A food allergy is a reaction to a protein found in a specific food. Allergic reactions take different forms. Most common are: Systemic: Anaphylaxis is an immediate and severe allergic response that involves two or more systems. Symptoms can include shortness of breath, wheezing, hives, swelling (of the lips and face), vomiting, lowered blood pressure and dizziness. Anaphylaxis can progress to anaphylactic shock, a potential life-threatening condition.
Digestive: Includes vomiting, abdominal pain, diarrhea, malabsorption of nutrients. Respiratory: May include runny nose, nasal congestion, difficulty breathing, wheezing.
Skin: Includes rash, hives, eczema.
In North America, an estimated three to four percent of children and one to two percent of adults have food allergies. Fortunately, many children outgrow allergies.
How do I know if my child has a food allergy? It’s very important to work with an allergist and/or physician for a proper diagnosis. Keep a food diary of everything your child has eaten for one to two weeks, his symptoms and how long after eating the symptoms occur. With this information, allergy testing and a physical examination, your allergist/physician can help determine which food is causing the reaction. In working towards removing the allergenic foods from the diet, talk to a dietitian who can help ensure food choices stay balanced and meet nutrient needs.
What foods are the most common causes of food allergies? Although any number of foods can cause allergic reactions, some are more common than others. In Canada, common food allergens include: milk, soy, eggs, peanuts, tree nuts (almonds, pecans, walnuts and other nuts), seafood, sesame seeds, wheat and sulfites (more a sensitivity than an allergy).
What should I watch for with a milk allergy? Cow’s milk allergy occurs in about two or three of every 100 infants—although most outgrow it by the time they’re three. Infants at higher risk of developing milk allergy include those where one parent, or both (or a sibling) had milk allergy as an infant. Symptoms include vomiting, diarrhea and poor weight gain. Skin or chest symptoms or blood in the stools may also occur.
Milk ingredients are not always clearly identified on food labels. Any of the following words on a label indicate milk protein. – milk – condensed milk – evaporated milk – milk powder – butter – milk solids – cheese – cottage cheese – sour cream – yogurt – buttermilk – curd – cream – cream cheese – quark – ice cream – sherbet – feta/ricotta – casein – sodium caseinate – potassium caseinate – whey – lactoglobulin – lactose
Helpful products for milk allergy: Rice milk/beverage is a common substitute for cow’s milk. It doesn’t contain the same nutrients as cow’s milk so calcium and vitamin D supplements are often needed. Fortified soy beverage is a good substitute for cow’s milk as it provides the same amount of protein and other nutrients such as calcium and vitamin D. However, many people who are allergic to cow’s milk are, unfortunately, also allergic to soy protein. It is advised to try soy beverage under the supervision of a physician. The same is true with goat’s milk. There are hypo-allergenic infant formulas available if bottle-feeding. Other dairy-free foods include non-dairy chocolate (carob), cheese, yogurt and non-dairy ice cream.
What should I watch for with an egg allergy? Common in young children, delaying the introduction of egg yolks until an infant is at least six months old is important. Egg whites should not be introduced until at least one year of age. Avoiding a whole egg is fairly easy. Because eggs are so widely used as an ingredient, it is often much harder to avoid foods that contain eggs. Common egg-containing foods include custards, egg nog, Caesar salad dressing, cakes, cookies, pies, pancakes, waffles and battered foods. Eggs may also be used as a clarifier in consommé and some soft drinks (like root beer). Egg beaters®, while sold as an egg substitute, are not egg-free. Some vaccinations also include egg protein. Your doctor will be able to give you information if you are concerned about egg allergy and vaccines.
If you see any of the following words on a food label, it contains egg protein: – albumin – egg – baking powder – ovalbumin – egg white – ovomucin – egg yolk – ovovitellin – globulin – livetin – mayonnaise – egg powder – ovoglobulin – egg protein – ovomucoid – frozen egg – pasteurized egg – simplese – vitellin
Helpful products for egg allergy: While there are no alternatives to replace the taste of eggs, there are some substitutes that can duplicate their cooking qualities. Many egg-free recipes use a mixture of vegetable oil, baking powder and water for the egg. With egg substitutes, be sure to check the label carefully, as some still contain egg whites. Medium-firm tofu can be tried as a substitute for scambled eggs.
How can I manage a peanut allergy? Unlike milk and egg allergies, peanut allergies generally persist beyond childhood. This type of allergy is common, one of the most severe and often the cause of anaphylactic shock. While a peanut allergy does not necessarily extend to all nuts, anyone who has had a previous anaphylactic reaction to peanuts should avoid all nuts to be safe. Pure peanut oil should also be avoided, since, although theoretically free of peanut proteins, it may contain trace amounts. Peanut oil is widely used in many restaurants (e.g. Thai and Chinese), so you may choose to avoid these places altogether. Be sure to read labels for foods that ‘may contain’ peanuts and avoid these. Fortunately, a growing number of peanut-free products are available that provide more options for families dealing with nut allergies. Some great examples include: No Nuts Pea Butter, Quaker Peanut-Free Granola Bars and for occasional treats Nestle Snack Size Chocolate Bars and Mars Chocolate Bars.
What foods should I watch out for with a wheat allergy? While not common, grain allergies do occur, with wheat as the most likely cause. This allergy is an adverse reaction to the protein component of wheat. It is different than celiac disease (increasingly common) in which affected people cannot tolerate gluten (a protein found in many grains including wheat, oats, rye and barley). Celiac disease also requires significant lifelong dietary changes, beyond eliminating wheat from the diet.
Wheat is found in many foods, including breads, cereals, pastas, cakes, luncheon meats and sausage—virtually anything that contains wheat flour. Because wheat flour is often fortified with vitamins such as riboflavin, thiamin, niacin and iron, the elimination of wheat from the diet can result in a nutrient deficiency unless replaced with other foods, including alternate flours such as rye, corn, or rice.
By Patricia Chuey, Msc, RDN
Where can I find more resources and information on allergies? www.aaia.ca (Allergy/Asthma Information Association) www.foodallergy.org (Food Allergy and Anaphylaxis Network) www.peanutallergy.com, www.abcpeanut.com, www.glutenfreediet.ca, www.celiac.ca
Some of the information used in this article has been reprinted with permission from Better Baby Food, by Daina Kalnins and Joanne Saab, Robert Rose Inc. 2001. An excellent resource.