By Martha A. Simpson, D.O., M.B.A.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

MOST FOOD ALLERGIES ARE MERE NUISANCE, SOME ARE LIFE-THREATENING

Question: I think I have food allergies. Someone has suggested that I get ALCAT testing. How do I find out if I am allergic to certain foods?

Answer: True food allergies are less common than most people think -- affecting about 8 percent of children and 2 percent of adults. Symptoms typically appear quickly after the person has eaten the food to which he or she is allergic. This time period can range from minutes up to about two hours. While most food allergies are a mere nuisance, a few folks will experience a serious generalized reaction called anaphylaxis.

The most common symptom of a food allergy is hives. These red, itchy patches appear suddenly and usually disappear within a few hours. Another frequent reaction triggered by food allergy is atopic dermatitis, also called eczema. This condition is characterized by scaly, red skin that itches. Also, runny nose, watery eyes and facial swelling are common.

More serious symptoms that can be a sign of anaphylaxis, include a tingling sensation in the mouth, flushing, swelling of the tongue and the throat and a feeling of light-headedness. This can progress to swelling in the airway, difficulty breathing, vomiting, abdominal cramps, diarrhea and a drop in blood pressure. Without prompt treatment, anaphylaxis can lead to collapse, loss of consciousness and death.

While almost any food can cause an allergic reaction, a few foods are common offenders. In children we see allergies to cow’s milk, egg whites, wheat and soy. Life-threatening anaphylaxis is most frequent with peanuts, tree nuts, fish, shellfish and seeds, such as sesame and caraway.

The best way to begin diagnosing food allergies is to keep careful records of what you have eaten and what reactions occur. Allergic symptoms that appear right after eating can be the first clue to a food allergy. Once you notice, for example, that every time you eat a certain food you get hives, you should eliminate that food from your diet.

Another way to self test for food allergies is to stop a suspected food for several weeks, then reintroduce it to see if a reaction occurs. You would only want to try this if you had a mild reaction to the food initially.

I recommend that you perform such self tests in consultation with your family physician. He or she can help you interpret your results, recommend additional tests and determine if you need to see allergist.

There are two types of recognized allergy testing -- a skin prick test and the RAST test. They are commonly used to begin to determine if an allergy exists. Both are usually accurate, but neither is totally reliable for food allergy testing. There are many other tests around, such as the ALCAT that you mention, but these are not recommended by mainstream medicine as they have not been proven to be scientifically reliable.

Mild food allergies such as those seen in childhood often go away within a year or so. Severe allergies that cause anaphylaxis are lifelong, and the offending foods should be avoided forever.

Finally, remember that if you have severe symptoms that you believe are due to an allergic reaction, it’s a medical emergency. You should seek immediate medical help.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701, or via e-mail to readerquestions@familymedicinenews.org. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnose and recommend treatment for any medical conditions. Past columns are available online at www.familymedicinenews.org.