Food allergies are becoming more frequent as a consequence of many factors. It is well known by the general public that countless people in  the United States are afflicted with seasonal inhalant allergies to pollens, trees, molds, animal danders, and feathers. The newsprint media and television ads for numerous over the counter and prescription medications for treatment of these allergic triggers are viewed repeatedly each day.  The misery index of those people afflicted with inhalant allergies varies subjectively from mild to very severe. Fortunately, although the misery index is high, the morbidity and mortality incidence is low. Patients with severe pulmonary conditions like unstable severe asthma or chronic obstructive pulmonary disease (COPD) are at increased risk for complications associated with inhalant allergy attacks. The vast majority of inhalant allergy sufferers, however, are plagued with non life - threatening bothersome nasal congestion, itchy or watery eyes, runny nose, sinus congestion, postnasal drainage, sore throat, headache, fatigue, insomnia, and other symptoms that affect their quality of life.

Food allergy, however, has potential to be far more serious than inhalant allergy depending on the type of food allergy present. The danger of food allergy has only recently been presented to the general public due to increased incidence of serious and fatal reactions. The most common foods associated with allergy reactions differ based on age groups. Children are more frequently allergic to milk, eggs, soy, and nuts; adults to peanuts, tree nuts, shellfish, milk, and eggs. The chance of developing a food allergy is greater in people whose parents both have an allergy to inhalants or foods. It is currently estimated that about 4-5% of people in the United States have true food allergy. An even smaller percentage of these are at risk for a life threatening food allergy or anaphylaxis attack. Food allergy accounts for an estimated 200,000 emergency room visits per year in the United States.

 
There are two major classes of food allergies: Fixed and Cyclical.

Fixed Food Allergies:
Of the two types of food allergies, fixed food allergies are more dangerous as they are the type most commonly linked to anaphylaxis, a life-threatening allergic reaction. An estimated 3,000 people die each year in the United States from delayed or inadequate treatment for this condition. Food allergy, insect bites or stings, and allergic pulmonary reactions are the main causes of this alarming number of deaths. Anaphylaxis requires prompt and aggressive treatment to reduce the swelling (angioedema) that occurs within the mucus membranes that line the entire aerodigestive tract. Rapid drop in blood pressure and hypovolemic shock combines with the angioedema to produce a total body response that can, if untreated , rapidly cause death.

Fixed food allergy reactions are almost always rapid (immediate -15 minutes) in onset after exposure to the allergic food. The exposure can result from absorption with skin contact, inhalation, or ingestion of even small amounts of the fixed food allergen. The importance of recognizing and avoiding all the above entry exposures was recently widely reported by the media. The tragic case of a young teenage student, with a severe fixed peanut allergy, who died soon after receiving a passionate kiss from his girlfriend, who had just eaten a peanut butter and jelly sandwich, showed the danger of severe fixed food allergy.
The safest test to document a fixed food allergy is a blood test (RAST) that identifies a true IgE Type I allergic immune response. This test technique does not expose the person to the risk of anaphylaxis present with skin testing or oral food challenge testing. The (+) RAST test combined with a confirmatory history of exposure to that food or substance is diagnostic. People who are found to have a fixed Type I (IgE) allergy to any food, additive, dye, or chemical element are advised to totally avoid that substance in any quantity to prevent the chance of anaphylaxis. 

Cyclical Food Allergies:
Cyclical food allergy is fortunately much more common than fixed food allergy. This type of reaction, like a fixed food allergy, is based on prior exposure and sensitization to the respective food or substance. A symptomatic cyclical food allergic reaction is based upon the frequency or quantity of contact with the allergic food or compound. This explains why a person allergic to corn can eat the vegetable every 4-5 days without any adverse effects; eating corn two days in a row or eating 12 ears of corn at a single meal, however, can trigger an allergy attack.
Food allergies do not always present with symptoms that one would expect. A food allergy can present with the same symptoms as inhalant allergies: clear nasal drainage or congestion, itchy throat or roof of the mouth, sneezing, etc. An allergic reaction to a cyclical food allergen does not have to present with any GI related symptoms like excess cramping or gas, indigestion, heartburn, belching, nausea, or diarrhea. Many people and some physicians will miss recognizing a cyclical food allergy because of the complement of symptoms unrelated to the digestive system.

The best test to document a cyclical food allergy is the oral food challenge (OCT).  A double blinded study is time consumming and more expensive and the patient can do this in a related form at home PROVIDED  that no severe reaction has ever occured with the suspect food.The person is asked to avoid the suspected allergic food for 4 - 6 weeks. They then try, in pure form (no added ingredients and preferably raw or poached),a small portion of the suspect food. If no adverse reaction is noted, they perform another oral challenge the next day, if still no reaction, they take a second challenge that same day several hours later. If still no response that food should be safe to consume every 4 days without expected adverse allergy response. 

Food Allergy or Intolerance:
To add to the confusion of accurately diagnosing a food allergy is the food "intolerance", "oral allergy syndrome", exercise induced food allergy, lactase deficiency, gluten intolerance, and chemical (yellow dye #5) or additive (MSG) reactions or diagnoses. All these conditions can cause symptoms that closely resemble a true food allergy but are NOT an allergic reaction. An exception may be "oral allergy syndrome" which is a cross reaction between an inhalant allergy and ingestion of a certain food: ragweed and melons (especially cantaloupe) or birch tree pollen and apple peels/skins.  The other reactions mentioned cause many allergic type symptoms like gastrointestinal symptoms ( cramps, bloating, pain, diarrhea), dizziness, headaches, and fatigue. These conditions are discussed more thoroughly in the reference link provided below. 

Food Allergy Treatment:
We currently use a dietary food intake list of all food consumed weekly and intermittently, an accurate symptom history, and specific blood tests to diagnose a food allergy. All patients identified with cyclical or fixed food allergy are then counseled by Dr. Sciacca after evaluation of all data and test results. A rotational diet is recommended for all our cyclical food allergy patients. Other appropriate allergy and stomach symptom relieving medications are prescribed on an individual basis. Dr. Sciacca has affiliated area registered dieticians(R.D.'s) with food allergy experience to whom he refers his severe or fixed food allergy patients. These professionals provide our food allergy patients with additional education regarding substitute foods and related food family groups that may be closely related to their food allergy(s). If you suspect a food allergy please feel free to call our office for an appointment.  

For more information about food allergies

4501 Southlake Pkwy
Suite #200
Hoover, AL 35244