What is Food Allergy?
A true food allergy, or hypersensitivity, is an abnormal response to a food, triggered by the immune system and involving the production of IgE antibodies.
Food allergies are far less common than most people think. Researchers in Amersham, England, surveyed 7,500 households and found that one in five persons—20 percent of the group— believed they had food allergies. When tested, however, fewer than 5 percent showed real sensitivities.
In the United States, 25 percent of people believe they're allergic to one or more foods, but experts put the true figure at 6 to 8 percent of children up to age three, and about 2 percent of adults. Other reactions, they say, are probably food poisoning, food intolerances, or bad eating habits.
After age three, children usually outgrow their food sensitivities, except for shrimp, peanut, and tree-nut allergies, which tend to be more severe. Most adult allergies disappear after one to two years of complete avoidance of the offending food.
If you're a parent, be aware that your babies have a good chance of inheriting food allergies—not necessarily yours, but allergies all their own. Much depends on timing, and how long you wait before exposing your child to potentially allergenic foods. Some pediatricians suggest withholding peanuts and all nut products—the most common serious offenders—until the child is at least three years old. (Yet surprisingly, a recent British study showed that babies of mothers who ate peanuts while pregnant or breast-feeding did not usually develop peanut allergy.)
For adults and children with food allergies, avoidance is the only way to go—both the prevention and the cure. Assuming you know what to avoid, read labels religiously, and take great care when preparing food. A spatula used to flip an omelet, then used on fried chicken, for instance, could spark a reaction in an egg-sensitive child.
Some adults take the precaution of calling restaurants several hours before they plan to attend, and informing them of their (or their children's) allergies. One woman even has cards printed with her allergies carefully spelled out. She goes so far as to ask that no one in the kitchen wear latex gloves when preparing her food, then hands the cards to her waiters before ordering. When they see her printed instructions, they may groan, but they take her seriously. (No one wants a lawsuit.)
Almost anyone can develop a food allergy if some or all of these factors are present:
• An inherited tendency to allergy
• Sufficient time and/or exposure
• A potent allergen (Prime suspects are milk, eggs, wheat, peanuts—a legume, not a nut—fruits, corn, soy, nuts, and seafood.)
• A run-down physical condition or illness
• Stress or emotional trauma
• Use of mucosal irritants such as aspirin, arthritis medications, or alcohol, which can change the surface of the intestines, allowing more allergens to be absorbed into the system
HOW TO RECOGNIZE A FOOD ALLERGY
A true food allergy, involving the immune system, differs from a food intolerance—an adverse food reaction that doesn't have an immunologic basis. Differentiating is important in that failing to identify a food allergy may leave you unprepared for a crisis. But how do you tell which is which?
Sometimes it's almost impossible. Ask yourself the following questions:
1. Are you allergic to other substances? (If yes, you're more likely to be food-reactive.)
2. Do your reactions occur relatively soon after eating a certain food? (A few minutes to two hours for most allergies, two to six hours for most intolerances.)
3. Do your mouth and throat itch after eating a certain food?
(This usually means allergy. If you're sensitive to ragweed, be wary of cantaloupe, honeydew, watermelon, sunflower seeds, cucumbers, and bananas. Some people who experience hives, itching, or wheezing after eating bananas, cherries, water chestnuts, or avocados are also sensitive to condoms, balloons, and latex gloves.)
4. Does your nose run after eating a certain food? (Unless it's hot soup or hot pepper, suspect allergy.)
5. Does your skin break out after eating a certain food? (Skin rashes are a common food-allergy symptom.)
6. Do you have abdominal discomfort after eating a certain food? (No clues here. Gastrointestinal upsets such as cramps or diarrhea are common to both allergies and intolerances. When the symptoms are accompanied by a skin rash or a runny nose, however, allergy becomes more likely.)
7. Did others who ate the same food as you did at a particular meal get ill? (If so, the problem may be contamination. Suspect spoiled, unclean, or undercooked fish, meat, poultry, dairy, or egg products.)
8. Do certain foods make you feel sad or depressed? (The jury's still debating. Many believe food allergies directly affect emotions. Others disagree.)
9. Do you ever have a problem with narcolepsy, i.e., falling asleep, uncontrollably, at strange times? This symptom has been related to both food and inhalant allergies.
Your answers to the preceding questions may give you clues but not conclusions. In order to better determine what is a food allergy, you need to know what isn't. |
