over a period of days or weeks and symptoms monitored to determine the offending food. The most common sources of intolerance are wheat gluten and lactose from dairy.

Food Allergy Symptoms

Food allergy symptoms vary from person to person and may be mild to severe. They can start within minutes of consumption or several hours later.

Symptoms may include itching or tingling in the mouth, difficulty swallowing or breathing. Gastrointestinal symptoms like nausea, vomiting, abdominal pain and diarrhea may develop. These symptoms are often the same with food intolerance. Other symptoms can include skin rashes like hives or eczema. Food allergies may also trigger asthma. Anaphylaxis, a sudden drop in blood pressure accompanied by swelling and difficulty breathing, is a rare but potentially fatal symptom if not treated immediately.

Help for Food Allergies

It is highly recommended that those with food allergies completely avoid the trigger food. Antihistamines, either over the counter or prescription, are often used to treat those with mild food allergies. Those with potentially life-threatening allergies should keep a kit with epinephrine on hand to prevent anaphylaxis in case of accidental exposure.

Those with food intolerances should also avoid troublesome foods, however there are often natural enzymes and other substances that can aid in digestion and ease troublesome gastrointestinal symptoms.